Part 4 (1/2)

However, in this instance the person perceived to be vulnerable is more likely to be the baby; the targeting of the mother stems from their custodians.h.i.+p of their baby's health.

During the period of our study (Pattison and Bhagrath, 2003) there were two main food scares directed at pregnant women. One concerned coffee, which was linked to stillbirth and early infant death in an epidemiological study published in the British Medical Journal (Wisborg et al., 2003).

This nding was taken up by various newspapers and other media in the UK. The second concerned tuna sh, and followed on from previous studies on the mercury content of oily sea sh such as marlin and shark. These other sh do not form a major part of British women's diets. However, when it was found that tuna may also contain high levels of mercury, this information was quickly spread in the media and incorporated into The Food Standard Agency guidelines. Of the women we interviewed only about a third had heard either or both the coffee and tuna stories. However, 72 per cent of those who had heard responded by eliminating or drastically reducing their intake of the food, but the others did not change their consumption at all. This emphasises one of the harmful effects of food scares. While reducing coffee intake is unlikely to harm women, it may make them feel uncomfortable. However, tuna is generally regarded as a healthy food, so the elimination of it is not likely to improve women's diets.

In a survey commissioned by SMA (a baby milk producer) in 2003, 558 mothers with children aged between 12 months and two years in the UK and the Republic of Ireland were questioned about their diet during 91 pregnancy and what they believed about foods that const.i.tuted a healthy diet. The results showed that while they were aware of food scares, they did not always know or understand the research ndings which formed their basis. Some foods were regarded as unsafe through a generalisation from another food. So 60 per cent of women believed that cottage cheese, which is a safe, low-fat source of protein, was unsafe because they failed to make a distinction between this and soft cheeses which may carry listeria. However, in other cases women failed to generalise from one food to others which were similarly hazardous. For example, most avoided or reduced their intake of coffee, because of the risk of caffeine, yet 70 per cent believed that diet cola drinks, which also contain caffeine, were safe.

In one of our studies we also found that women reduced their intake of coffee in an attempt to avoid caffeine, but increased their intake of other caffeine-containing drinks such as tea and cola drinks (Gross and Pattison, 1995).

Research that underpins dietary advice is often presented in a way which makes it very difcult to interpret. Take the following extract from the Babyworld website: Research published in 1999 suggested that high doses of vitamin C and vitamin E may help reduce the incidence of pre-eclampsia in women at high risk of developing the illness. Although this seems encouraging news, most experts remain unconvinced. First, the study was very small (only 160 women completed the study) so the results may not be accurate (a larger trial is being planned).

Secondly, there is some doubt over the safety of the ma.s.sive doses required of the two vitamins.

(Hulme Hunter, 2005) Women who are concerned about pre-eclampsia are advised to talk this study over with their obstetrician. However, the study is unattributed and is so heavily criticised that it would be difcult to imagine any woman feeling comfortable raising these ndings if she does not have knowledge of scientic procedures, or access to medical journals to look up the study. It seems that an attempt not to blind readers with science has led to an oversimplied version, which will only have the effect of making women feel worried.

However, attempting to produce all the caveats and exceptions to advice given is also confusing and likely to make readers worried. Take, for example, the following extract from the BBC website: Research indicates that mothers who eat sh once a week are less likely to give birth prematurely. Oily sh eaten in pregnancy also helps with children's eyesight. However, when you're pregnant 92 have no more than two portions of oily sh a week. Oily sh includes fresh tuna (not canned tuna, which does not count as oily sh), mackerel, sardines and trout. Avoid eating shark, swordsh and marlin and limit the amount of tuna to no more than two tuna steaks a week (weighing about 140g cooked or 170g raw) or four medium-size cans of tuna a week (with a drained weight of about 140g per can). This is because of the levels of mercury in these sh.

At high levels, mercury can harm a baby's developing nervous system.

(Welford, 2005) Again the research is unattributed, and even undated, making it very difcult to trace, and there is not enough information to evaluate it. What const.i.tutes oily sh here is unclear; the pa.s.sage seems to suggest both that women should and should not eat tuna, fresh or canned. In an attempt to be accurate and all encompa.s.sing, the advice becomes controlling.

