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Data collected by Magann et al. (1996, 2002) on employment, exertion and outcome in Australian women suggest that women who were least active, in either employment or other physical activity, were at most risk of pre-birth admission to hospital and of PTD, and another study points to the benets of non-sedentary employment, together with leisure time physical activity, particularly in reducing risk of pre-eclampsia (Saftlas et al., 2004) (see also Chapter 5). Once again, the message in terms of 70 women's ability to respond appropriately in relation to their work practices is difcult to interpret. Clearly, some women are at risk, with those in the highest exposure category at risk of giving birth prematurely. The highest risk category means that they would have prolonged standing, considerable physical exertion and long working weeks. In these cases, women might be advised that continuing in employment might be putting themselves and their baby at risk.
A major consequence of research into outcomes has been the development and content of advice for pregnant women, at work and elsewhere, on activities to pursue, maintain or avoid. We address this topic at some length in Chapter 6 on exercise but in the context of this chapter on pregnancy and employment we open the discussion here by examining how prevailing discourses of responsibility present in research are translated into practice through advice.
Enacting responsibility: responding to advice The nature of advice provided is that women should avoid or maintain certain behaviours in relation to paid work, with standard advice to take more rest, to sit down regularly, to avoid heavy lifting and bending and to avoid working with chemicals, lead or x-rays. The prevailing biomedical discourse of pregnancy serves to locate advice as authoritative and rea.s.suring. However, advice about working is often contradictory or ambiguous, and though it stops short of dictating how women behave, it is often hectoring or patronising in style. As might be expected in the light of the extensive literature on the links between employment, aspects of job tasks and adverse pregnancy outcome, the advice is centred on the avoidance of risk and makes use of the literature we have discussed above. This has the effect of positioning work as one of the elemental forces' (Smith, 1992).
Paid work is presented as potentially dangerous for the baby and, in order to minimise the danger, the expectation is that women will manage to accommodate their need to work and simultaneously to extricate themselves from its risky components. Of course, this discourse of riskiness is also available to others in the workplace who may be able to use it to their advantage by pressuring women to behave in ways that might appear concordant with their own expectations but are in fact disadvantageous.
Representations of advice, however, fail to make connections between the discrete elements of research evidence that have emerged, for example that women may suffer stress at work, which is risky for the baby, but that it is others who are responsible for creating the stress, not the women themselves. Emphasis throughout is on how the woman can adjust her lifestyle and behaviour to reduce exposure to stress or other conditions that might be harmful.
71.The contradictory coverage of the risks a.s.sociated with working incidentally acts to separate public and private activity. As we have highlighted above, discussion of paid work rarely transfers into the private domain and domestic work in the home is largely ignored, with some exceptions.
Features on the demands of working and being responsible for home life are addressed occasionally, and indicate that women should avoid the double demands, though how this might be done is less well dened.
Specically, advice requires women to be proactive on their own behalf and that of their baby. As we have seen from the studies of women's experience at work, this is not always easily accomplished because of considerable opposition to providing exibility or even of conforming and responding to policy requirements. The difculty some women encounter is addressed in ways that make it sound as though it is merely a matter of being clear about needs and calling on legislation for back-up. As the various EOC surveys have shown, this is hardly helpful in many situations where pressure from others is signicantly greater than an individual might be in a position to confront.
A fascinating way in which women may respond to the demands to be proactive and to avoid risk is exemplied in our prospective study of women's changes in activity over the course of pregnancy (Clarke and Gross, 2004a; Clarke et al., 2005; Rousham et al., 2006). In this study, whose other ndings are discussed again in Chapter 6 on exercise activity, women's daily activity was measured through the use of activity monitors and through self-report. The ndings indicate that overall activity levels declined across the course of pregnancy. When this was broken down into the differing realms of activity, a similar pattern was demonstrated with mean self-reported total occupational activity levels decreasing over time.
Even prior to maternity leave, the mean number of hours worked per week decreased signicantly between 16 and 34 weeks of pregnancy. The women in our study were fortunate enough not to experience discrimination, and were generally treated well by their employers. Though, of course, as others have indicated, those who felt they might encounter difculty may have left work earlier, making the group of women involved in the study in some ways atypical in this regard. Most of the women reported that they had made adaptations to their work, nevertheless.
Most interestingly, given the advice to rest as much as possible but also to maintain activity, women undertook a neat s.h.i.+ft in their activity, whereby a signicant decrease in the mean total length of work breaks was observed, but the frequency of work breaks increased. In response to restrictions on the time available for breaks something women often reported the women managed their time differently in order to conform to the need to take more or at least adequate rest. The physical aspects of work, including working posture or stairs climbed, did not change signicantly (though most women's jobs were largely sedentary) since these 72 were mostly xed components. What women did report was that they changed the behaviour that was under their control, even if the activities did not form part of the women's daily routine, such as reducing lifting and carrying or bending: 89 per cent of the women reported not lifting although only 27 per cent had originally indicated that their job required them to lift heavy loads. However, this involved a subtle combination of behaviours in an attempt to minimise the impact on their role in paid employment and to undertake appropriate responses to the risks to maternal and foetal wellbeing. The adaptations were unlikely to impinge on productivity or performance and were under the women's individual control. This included the number of trips made around the ofce environment, recruiting others to do small tasks for them, such as taking things to other ofces when they are pa.s.sing and taking paper to the photocopier.
Such subtle changes may be a reection of how pregnancy may legitimate opportunities to relinquish roles or responsibilities that are considered irksome, boring or unnecessary. Alternatively, they may be represented as a woman's engagement with the perceived responsibilities of motherhood. The decision to maintain workplace activities, on the one hand, yet change the more exible elements of their job, on the other, may reect cultural att.i.tudes too. As other studies describing women's experiences at work have demonstrated, women have to conform to the role of responsible mother and as an individual with agency. By announcing that they have changed behaviour they are conforming to the explicit demands to minimise risks. At the same time they are maintaining agency through their judgement of the potential impact of their changes on their working day.
