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5 February 2014

Analysis: Drinking in pregnancy – what do we know?

Health professionals and policymakers are drawing increasing attention to women’s alcohol consumption during pregnancy: to the point where women who are pregnant, or thinking of becoming pregnant, are officially advised to abstain from alcohol altogether. But how much do we know about the effects of alcohol upon the developing fetus? And does this justify the current guidance?

1) What is the official advice given to women about drinking in pregnancy?

Since 2007, the English Department of Health (DH) has advised that ‘pregnant women or women trying to conceive should avoid drinking alcohol’. This was a shift from previous advice, which advised pregnant women not to drink ‘more than one or two units of alcohol once or twice a week’. The 2007 advice added:

‘If they do choose to drink, to minimise the risk to the baby, they should not drink more than one to two units of alcohol once or twice a week and should not get drunk.’

The advice caused some controversy: particularly because, as the DH admitted, there was no new evidence to support the change. Rather, the recommendation of abstinence was justified on the grounds that women might not understand what was meant by advice to drink more moderately. Then Deputy Chief Medical Office Dr Fiona Adshead explained:

‘We have strengthened our advice to women to help ensure that no-one underestimates the risk to the developing foetus of drinking above the recommended safe levels… The advice… is now straightforward and stresses that it is better to avoid drinking alcohol completely.’

To advise pregnant women, and those who are even thinking of becoming pregnant, to abstain from alcohol completely is a fairly drastic measure. It forbids these women from doing something that, until they decided to conceive, may have been a very normal and important way of relaxing and socialising. For women who ‘do choose to drink’ at low or moderate levels, or women who drank before they discovered they were pregnant, the injunction that ‘it is better to avoid drinking alcohol completely’ instils feelings of guilt and anxiety.

The claim that pregnant women cannot tell the difference between sipping small amounts of wine and heavy drinking is fairly insulting to women. So why did the DH – and other organisations, such as the British Medical Association and the Royal College of Midwives – change their position on the amount of alcohol that pregnant women can safely drink? The one thing we know for sure is that it was not because of any new evidence that low to moderate levels of drinking have a harmful effect on the fetus.

2) What does the evidence say?

It is important to emphasise that the controversy surrounding official advice about drinking in pregnancy relates to low to moderate levels of drinking, rather than heavy drinking. As we discuss below, the consensus that heavy drinking can cause problems in the developing fetus is based on evidence about particular birth defects observed in some babies born to alcoholic women - though even this is a complex association involving a number of factors.

There remains no evidence, however, about the effects of low to moderate levels of alcohol on the developing fetus: and this is the crucial point. Most pregnant women are not alcoholics, but many women drink, and pregnant women have historically enjoyed a drink over the long nine months of pregnancy. Indeed, not so long ago some alcohol intake (most notably, Guinness) was positively encouraged by the medical profession.

In 2007, the British Medical Journal published a debate on the question ‘Is it all right for women to drink small amounts of alcohol in pregnancy?‘ Pat O’Brien, obstetric consultant at University College London Hospitals, answered ‘Yes’, and explained:

‘[T]here is still no evidence that low to moderate alcohol intake in pregnancy has any long term adverse effects. But don’t take my word for it. Last year the Royal College of Obstetricians and Gynaecologists concluded a comprehensive analysis with the view that “There is no evidence of harm from low levels of alcohol consumption, defined as no more than one or two units of alcohol once or twice a week.” In 2003, the Midwife Information and Resource Service updated their evidence based advice: “Women can be reassured that light infrequent drinking constitutes no risk to their baby.”’

O’Brien continued:

‘The Medical Council on Alcohol reached a similar conclusion, and a report in 2006 from the National Perinatal Epidemiology Unit in Oxford found “no consistent evidence of adverse health effects from low-to-moderate prenatal alcohol exposure,” although it did add that the current evidence is not robust enough to rule out the possibility completely. The most recent review, published in September 2007 in draft form by the National Institute for Health and Clinical Excellence advises that, based on current evidence “pregnant women should limit their alcohol intake to less than one standard drink (1.5 UK units or 12g of alcohol) per day and if possible avoid alcohol in the first three months of pregnancy. It would appear that drinking no more than 1.5 units per day is not associated with harm to the baby.”’

O’Brien’s impressive list of evidence indicates that there has been a great deal of attention paid to the effects of alcohol upon the developing fetus – and indeed, attempts to try and establish an effect between low to moderate drinking and adverse outcomes. And yet, no such clear evidence has been found.

Even Vivien Nathanson of the British Medical Association, who wrote the counter-argument to O’Brien in the BMJ, acknowledged that ‘[t]here is currently no consensus on the level of risk or whether there is a clear threshold below which alcohol is non-teratogenic’, and explained: ‘Because there is no conclusive evidence that one to two units of alcohol a week is harmful to the developing fetus, the guidance has until recently recommended an upper limit of this amount.’

Nathanson, like the Department of Health and other organisations advocating alcohol abstinence in pregnancy, bases her position on a precautionary approach. This essentially presumes that the lack of evidence about harm caused to the developing fetus by low levels of alcohol exposure does not indicate that there is no harm; rather that the degree of harm has yet to be discovered. This is a dangerous approach for medical bodies to take.