While information from research that is incorporated into professional leaets and websites may be balanced, much of what appears in the media is not. For example, the research paper referred to above on coffee actually indicated that this was not really a problem for women who were drinking less than eight cups of coffee a day (Wisborg et al., 2003). Similarly, a later report by Bech et al. (2005) suggested that the risk of foetal death was only signicantly higher if women drank more than four cups of coffee a day.

However, as we have shown in Chapter 2, people tend to cla.s.sify things as either safe or unsafe, so the media portrays foods in this way and the likelihood is that, if women act on food scares at all, they will avoid the apparently hazardous foods completely. The distinction between safe and unsafe foods also tends to vary across cultures and be embedded in more general eating habits. So people from European countries tend to regard wine as safe in moderation, whereas it is denitely on the list of things to avoid completely in the US, even though the research evidence on which advice is based is the same.

A nal aspect of food scares to consider is that they nearly always come too late for pregnant women to act on them. Finding out that tuna contains mercury when you are several weeks into pregnancy, and you have already consumed large quant.i.ties of this formerly healthy food, is only likely to induce guilt and anxiety. Neither of these emotions are likely to increase the health of women or their babies. The BUPA website even gives a list of foods that women should have avoided before pregnancy: There are also certain foods that women should avoid pre-pregnancy. These include: liver and large quant.i.ties of vitamin A in supplements, unpasteurized dairy products, 93. raw eggs, pateas, soft cheese.

(BUPA, 2005).

There is little evidence to support this draconian advice and since so many pregnancies are not planned with the precision required by this, many women will not have been able to act on it anyway.

Concluding remarks Research on diet and dietary change during pregnancy is unusual in several respects. One important characteristic is the amount of research which has been carried out in countries other than those in the developed world. While little of this work could be said to be cross-cultural, it does at least give us some insight into how pregnancy is experienced by the women outside the mainstream focus. The differences and similarities between women of different cultures are illuminating in that they show how important it is to consider the context and cultural underpinnings of women's lives.

We have reiterated several times in this chapter that women's eating behaviour during pregnancy is studied out of the context of their everyday lives and history. In particular, little account is taken of dietary restraint and dieting behaviour before pregnancy. Yet at the same time the exception to this is a fascination with the dietary habits of what to most researchers is 'the other', notably pica.

A further unusual feature of research on diet is the direct impact that research has on sanctioning women's behaviour during pregnancy. Epidemiological studies which show some a.s.sociation between what women have eaten during pregnancy and subsequent pregnancy outcomes make almost daily appearances in the media. The risks a.s.sociated with food types are amplied through newspapers, magazines and television, and, perhaps most pervasively, through the internet. Often these studies are later refuted, dealing as they often do with statistically very small increases in risk. However, few women in the developed world can be unaware of the food scares and risk messages directed at them. Yet, what use they make of this information, or the effect of receiving risk messages, often too late to act, on psychological health still goes largely unexplored.

6.KEEPING ACTIVE.

Daily activity and exercise in pregnancy.

I've slowed down. Its common sense really isn't it?

(Gross and Clarke, 2004b: 167).

The 2003 guidelines published by the American College of Obstetricians and Gynecologists (ACOG) on Exercise in Pregnancy and the Postnatal Period state that: 'pregnant women with uncomplicated pregnancies should be encouraged to continue and engage in physical activities . . . exercise has minimal risks and conrmed benets for most women' (ACOG, 2003, cited in Artal and O'Toole, 2003: 8).

This advice, which comes from an established medical authority, is derived from a plethora of research on the potential effects of strenuous exercise on pregnancy outcome and maternal wellbeing. It is such guidelines as these which inform professional advice around the world. The expectations behind such guidelines are that with appropriate medical input, women's health and that of their baby the pregnancy outcome can be a.s.sured. But how relevant is this advice beyond extreme cases, either of high-risk pregnancies, since the guidelines provide many details of contraindications for continuing with exercise, or of a very few high-level athletes. What is the link between such advice and most women's experience?