Concluding remarks In general terms, we can conclude from the available research that for most pregnant women work is not a source of serious problems, either in psychological terms or in terms of pregnancy outcome. Nevertheless, for some women, notably those in positions with less control and poorer working conditions or in smaller workplaces, the experience may not be as positive. As the case of pregnancy discrimination in the workplace demonstrates, pregnancy retains a potency that is perhaps unexpected in the early twenty-rst century. The issues raised by the negative treatment described appear to revisit a continuing ambiguity in societal or public beliefs about the divisions of labour and essential roles and about women and femininity.
These are very fundamental beliefs that cannot easily be dismissed by the presence of policies and laws designed to prevent their impact. Moreover, the protective framing of pregnancy legislation, together with the research striving to isolate the precise sources of harm, positions women and their babies as at the mercy of risks arising in the public world of work. The 73 treatment of women in the workplace is simultaneously accounting for and making women accountable to those risks. The construction of pregnancy as a risky endeavour emphasises the metaphors of containment which are inherent in the discussions that follow concerning diet and exercise.
The willingness of individuals to offer up their relinquis.h.i.+ng of activities identied as appropriate in the advice they receive suggests to us that it is possible to manage the demands created by the conicting and confusing evidence in a personally meaningful way. It is possible that where treatment at work is less positive, this controlled adjustment and accountability is more difcult to accomplish and, paradoxically, in being attempted may even reinforce att.i.tudes and beliefs about pregnancy in colleagues and employers. The pregnant woman in the workplace could be said, therefore, to provide a focus for all these beliefs that at other times remain unchallenged.
5.EATING FOR ONE OR EATING FOR TWO.
Diet and eating behaviour in pregnancy.
Changes in diet and eating behaviour are an essential part of the stereotypical image of pregnancy, but surprisingly little research has concentrated on what women actually eat and why. Pregnant women are typically depicted as being plagued by strange and irresistible cravings as well as having aversions to certain foods. Nausea, familiarly, though inaccurately, known as 'morning sickness', is seen to be characteristic of pregnancy and in popular culture is regularly depicted as the earliest somatic symptom.
The regularity of the reporting of somatic symptoms across the world suggests that these symptoms and dietary change in pregnancy are driven by physiological and endocrinal factors. Certainly research in this area routinely a.s.sumes that these are the only drivers but it is likely that other, psychological factors may be as important. In the case of eating behaviour, a combination of dietary beliefs, an a.s.sociation of symptoms with diet in the past, and past dietary behaviour may be used to guide behaviour and interpret experience. There are many traditional beliefs about what and how women should and should not eat during pregnancy, some of which appear to be common across cultures, for example that women should increase their food intake at least in the early stages, as summarised in the phrase eating for two'. Other dietary beliefs seem to be very culturally specic and derive from belief systems relating to the body and the development of the foetus, for example pica the craving for and eating of non-food substances such as earth and clay, as Walker et al. (1997) investigated in South Africa.
Although the adoption of stereotypical beliefs may limit women's choices, it also sanctions behaviour that is otherwise not regarded as acceptable in young women, for example satisfying 'cravings' allows high calorie eating patterns. Many young women restrict their caloric intake in pursuit of the current ideal feminine body shape in the developed world and concern is often expressed in the popular press in the developed world about children and young girls as young as seven years old restricting their food intake. It has been estimated that on any given day approximately 45 per cent of American women are on a diet. Eating disorders, princ.i.p.ally anorexia and bulimia nervosa, are largely afictions of women (Andersen, 75 1995) and women of all ages express dissatisfaction with their body (Stevens and Tiggemann, 1998). Estimates of the prevalence of eating disorders in women of childbearing age have been found to be between 1 and 2 per cent (Fairburn and Beglin, 1990).
Further pressures on pregnant women come from external sources. As we have shown in Chapter 4, and as David-Floyd (1994) points out, the pregnant body can be seen as inappropriate. In Chapter 7, we see how pregnant celebrities are currently usually depicted in the media as remaining slim during pregnancy and rapidly regaining their pre-pregnancy shape.
Therefore, for many women, pregnancy, with its accompanying change in body size and shape, may be seen as a personal challenge.
To add to these pressures, pregnant women are often the target of food scares in the media. In some instances this is because a link has been posited, by epidemiologists or basic scientists, between particular foodstuffs and foetal wellbeing (for example, there were reports in 2002 on the possible risks of drinking too much coffee and the dangers of mercury in tuna sh). In other cases, targeting arises because pregnant women are generally regarded as a vulnerable group, alongside older people and the very young. So if a foodstuff is discovered, or thought, to pose some health risk, then vulnerable groups are advised to avoid it. This was the case in the UK when there were reports on the risks of Salmonella in chicken eggs, which originally appeared in the 1980s and reoccurred in the late 1990s.
How women respond to these scares is less frequently reported.
And it is not just the potential risk of poor foetal outcome; the diet of women during pregnancy has a signicant impact on their long-term health. The most rapid rise in obesity and overweight in women occurs during the peak childbearing years (Department of Health, 2002) and obesity is a major factor in ante- and perinatal maternal deaths (Lewis and Drife, 2004). Importantly, for long-term health, 1420 per cent of women are 5kg or more heavier 618 months post partum, compared to their pre-pregnancy weight (Keppel and Taffel, 1993; Ohlin and Rossner, 1990). As has been regularly doc.u.mented, obesity and overweight are increasingly important health problems and are a.s.sociated with a number of diseases including hypertension, type II diabetes, cardiovascular disease and some types of cancer (NIH, 1998).