The research on physical exercise has taken place within a context where the various discourses of pregnancy, both lay and medical, have presented it as a time of moderation and the emphasis has been on the giving up of activities that might put the baby at risk. As we discussed in Chapter 4, there is plenty of advice on how to behave during pregnancy in order to ensure the safety of the pregnancy and to maintain maternal health. By contrast with some of the domains of research we have already discussed (for example paid work, diet), research on physical exercise in pregnancy has instead provided conrmation that physical stresses arising from recreational exercise do not appear to increase the incidence of poor outcomes and in fact may signicantly reduce the risks. The current advice 95 from ACOG and similar authorities is thus a commonsense position that we should be able to endorse and to act upon.

However, rst, these current guidelines represent quite a s.h.i.+ft in the medical literature from previous recommendations of moderation to the present maintenance recommendations, and these still require consultation with professionals. Second, the focus of the guidelines is more on exercise than physical activity more generally and the apparently straightforward statement of encouragement is less easy to translate when all forms of activity are considered. Clearly, women habitually partic.i.p.ate in a combination of occupational, domestic and recreational activities and their experience of pregnancy is effectively a process of negotiating being pregnant within the multiple demands of their daily lives. In this context, therefore, physical exercise programmes may be a very small part of their physical activity. How women with ordinary lives respond to advice to sustain physical activity at the same time as moderating other of their behaviours is more complex than the guidelines alone might suggest.

In this chapter, we look at some of the research evidence that has informed, and continues to inform and update, such guidelines and advice on exercise and activity with a view to identifying the kinds of activity referred to and the nature of the advice that they have produced. Then, through material from our own work on women's activity during pregnancy, we explore how women manage the competing expectations of their behaviour in pregnancy.

Exercise activity and outcomes: infant and mother When investigating the topic of physical activity in pregnancy, there is a wide-ranging literature reporting research on exercise, including work on animals, undertaken from a primarily biomedical perspective, which makes some reference to psychological effects. The research seeks to examine the physiological response of the body in order to identify where risks may or may not occur and the extent to which changes taking place in pregnancy may extend or reduce such risks. For example, a book edited by Artal and his colleagues on Exercise in Pregnancy (Artal et al., 1991) draws on a range of existing expertise to address not only the physiological adaptations to pregnancy, but also the physiology of exercise during pregnancy and, signicantly, the practical applications of this research in terms of advice. The appendix to the book contains what were the current ACOG guidelines at the time the rst edition of the book was produced (1986), which were more cautious in their advice than those cited above. The editors indicate that one of the reasons for caution in both the earlier guidelines and their own conclusions, that they 'no longer have to claim that there is lack of data to allow sage, moderate exercise prescription in pregnancy' (Artal et al., 1991: ix, emphasis added), is the lack of statistical 96 power in some of the studies on strenuous exercise in particular. We shall examine further the concept of permission for women to exercise represented in this statement, once we have looked at the nature of the evidence to which they refer. The historical development of the exercise guidelines is interesting in itself, reecting as it does the available evidence base; the 1994 revision of the ACOG guidelines (ACOG, 1994), though still cautious, by incorporating phrases such as 'should be able to' was more relaxed in tone and even somewhat prescriptive about the value of exercise.

Typically, in research terms, exercise has been used to refer to structured programmes or practices of physical activity, such as those of compet.i.tive and recreational athletes and partic.i.p.ants in organised sporting activities, which can include gym attendance. The increased attention to the value of exercise is reected both in health promotion literature which appears in a variety of media and in the research that has gone on to examine its impact. The benets of physical activity and its relation to physical and psychological health have been increasingly emphasised for all groups (Hagger and Chatzisarantis, 2005). Even in 1991, Artal and Gardin were able to state, albeit rather patronisingly, that 'the exercise spirit has enraptured women of all ages, including women in their childbearing years' (Artal and Gardin, 1991: 1).

The discussion now turns to research on the extent to which physical activity may impact on pregnancy and pregnancy outcome and examines whether or not the traditional consensus of discouraging physical activity can be scientically supported. Coming from very different perspectives, physiologists like Artal, sociologists (e.g. Barker, 1998) and literary a.n.a.lysts (e.g. Hanson, 2004) take the position that, throughout history, recommendations for physical activity in pregnancy have typically been based more on social and cultural expectations than they have on any denitive evidence. Nonetheless, there has been an acc.u.mulation of literature that suggests there may once have been a genuine theoretical basis for reducing exertion.

The central concern is the body and the physiological response to pregnancy since it is clearly the case, as Sternfeld (1997: 34) indicates, that: 'Pregnancy stresses the body more than any other physiological event in a healthy woman's life and requires considerable cardiovascular, metabolic, hormonal, respiratory and musculo-skeletal adaptations'.

The adaptations occur whether or not women are partic.i.p.ating in exercise regimes; the issue is whether the addition of exercise pushes the systems beyond their capacity and thus causes harm, either directly to the foetus or via the impact on maternal functioning. Thus, the medical and safety issues regarding physical activity in pregnancy have been based upon the concern that certain aspects of cardiovascular, metabolic, thermal and mechanical stress could act to threaten outcome.

97.The essential and routine changes in the human circulatory system are quite dramatic in nature and may manifest in many of the unpleasant symptoms of pregnancy including dizziness, nausea and waves of sudden fatigue, but they are not necessarily damaging. As the vascular network expands, increased dilation particularly occurs in the blood vessels supply-ing the skin, kidneys and reproductive tissues. In many ways, the circulatory adaptations induced by pregnancy appear to complement those produced by regular weight-bearing activity in the non-pregnant state; studies of the circulatory effects of regular exercise have demonstrated that vigorous training will increase blood volume and increase the maximum cardiac output that an individual can achieve. It will also increase the density and growth of blood vessels and improve an individual's ability to dissipate heat. Moreover, research evidence suggests that when an adequate exercise regime is maintained during pregnancy, the results of the interaction between these two sources of cardiovascular adaptation are at least additive (Clapp, 1998). Benets for the prospective mother have also been postulated and include what are regarded as signs of tness in nonpregnant individuals: reduced heart rate and reduced blood pressure (Simpson, 1993).

Despite the positive effects of the physiological vascular changes, there nonetheless remained some concerns regarding the capabilities of the human cardiovascular system to meet the dual demands of exercise and pregnancy. As with the investigations of the impact of paid work in pregnancy on outcomes, it could be convincingly argued that this concern and the ensuing research was particularly eurocentric (or Western-centric); many women in the developing world almost certainly continue to undertake strenuous activities that give rise to the same physiological changes as exercise and have little opportunity to choose to moderate such activity.

The main rationale for considering physical stress as a risk factor for poor pregnancy outcome lies in the a.s.sumption that heavy physical effort during pregnancy may divert blood ow from the uterus and, by doing so, reduce oxygen and nutrient delivery to the foetus, or that increase in muscle action will divert effort to the skeletal muscles (McMurray et al., 1993; Stein et al., 1986). Compounding this response further is the proposition that foetal oxygen requirements may increase with strenuous physical work, primarily as a consequence of concurrent increases in temperature and metabolic activity (Lotgering et al., 1985). If this were the case then any reduction in uterine blood ow initiated by physical exertion might be a.s.sociated with a more severe foetal hypoxia than a similar reduction occurring at rest (Bell and O'Neill, 1994), raising alarm bells for the pursuance of maternal exercise at high levels.

However, rea.s.suringly, investigations suggest that the biological system appears to be robust, since several mechanisms have been identied which may act to ensure that foetal oxygen consumption is not easily 98 compromised and the cardiovascular adaptations that occur during pregnancy appear sufcient to maintain adequate blood ow and oxygen delivery to both the exercising muscles and the developing foetus (Clapp, 1980; Rauramo and Forss, 1988). Recent research by Larsson and Lindqvuist (2005) suggests that low-impact aerobics has little or no effect on maternal hyperthermia. From this perspective at least, therefore, it seems that physical activity in pregnancy need not be discouraged. The evidence would, therefore, seem to be at odds with the advice appearing at the time. The basis for such guidelines, to stringently limit exercise during pregnancy, must therefore have arisen from other evidence. This evidence was likely to be that derived from the results of clinical investigations which concentrated directly on the strength of a.s.sociation between activity partic.i.p.ation and pregnancy outcome. In this research, the variables that were considered are those that suggested the greatest foetal risk or poorer foetal outcome and include the standard obstetric parameters of foetal growth, length of gestation and type of delivery. Maternal wellbeing has been addressed, though this received less attention in the rst instance.