Despite the known impact of diet on the health of women, it has taken the results of long-term studies of its impact on the health of offspring into adulthood to prompt the interest of mainstream medical researchers in maternal nutrition during pregnancy, outside underdeveloped countries where even basic nutrition is problematic. Poor maternal nutrition has long been linked to foetal and child ill-health. This effect is due not only to insufcient energy intake overall but also to the incorrect balance of food types and nutrients, leading to restricted intrauterine growth, low birthweight, prematurity and other perinatal morbidity (Kramer, 1993). More 76 recent research suggests that several diseases of later life also originate from impaired intrauterine growth and development, leading to permanent effects on structure, physiology and metabolism (G.o.dfrey and Barker, 2000; Mathews et al., 1999). This is known as thefoetal origins' or Barker hypothesis, named after David Barker who studied the records of 16,000 men and women born in Hertfords.h.i.+re, England from 1911 to 1930 and whose records can be traced to the present day. The birth records on which these studies were based came to light as a result of the Medical Research Council's systematic search of the archives and records ofces of Britain.
The Hertfords.h.i.+re records were maintained by health visitors and include measurements of growth in infancy as well as birthweight. Death rates from coronary heart disease fell two-fold between those at the lower and upper ends of the birthweight distribution. Barker concluded: 'The fetal origins hypothesis states that fetal under nutrition in middle to late gestation, which leads to disproportionate fetal growth, programmes later coronary heart disease' (Barker, 1995: 171). Similar results have been reported in other European countries, India and the US. More recently, excessive maternal weight gain has also been related to perinatal problems in babies (Kabiru and Raynor, 2004) and to childhood obesity (Whitaker, 2004). Higher levels of obesity and of infant mortality and morbidity (a.s.sociated with poor maternal nutrition) are seen in more disadvantaged groups in the UK (Department of Health, 2002; Macfarlane et al., 2000). This work prompted an ongoing large-scale survey of the lifestyle and dietary behaviour of 20- to 34-year-old women in Southampton in southern England.
Three thousand of the 12,500 women surveyed became pregnant during the course of the study, and their dietary behaviour is being closely monitored.
Such surveys and monitoring research will add considerably to our knowledge of what women eat during pregnancy and how their diet changes. However, we still know little about what prompts women to change their diets during pregnancy and what external pressures, personal beliefs and habits underlie the dietary choices they make: for example, whether women who eat healthily prior to pregnancy make more changes than those who do not. In this chapter we consider the research on various aspects of dietary behaviour during pregnancy and reect on research perspectives. On the one hand these perspectives take pregnancy out of the context of women's lives and, except in the extreme case of eating disorders, disregard previous eating behaviours. On the other hand they fail to take account of the inuence of women's culturally embedded beliefs about pregnancy as a different and specic physical experience.
Dietary beliefs and dietary change There seems to be general agreement among those with expertise in nutrition and women themselves that diet should change during pregnancy.
77.At the very least, the extra demands on the body call for increased calorie consumption of about an extra 200 calories a day. Beyond this consensus, however, there seems to be wide variation about what exactly is an appropriate diet during pregnancy, with competing information from the media, health professionals and pregnancy manuals and from family and friends. Beliefs about changing one's diet during pregnancy may be a.s.sociated with the wellbeing of the mother, with the wellbeing of the baby or with a desirable weight gain. Such beliefs may be rooted in the woman's own past eating behaviour, in antenatal health education or may have been transmitted from generation to generation within a particular culture or subculture.
One of the rst questions we should ask is whether women do deliberately change their diet during pregnancy for either their own or their child's wellbeing. The answer, from our own and others' work, suggests that they do, and that the changes seem rather more motivated by concern for their child than themselves.
Two early studies of US women looked at how they reported changing their diet (Norman and Adams, 1970; Orr and Simmons, 1979). In Norman and Adams' (1970) study, approximately two-thirds of the women reported adjusting their diet. Such adjustments included adding, reducing or eliminating foods. Greater intakes of dairy products together with fruit and vegetables have generally been reported as usual dietary additions.
High sugar foods such as desserts, chocolates and biscuits were the items most commonly reported to be reduced or eliminated, as were foods with a high salt or fat content. Orr and Simmons (1979) found that most of the women they studied believed diet to be important for both mother and baby, though a substantial number did not recognise its importance for mothers. However, they did report that they were prompted to change their diet on the basis of advice from health professionals, who may have placed more explicit emphasis on change.
Most studies rely on women's reports of how they change their diets rather than measuring actual food intake. In a study we carried out we examined the eating patterns of a demographically mixed sample of 102 women during their rst or second pregnancy by exploring specic changes that they made to their diet, as well as how somatic symptoms a.s.sociated with pregnancy, such as nausea, affect food choice, and how dietary beliefs inuenced women's food choice (Pattison and Bhagrath, 2003, 2004). We found that 79 per cent of women reported that they should increase consumption of certain foods and 82 per cent reported trying to avoid certain foods. The foods increased were fruit, vegetables and dairy products whereas the foods avoided were foods high in sugar and fat and those that health professionals and other advisors had suggested were dangerous, such as soft cheeses. However, when we measured the actual frequency of consumption, no signicant difference was found between when women 78 last consumed the food they felt they should increase or avoid and their current reported intake, suggesting that other factors are at play.
In a study in the US, Pope et al. (1997) studied dietary changes in pregnant adolescents. Their results indicated that the pregnant girls' diets were more nutrient dense than a matched sample of non-pregnant girls.
Since becoming pregnant, a majority reported that they had increased the amount of food eaten, specically milk/dairy products, vegetables, fresh fruit/unsweetened juices, breads/cereals and chocolate. Health professionals' inuence was cited for increased intake of vitamin supplements and milk, but not for changes in food intake. The major motivations for increasing food intake during pregnancy seemed to be food cravings, increased appet.i.te, improved taste of food and concern for the baby.
So there is evidence that women report changing their diets in such a way as to increase their caloric intake, and specically increasing certain foodstuffs and reducing intake of others. However, what they actually eat is not simply motivated by dietary advice from midwives or nutritionists. One interpretation of our own ndings is that the women in our sample knew what foods their midwives would recommend them to eat, but that somatic symptoms such as nausea, or other beliefs about diet, affected their food choices as well as presumably personal preferences. Traditional beliefs may signicantly inuence dietary patterns and many are not consistent with recommended guidelines for nutrition during pregnancy. Examples of these include eating for two, not mixing certain foods, taking vitamins to overcome an inadequate diet and eating only a few selected foods.
The impact these traditional beliefs have on dietary behaviour in developed countries may be limited because of increasing access to resources, for example formal education, the internet and pregnancy magazines as well as positive media attention promoting healthy eating and regular contact with health professionals, which would subsequently encourage a different att.i.tude towards diet to be established. In our own work in a UK population, belief in traditional eating patterns varied with educational level so that more highly educated women were less likely to endorse such beliefs and less likely to report suffering cravings (Pattison and Bhagrath, 2003).
However, in this sample educational level was confounded with socioeconomic status, as it is in many studies.
In a sample of 6,125 non-pregnant women from the Southampton study, mentioned above, Robinson et al. (2004) examined the inuence of socio-demographic and anthropometric factors on the quality of the diets of young women in the UK. They found that educational attainment was the most important factor related to the quality of the diet consumed. In all, 55 per cent of women with no educational qualications had scores in the lowest quarter of the distribution, compared to only 3 per cent of those who had a degree. Smoking, watching television, lack of strenuous exercise and living with children were also a.s.sociated with lower diet scores. After 79 taking these factors into account, no other factor including social cla.s.s, the deprivation score of the neighbourhood or receipt of benets added more than 1 per cent to the variance in the diet score. The signicance of these ndings is that they suggest that poor diets in general in this group are not simply a result of the level of deprivation, but reect a more general pattern of health behaviour that is linked to poor access to information sources through education.
Some support for this thesis comes from our study (Pattison and Bhagrath, 2004) where women who reported making changes to their diet were also more likely to have made additional changes to their lifestyle.
Although there was no variation on alcohol intake (all women who previously drank alcohol reported cutting down or abstaining from alcohol consumption during pregnancy), more educated and younger women were more likely to have attended antenatal cla.s.ses and changed their exercise levels. In our study, women who increased exercise and women who decreased exercise were cla.s.sied together as having made a change. As we shall show in the next chapter, exercise seems to be an area where pregnant women respond in different ways.
In considering how women respond to pregnancy we should not forget that people's belief systems are complex and they can simultaneously hold beliefs which are conicting and contradictory. A study carried out by Carruth and Skinner (1991) found that a substantial proportion of clients of the 1,771 pract.i.tioners they surveyed had beliefs about physiological needs during pregnancy, practices related to a healthy baby and alcohol and caffeine consumption that were not signicantly different from those endorsed by the American Dietetic a.s.sociation. However, they also held beliefs, particularly about cravings, which showed strong regional differences, and which represent traditional views not supported by dieticians (e.g. eating for two, eating only a few selected foods, restricting salt intake, taking vitamins to overcome an inadequate diet and deciding that pregnancy is a good time to lose weight). This study was performed in the US.
However, few similar studies have been done elsewhere to a.s.sess whether similar beliefs exist and if so to what extent. Nevertheless, as we discuss below, advice given by midwives and in publications for pregnant women is often vague, recommending ahealthy diet' and being open to interpretation within the woman's own belief system. Many traditional beliefs about diet in pregnancy revolve around cravings, aversions and somatic symptoms of pregnancy, particularly nausea and vomiting, and we will now consider these in more detail.
Cravings, aversions and somatic symptoms Many women report cravings and aversions towards particular foods during pregnancy; the reported occurrence in the literature ranges from 66 80.to 85 per cent. Cravings and aversions are undoubtedly at least partially interrelated with beliefs as the behaviour of consuming or avoiding particular foods during pregnancy may be directly related to cultural or social values. For example, there is a strong belief system within certain cultures to support pica, which is the consumption of non-food substances such as clay and earth. Food cravings may also be experienced as a somatic symptom though these are also likely to be inuenced by cultural beliefs (Bayley et al., 2002).
The medical model of pregnancy suggests that all experience of pregnancy is related to physiological and endocrinal change, thus much early research on cravings and aversions a.s.sumed that the root of these desires is a mechanism to protect the foetus. Therefore, cravings are seen as a way of making up for dietary inadequacies and aversions, and nausea and vomiting are seen as a way of protecting the foetus from noxious substances.
Traditional beliefs about food restrictions have also been investigated in this way. Fessler (2002), for example, suggests that maternal immunosuppression, which is necessary for tolerance of the foetus, results in vulnerability to pathogens. Symptoms could be abehavioural prophylaxis'
against infection, with nausea and aversions leading to the avoidance of foods likely to carry pathogens, and cravings leading to foods which boost the immune system. A similar conclusion is reached in a review by Flaxman and Sherman (2000) of morning sickness and pregnancy outcome. This was particularly a.s.sumed in the case of pica, the most extreme and unusual of cravings. These a.s.sumptions are also found in the explanations women themselves give for what they are experiencing. Several studies carried out in the US by Carruth and Skinner on pregnant adolescents identied beliefs which gave aphysiological basis' for cravings. For example should give in to my cravings or I will harm my baby' and 'foods that make me feel sick must be bad for my baby' (Pope et al. 1992).
Several other studies which have looked at the impact of pica on pregnancy outcome appear to refute the dietary deciency theory. In certain societies pica is common. Luoba et al. (2004) found that 378 of the 827 women they studied in western Kenya were eating earth. Horner et al.
(1991), in a review of pica in the US, showed that the prevalence of pica among pregnant women from poor, rural and predominantly black areas declined between the 1950s and the 1970s but then remained constant.
They conclude that the evidence suggests that pica during pregnancy is a.s.sociated with anaemia and with maternal and perinatal mortality. Lopez et al. (2004) found a prevalence of 23 to 44 per cent in Latin America.