In one of the earliest epidemiological studies of recreational activities, Clapp and d.i.c.kstein (1984) observed an adverse pregnancy outcome among women continuing vigorous exercising late into their pregnancy.

Comparisons were made between pregnant women who maintained their exercise until late into the third trimester and those who either reduced their activity or remained sedentary. Women who continued to exercise at an intensity greater than 50 per cent of their age-predicted maximum heart rate for 30 minutes or more, three times a week, were found to exhibit signicantly less pregnancy weight gain and a shorter pregnancy.

The same women also demonstrated a higher incidence of small for gestational age (SGA) babies and a mean birthweight 500g less than either women who were sedentary or women who had stopped exercising prior to the 28th week of their pregnancy. In a similar manner, Clapp and Capeless (1990) later reported that babies born to women who continued to exercise at or above 50 per cent of their pre-pregnancy level were found to weigh an average of 310g less than those who did not. These authors concluded that approximately 70 per cent of the observed variance in infant birthweight could be directly attributed to differences in infant body fat. Typically, infant body fat develops in the last trimester, thus exercise at this time would have appeared to reduce both maternal and infant body fat.

Nonetheless, this work is by no means conclusive since subsequent and already existing research studies found no effects. Rose et al. (1991) did not nd the same rates of lowered birthweight in the babies of women undertaking vigorous physical activity and other studies have reported that physical stress arising from recreational exercise activity does not increase the incidence of either SGA infants or premature labour, and may even 99 decrease the incidence of both (Berkowitz et al., 1983; Klebanoff et al., 1990; Rabkin et al., 1990). Furthermore, case studies of athletes found that they delivered normal birthweight infants despite running regularly throughout their pregnancies (Korc.o.k, 1981). These studies are complemented by laboratory studies which found a similar absence of relations.h.i.+p between work effort or tness on birthweight (Dibblee and Graham, 1983; Wong and McKenzie, 1987).

While the results of such biologically focused research may be criticised for their small sample sizes and insufcient statistical power to detect a true a.s.sociation, as Artal and his colleagues (1991) conclude, nevertheless, the available larger studies have only served to substantiate their ndings.

Hall and Kaufmann (1987) recruited 845 pregnant women, each given the option of partic.i.p.ating in an individually prescribed prenatal exercise programme. Foetal heart rates were monitored throughout the exercise sessions and no abnormalities were observed. Partic.i.p.ants were later categorised on the basis of the total number of exercise sessions they completed during their pregnancy and no adverse effect of exercise programme on gestational age or birthweight was reported. In fact, the authors observed a trend for birthweight to be higher in the exercise group.

Moreover, greater amounts of exercise were revealed to be a.s.sociated with a reduced incidence of caesarean section, higher infant Apgar scores (a composite rating of colour, breathing, heart rate, movements and reexes normally a.s.signed one and ve minutes after birth) and shorter hospitalisation. In this instance, therefore, higher levels of physical activity actually appeared to be of benet. Research has conrmed that labour and delivery appear to be shorter in women who exercise regularly (Clapp, 1990), although the contradictory nature of these ndings also shows that in a cohort of runners there was a higher likelihood of caesarean delivery (Dale et al., 1982). However, in an Australian study of perinatal outcome in a low-risk obstetric population, referred to in Chapter 4, Magann and colleagues (2002) contribute to the confusion by nding that exercise in working women was a.s.sociated with smaller babies, increased incidence of induction of labour and longer labours.

Nevertheless, the c.u.mulative result of this research provides little indication of a negative relations.h.i.+p between higher levels of physical activity and adverse pregnancy outcome. Most studies demonstrate neutral if not favourable a.s.sociations between maternal tness and length or type of delivery and although there are clearly studies which do give cause for concerns about pregnancy outcome it may be that the differences are small despite their statistical signicance. Of course, if there are other risk factors present, a small difference arising from exercise may be compounded and the medical concerns would be legitimate as there could be serious reper-cussions for both mother and baby. But, what about the possible impact on maternal health and wellbeing?

100.As the ndings from the studies indicate, physical exercise may well be benecial in terms of labour and delivery. More than this, it may also be of direct physiological benet, in terms of aerobic capacity (Sternfeld, 1997).