Rainville (1998) investigated the a.s.sociation of pica with two adverse pregnancy outcomes: low birthweight and preterm birth in a group of women from Texas, US. This study found a wide range and a high prevalence of pica if it was more broadly dened than usual; normally pica is used to refer to the craving for and practice of eating soil, clay or dirt. In 81 particular, the pica sample comprised those eating: ice, 53.7 per cent of their sample; ice and freezer frost, 14.6 per cent; other substances such as baking soda, baking powder, cornstarch, laundry starch, baby powder, clay or dirt, 8.2 per cent. Those reporting no pica as dened in this way only amounted to 23.5 per cent of the sample. Women in all three pica groups had lower iron levels at delivery but there were no differences in mean birthweight. In the UK, pica is rarer; our study (Pattison and Bhagrath, 2003) found only three women who experienced craving for non-food substances, all of whom came from non-European ethnic groups and none of whom actually ate the substances they craved.
So there is little evidence that pica attenuates dietary deciencies, though this may be the belief of women who practice it (Ukaonu et al., 2003); in fact it probably increases them. A meta-a.n.a.lysis of pica research found that ethnicity was the most important predictive variable (Simpson et al., 2000). Geissler et al. (1999) showed a strong a.s.sociated between pica and anaemia and iron depletion in women from Kenya. The women themselves described soil-eating as a predominantly female practice with strong relations to fertility and reproduction. They made a.s.sociations between soil-eating, the condition of the blood and certain bodily states. The beliefs women held about eating soil reect both a kind of dietary deciency thesis and the protection against illness thesis explored below. Geissler et al.
emphasise the importance of social and cultural contexts for how women interpret the experience of pregnancy. They conclude that pica is not simply a behavioural response to physiological need but rather that it is a rich cultural practice. Most western cultures regard pica as deviant and repulsive; Lopez et al. (2004) describe pica as adisorder'. Its practice is therefore secret and hidden and Henry and Kwong (2003) argue that pica is stigmatised in American society because of the meaning of dirt in that culture. However, they also argue that the consumption of vitamins and dietary supplements const.i.tutes a similar type of behaviour, done for similar reasons, albeit that it is regarded differently in health terms.
In contrast to pica, nausea is experienced by pregnant women of many cultures. In studies in the developed world, the majority of women report experiencing some nausea. A cross-cultural a.n.a.lysis by Flaxman and Sherman (2000) revealed 20 'traditional' societies in which morning sickness has been observed and seven in which it has never been observed.
As we discuss below, there is evidence that nausea affects food choice and is related to food aversions. However, the theory or belief that nausea and vomiting in pregnancy protect women from ingesting certain vegetables or foods that cause congenital abnormalities and other adverse outcomes of pregnancy is questionable. There have been a number of studies exploring the links between nausea, dietary intake and pregnancy outcome in terms of miscarriage or birthweight. Several of these have found no signicant a.s.sociation between them (Brown et al., 1997; Hook, 1978; Walker et al., 82 1985; Wijwardene et al., 1994) but Lee et al. (2004) found an a.s.sociation between even mild morning sickness and birthweight, and concluded that this was because it reduces dietary diversity and nutrient intakes. A study carried out in the US suggested that the women with the most extreme condition (hyperemesis gravidarum) had babies of lower gestational age and had longer antenatal hospital stays (Paauw et al., 2005).
In our own work (Pattison and Bhagrath, 2003, 2004), nausea and vomiting were the most common symptoms affecting food choice; most women responded by avoiding altogether foods they a.s.sociated with nausea.
Reasons that were cited for aversions in a study among Saudi women were smell (9.4 per cent), vomiting (28 per cent), diarrhoea (2.5 per cent), undesirable effect on foetus (7.8 per cent) and heartburn (18.7 per cent) (Al-Kanhal and Bani, 1995).
Dietary aversions usually occur earlier in pregnancy than do cravings and are frequently reported as being more severe. The most common aversions in US samples appear to be towards alcohol, coffee, meat and foods which have a distinct avour or smell, for example spicy foods or Italian foods (Hook, 1978; Pope et al., 1992). Pope et al. (1997) found that many of the adolescents they studied (66 per cent) experienced aversions during pregnancy towards previously liked foods. The most common aversions were to meats, eggs and pizza and led to decreased consumption of these foods. In our study too (Pattison and Bhagrath, 2003), 72 per cent of women developed aversions to food. The most commonly reported aversions were to meat (20 per cent) and spicy foods (20 per cent), though a small number (3 per cent) had developed an aversion to fruit and vegetables. Aversions were usually linked to nausea, with the smell or taste of these foods inducing nausea and/or being a.s.sociated with an incidence of vomiting.
This pattern of aversion suggests that rather than being a specic characteristic of pregnancy, aversions could reect a way in which women respond generally to foods that they a.s.sociate with nausea. It is well known that people generally can develop aversions to foods through a process of a.s.sociative learning. Whether or not the food was the cause of the nausea, the coincidental a.s.sociation of a bout of nausea or vomiting with a food is enough to create an aversion. In other words, nausea is created by hormonal changes during pregnancy but women interpret this symptom in the same way they would at other times and develop a taste aversion. Data to support this come from a study by Bayley et al. (2002) who studied the temporal a.s.sociation between the rst occurrences of nausea, vomiting, food cravings and food aversions during pregnancy. Of the women in their sample, nausea and vomiting were reported by 80 per cent and 56 per cent respectively, and food cravings and aversions by 61 per cent and 54 per cent respectively. Cravings and aversions were not related. There was a signicant positive correlation between week of onset of nausea and of aversions. In 60 per cent of women reporting both nausea 83 and food aversions the rst occurrence of each happened in the same week of pregnancy. No such a.s.sociation was found for cravings.
In the developed world, while pica is very uncommon, other cravings and aversions are common and rather prosaic. Pope et al. (1997) found that their US sample most frequently reported cravings for: sweets, especially chocolate; fruit and fruit juices; fast foods; pickles; ice cream; and pizza. Adolescents craving sweets during pregnancy consumed more sugar than those who did not crave sweets. Cravings generally resulted in increased intake, and aversions led to decreased food consumption. In our study (Pattison and Bhagrath, 2003), 62 per cent of women reported cravings. The most popular food craved was chocolate (32 per cent) and other foods craved were generally high carbohydrate and/or high fat foods, that is, bread, pasta, ice cream, chips, fruit, meat and what was generically termed 'McDonalds' (5 per cent of the sample). As in the study reported earlier (Pope et al., 1997), the women with cravings had increased their intake of these foods, with 91 per cent having consumed the food they craved in the 24 hours before they were interviewed.
It is clear then that cravings can have a signicant role in diet during pregnancy as they may increase total intake of food or change the proportion of foods eaten. However, cravings are not exclusive to pregnancy.
They are frequently reported in the general population and typically tend to involve foods high in sugar and/or fat, such as chocolate (Yanovski, 2003). So, can cravings in pregnancy be regarded as an extension of a normal experience?
There are two relevant theories as to why cravings develop and why they endure (Cepeda-Benito and Gleaves, 2001). The rst suggests that substances in the food supply a dietary imbalance. This imbalance may be caused in various ways, for example by dieting or by a nutritional de- ciency. This is the theory that most closely links to the dietary deciency hypothesis outlined above. So the increased need for calories in pregnancy, for example, would cause cravings for high calorie foods. The second type of craving theory is that of ncentive hypothesis' of craving. This suggests that cravings are a result of learning what foods produce feelings of wellbeing. This theory suggests that people have cravings for these particular foods because they have learned that the consumption of particular foods leads them to feel good. In psychological learning theory terms, they have learned to a.s.sociate the food with positive reinforcement. This reinforcement can either take the form of physiological or psychological reinforcement (Wise, 1988).
The incentive hypothesis is supported by research into chocolate craving.
In both the UK and the US, chocolate is widely reported to be the most commonly craved food. Michener and Rozin (1994) refuted the suggestion that this is because of the psycho-pharmacologically active substances in chocolate (e.g. caffeine), as they found that capsules containing the same 84 substances did not reduce cravings. It seems most likely that chocolate tastes and smells good to people. Rogers and Smit (2000) concluded that chocolate is simply a common example of the kind of food which people tend to a.s.sociate with pleasant taste, smell and texture, that is, one that is high in fat and sugar. Hill and Heaton-Brown (1994) looked at food cravings in healthy, non-binge-eating women. They found that the most frequently craved food was chocolate (high fat, high carbohydrate), with cravings for savoury foods, such as pizza, being much less frequently observed. In contrast to the accounts given by pregnant women, the food cravings reported by these women were seen as positive, pleasant, hunger-reducing, mood-improving experiences rather than reecting any biological need. So despite differences in the beliefs that pregnant and non-pregnant women have for their cravings, the cravings themselves are for similar types of food. Furthermore, Crystal et al. (1999) found a signicant a.s.sociation between experiencing cravings and aversions prior to pregnancy and experiencing cravings and aversions during pregnancy.
A number of more general studies suggest that women's diet during pregnancy is strongly inuenced by their tastes and eating habits before pregnancy. Mathews and Neil (1998) studied 774 women in the early stages of pregnancy and found that their dietary intake was very similar to that of non-pregnant women and accordingly they were short of some nutrients thought to be important for foetal health. Perhaps the most striking results in this regard come from a qualitative study of the diets of pregnant teenagers for the Maternity Alliance and the Food Commission in the UK (Burchett and Seeley, 2003). They gave detailed accounts of the reasons why they did not eat foods that they regarded as healthy, and the most common reason, given by nearly half of the teenagers, was dislike of that foodstuff. Cost was also a factor for a fth of them and a number also said that the foods were unfamiliar or not offered in their homes. Other reasons for avoiding healthy foods were the effort required to buy them and cook them.
In summary, most of the research on aversions and cravings in pregnancy has stemmed from the a.s.sumption that the dietary behaviour of pregnant women is a direct result of pregnancy. So aversions and cravings are a.s.sumed to result from biological processes which protect women from infection and restore dietary deciencies. Although there may be some merit in this approach, it ignores the lifetime of experience that women have had with food, particularly in relation to cravings. So is this a time when women feel less restrained in their eating?
Restrained and unrestrained eating Unlike diet in pregnancy, the concept of dietary restraint has been widely studied by psychologists. Dietary restraint refers to the tendency to restrict 85 food intake, usually in order to lose weight, or to maintain slimness. It is a volitional but stable behaviour. Herman and Polivy (1983) developed theboundary' model of eating behaviour, which suggests that two physiological boundaries determine when people start and stop eating: hunger and satiation. However, restrained eaters have another self-imposed boundary, which overrides the other boundaries the diet boundary, that is, the amount of food (or calories) that restrained eaters believe they should consume. This diet boundary overrides the normal hunger and satiation boundaries. Dietary restraint is common in women in western cultures as evidenced by the high proportion of women who report dieting at any one time. It is beyond the scope of this book to give a detailed account of the impact of pregnancy on severe eating disorders. Here we will look at the evidence that what might be termed 'normal' dieting behaviour before pregnancy has an impact on what and how much women eat during pregnancy. Pregnancy might be a time when social pressures for slimness could be expected to be relaxed, thus resulting in reduced weight concern despite an increase in body size. Women may therefore be less restrained in terms of what and how much they choose to eat, causing weight gain to be higher. On the other hand, restrained eaters may remain subject to the cultural pressure to be slim and continue or even increase their dieting behaviour. Similarly, restrained eaters may be happy with their pregnancy shape, as it is something apart from their normal experience, or restrained eaters may see the weight and size gained in pregnancy as distasteful. The evidence on both these issues is contradictory.
Davies and Wardle (1994) evaluated body image, body satisfaction and dieting behaviour in pregnancy, expecting women to feel less social pressure to be slim. Pregnant women certainly had a lower 'drive for thinness', had lower body dissatisfaction and rated themselves as less overweight than non-pregnant comparisons. However, they showed similar preference for size of gure to non-pregnant women. These ndings suggest that pregnancy is a time of relaxation in concerns about weight, but that this change is temporary and does not override women's general beliefs about their ideal weight and body shape. Davies and Wardle's ndings chime with our study (Pattison and Bhagrath, 2003).
We did not measure dietary restraint directly; however, the women we interviewed were signicantly more likely to be satised with their pre-pregnancy shape than current shape. And those who were more satised with their pre-pregnancy shape were more condent they could regain it. This suggests that the women who had experience of successful weight control before pregnancy were condent in their ability to exercise such control again.
Clark and Ogden (1999) investigated the role of dietary restraint in mediating changes in eating behaviour and weight concern in pregnancy.
They also compared pregnant and non-pregnant women. The pregnant 86 women reported eating more, showed lower levels of dietary restraint and were less dissatised with their body shape than the non-pregnant group.
They also showed higher eating self-efcacy, that is, the belief that one can control one's own eating. The pregnant women rated themselves as less restrained in their eating behaviour than they had been immediately before their pregnancy and nearly half reported eating more. Clark and Ogden also found that the previously restrained eaters, when pregnant, rated themselves as signicantly less hungry and having greater eating self-efcacy than the non-pregnant restrained eaters. They were comparable in these regards to non-restrained eaters. The results showed no effect of restrained eating on weight change. Clark and Ogden concluded that for women who normally restrain their eating, pregnancy both legitimises an increased food intake and removes previous intentions to eat less.
But other studies contradict these ndings. For instance, Conway et al.
(1999) studied dietary intake and weight gain during pregnancy in relation to dietary restraint in a longitudinal study of women from early to late pregnancy. In their study, current dietary restraint was measured (i.e.
restraint employed during pregnancy). They found that restrained eaters were less likely to experience weight gains within the recommended range for their pre-pregnancy body ma.s.s index (a ratio of height to weight). This went either way such that some gained more weight and some less weight than recommended. DiPietro et al. (2003) studied pregnant women's weight-related att.i.tudes and behaviours in relation to several psychological and social characteristics. This was not a longitudinal study, rather women's att.i.tudes about weight gain were a.s.sessed once at 36 weeks of pregnancy Several variables had been a.s.sessed prior to this, namely anxiety, depression, social support, emotionality and perceived stress (pregnancy-specic and non-specic). Twenty-one per cent of the women were restricting their food intake in some way during pregnancy. The women who reported more restrictive behaviours were more anxious, depressed, angry, stressed and felt less uplifted about their pregnancies in general. Those women who were more positive about their bodies during pregnancy felt better about their pregnancies in general. They also were less depressed and felt less angry. On the other hand, women who were self-conscious about their pregnancy weight gain felt more ha.s.sled by their pregnancies and felt greater anger, though they also reported more support from their partners. Women's feelings about their weight gain were not related to their body ma.s.s index before their pregnancy. The authors noted that negative att.i.tudes about weight gain existed among women who gained weight within the recommended ranges. All this suggests that women's att.i.tudes to weight gain during pregnancy are related to their general feelings about their pregnancy and psychological health rather than to their general feelings about their weight and their eating habits during pregnancy. A number of other studies have also found that women with a 87 history of dieting are less satised with their bodies during pregnancy than those who do not normally diet (Abraham et al., 1994; Fairburn and Welch, 1990; Wood Baker et al., 1999).
So why do different studies have contradictory ndings on the inuence of women's dietary restraint before pregnancy? One obvious difference between studies is whether they involve women who restrained their eating before pregnancy (e.g. Clark and Ogden, 1999) or refer only to women who restrained their eating during pregnancy (e.g. Conway et al., 1999).
These may well represent different groups of women, or the latter may be a subset of the former. However, other reasons for contradictory ndings may lie in more recent theories of dietary restraint.
Recent work has established that dietary restraint itself is not a unitary phenomenon and can be applied in different ways. Joachim Westenhoefer proposes that there are two types of restraint: exible and rigid. These two styles may lead to different strategies for dietary change during pregnancy.
Flexible restraint involves adaptation to the current circ.u.mstances, so while food intake is carefully controlled overall, if large amounts of food, or high calorie foods, are eaten on one occasion, this is compensated for by eating less on a later occasion. Rigid restraint on the other hand is an all or nothing' approach. Rigidly restrained eaters tend to diet frequently, but if they do eat foods that they feel they should avoid, then they do not compensate by eating less. These are the cla.s.sic type of restrainers cla.s.sied by Herman and Polivy (1983) as exhibiting thewhat the h.e.l.l' effect. One implication of this for diet during pregnancy is that rigidly restrained women, once they have veered away from a weight control diet, may be expected to give up weight control entirely. The main reasons why rigid restrainers may stop restraining what they eat are the lack of social pressure to be slim and the sanction of eating forbidden foods because of cravings. Herman and Mack (1975) discovered that an important characteristic of restrained eaters is that they can be induced to eat more than non-restrained eaters if they rst consume apreload' usually a sweet high calorie drink. However, Westenhoefer et al. (1994) found that exible restrained eaters ate less following eating the preload than did rigid restrained eaters. Presumably this mimics their normal eating patterns.
So exible eaters make up for eating a high calorie food by eating less or low calorie foods, whereas once rigid eaters breach their 'diet boundary'
they do not seem able to control their eating. It is noteworthy that most craved foods during pregnancy have high sugar content and are high in calories. If rigidly restrained eaters eat craved foods one would predict that this would act like a preload, and they would not compensate for it.
Flexible restraint is a.s.sociated with the absence of overeating more generally and low levels of depression and anxiety (Smith et al., 1999). If the partic.i.p.ants in different studies of eating during pregnancy involve different types of restrained eaters, or a mixture of the two, they should 88 nd different patterns of restraint and different levels of weight control.
Unfortunately, studies of dietary change in pregnancy have not provided conclusive evidence on this yet.
Advice, recommendations and food scares During the last century the majority of medical authorities recommended that weight gain during pregnancy should not exceed 9.1kg, primarily to prevent the development of maternal toxaemia, foetal macrosomia and caesarean deliveries. These recommendations increased to 11.4kg in the 1970s because it was felt that insufcient weight gain could contribute to premature births and to low birthweight babies born at the expected date.
However, in 1990, an inuential report from the Inst.i.tute of Medicine in the US (U.S. Inst.i.tute of Medicine, 1990) recommended weight gain ranges of 11.415.9kg with the primary goals of improving infant birthweight and ensuring the best outcome for the mother. These weight gain recommendations vary according to the pre-pregnancy weight to height ratio as measured by body ma.s.s index (BMI). However, a signicant number of normal weight women and an even greater proportion of overweight women in the US exceed these guidelines (Abrams et al., 2000). In fact, published studies suggest that only 3040 per cent of women have weight gains within the Inst.i.tute of Medicine's recommended ranges, with some gaining less weight than recommended but most gaining more weight than the guidelines suggest they should (International Federation of Gynaecology and Obstetrics, 1993).
In countries such as the US and UK, midwives and other health professionals see it as part of their role to offer advice on diet and weight gain, so why is this advice apparently not acted on? Is it so difcult to follow? As we have discussed above, there are various factors which inuence dietary behaviour which may lead to weight gain above or below guidelines, such as dietary beliefs, cravings and aversions. However, the nature of the advice that women receive and their interpretation of that advice may also inuence behaviour. As we also discuss in relation to physical activity in the next chapter, advice given by midwives and publications for pregnant women is often vague, recommending ahealthy diet'. Here, as in the general population, if health education messages do not t lay health models, they are less likely to be taken up (Ikeda, 1999; Lupton and Chapman, 1995). In other words, the form and content of the advice, the language used and directions for how to act on the advice have to be understood and integrated into what the woman knows and believes.
For example, American adolescents interviewed by Skinner et al. (1996) said they would prefer to watch a video with atalking baby' or teenage actresses presenting the information than read a leaet or book. They also wanted more information about food than nutrients.
89.It should also be remembered that health professionals are not the only sources of advice; women have access, to varying degrees, to information from family, friends, magazines, books, television and other media and increasingly to the internet. For example, Lewallen (2004) found that family members were a common source of advice for low-income pregnant women in the US, and in our study of a varied group of women in the UK (Pattison and Bhagrath, 2003), less highly educated women and women from minority ethnic groups were less likely to use books, magazines and the internet. These variations are important because the type and content of advice from different sources vary and may conict.
The majority of women in Norman and Adams' (1970) study reported that they had made changes in their diet because of dietary advice from health professionals. Orr and Simmons (1979) a.s.sessed patients'
satisfaction with dietary advice received and found that the majority of patients expressed satisfaction with the amount of information received. A study by Cogswell et al. (1999) revealed that reported advice during pregnancy is strongly a.s.sociated with actual weight gain. However, about half of the women in their study reported having received no advice, or inappropriate advice from healthcare professionals about weight gain during pregnancy: Overweight women were more likely to report having received advice to gain weight greater than the recommended amount during pregnancy. What these studies have in common is that the reported behaviour ts in with the reported advice. Thus, women have created a narrative which is internally consistent, sanctioning behaviour by providing an account of ofcial advice.
In our study (Pattison and Bhagrath, 2003) 30 per cent reported having received no advice from their midwife or general pract.i.tioner, something we return to in the discussion of advice on activity in Chapter 6. The majority of women who remembered receiving advice said they would have liked more than simply being advised to eat healthily' and explanations of why certain foods should be avoided. Women who were more highly educated and expecting their rst child were most likely to seek out alternative sources of information, particularly books, magazines and the internet. Often, nutritional advice is given in antenatal clinics, however not all women actually attend these clinics and the women who do are usually found to be of higher than average socioeconomic, educational and occupational status, characteristics which are also found to be a.s.sociated with already better than average nutritional knowledge and dietary practices (Fowles, 2002). This implies that populations that are more in need of additional advice and information are less likely to receive it.
Midwives in the UK no longer specify optimum levels of weight gain for most women, and for several years women were not weighed. Fowles (2002) found that most women had inadequate general nutritional knowledge and therefore, hardly surprisingly, their dietary intake did not meet all 90 the nutritional requirements of pregnancy. Women are usually encouraged to improve their diet during pregnancy but information on how to improve diet is vague. Most advice mentions fresh fruit and vegetables or eating abalanced diet'. However, this kind of advice, to simply eat 'more healthily'
throughout pregnancy, is not sufcient if women do not have the knowledge for it to act as a prompt to particular behaviours. Furthermore, as we have discussed above, traditional beliefs about what const.i.tutes a healthy diet during pregnancy are likely to be at odds with current nutritional theories.
The vagueness of advice on positively improving diet during pregnancy is in stark contrast to advice on what should be avoided. Often starting as food scares in newspapers, or on television and radio news programmes, advice about avoiding hazardous foodstuffs is often extremely specic. As we said in the introduction to this chapter, pregnant women often nd themselves the focus of food scares. They may be a specic focus of information because a link has been made between a food and foetal or, more rarely, maternal health. They may also be targeted because they are perceived as vulnerable to health hazards. Women are more vulnerable, of course, during pregnancy because of their suppressed immune system (necessary so their body does not reject the foreign tissue of their baby).