It is well known that it is impossible for scientific evidence to ‘prove a negative’, in that research will never show that something causes no harm at all. What scientific research can show is whether a certain substance does cause harm, and in what doses or contexts.

Research into Fetal Alcohol Syndrome has not shown that alcohol causes birth defects, but it has shown compellingly that there is an association between large amounts of alcohol (in pregnant women known to be alcoholics) and certain birth defects in some of the babies born to those women. From this it is reasonable to hyphothesise that high levels of alcohol can have an effect on the fetus – although as we indicate below, even this does not prove that alcohol is the sole, causative determinant of FAS.

But it is not reasonable to presume from this that any alcohol in any pregnant women must therefore have some malign effect. This is particularly true given that a large body of research has failed to find evidence of harm from low levels of drinking. Ignoring the evidence in order to promote a message to women that merely seems to be right is unscientific, dishonest, and dangerous.

3) What is Fetal Alcohol Syndrome?

Fetal Alcohol Syndrome, or FAS, is a complex condition that was first labelled in the USA in 1973. It denotes a collection of features including retarded growth, pre- or postnatally; a number of facial abnormalities; and intellectual impairment or developmental delay, and was observed in babies born to alcoholic women. However, while FAS has been associated with very heavy drinking in pregnancy, it does not occur in all babies born to alcoholic women. Nor does the label FAS tell us everything about the cause of this condition.

The US scholar Elizabeth Armstrong, in a 1998 article on ‘the discovery and evolution of Fetal Alcohol Syndrome’, explains the complexity of FAS like this:

‘In the case of FAS, the single-minded focus on alcohol as the sole cause of the observed outcome blinded doctors to the social context in which prenatal exposure to alcohol occurred and to any potential ameliorating or exacerbating factors. Every woman was equally at risk; yet, that assumption contradicted research findings that suggested that even among chronic alcoholics, not every woman would have a baby with FAS. Moreover, some studies suggested that the appearance of the syndrome could be heavily influenced by other maternal characteristics. For example, one study that examined women who had at least three drinks a day during pregnancy found a rate of FAS of 71% among children of low-income women, compared with a rate of only 4.5% among women of higher socioeconomic status. The key difference between these two groups was their nutritional status during pregnancy.’

In other words: many factors, including nutrition and poverty can affect whether a fetus develops the kind of anomalies associated with FAS. It is not simply about the mother’s alcohol intake, and cannot be explained by that alone.

The complexity of FAS as a condition, and the fact that it appears rarely even in the small subgroup of women who drink very heavily during pregnancy, means that FAS was initially described as a rare condition. ‘The first prospective study [published in 1980] showed that FAS was a rare outcome of maternal alcoholism during pregnancy, an observation subsequently confirmed by numerous investigators,’ explained Armstrong and Abel in 2000. Armstrong’s 1998 article notes that there has been a long-standing ‘debate about moderate drinking vs. “alcoholism’’ as a risk factor for FAS’, and cites a letter to the editor of The Lancet, published in 1979, which ‘questioned “why the syndrome remains rare while social drinking during pregnancy is so common”’.

However, as Ellie Lee notes in the new book Parenting Culture Studies, the problem of FAS ‘is now presented in terms that construe it neither as complex, nor rare. Women are told that any drinking in pregnancy is the cause of most health and developmental problems in children.’ How has this case been made?

4) How is Fetal Alcohol Syndrome presented today?

The message promoted to pregnant women today is that drinking any amount of alcohol in pregnancy can lead to a range of problems with their babies, which go far beyond the symptoms associated with FAS. These range from lowered IQ to mood disorders, sleep disorders and behavioural disorders, and are categorised under the wide-ranging label of ‘Fetal Alcohol Spectrum Disorder’.

In this way, women are encouraged to view any problem that their child develops as somehow related to the amount of alcohol she drank during pregnancy. The lobby group National Organisation on Foetal Alcohol Syndrome (NoFAS), for example, claims that alcohol use during pregnancy is ‘the leading preventable cause of birth defects, developmental disabilities and learning disabilities’.

It is worth dwelling on the difference between the initial diagnoses of FAS, and the approach taken by organisations such as NoFAS. The initial labelling of FAS came out of the identification of babies with particular, clear and severe disorders, born to a group of women known to be heavy drinkers, and from there it was discovered that there was an association between heavy alcohol use and birth defects in some women. By contrast, the argument that alcohol is the ‘leading preventable cause’ of a wide range of disabilities, ranging from physical abnormalities to emotional or behavioural problems and also ranging in severity, is used to draw an association between any problem a child might have and any alcohol consumption in pregnancy.

It should be obvious that this is a specious argument. Even women who abstain completely from alcohol during pregnancy – as many women increasingly do – give birth to children who develop the kind of problems described by NoFAS as ‘Fetal Alcohol Spectrum Disorder’. The presumption of NoFAS’s argument is that if women abstained during pregnancy, these problems would disappear; yet clearly, they would not. As a recent analysis of one study on the NHS Choices website puts it:

‘Childhood emotional development is an extremely complex issue and many parents whose children do develop behavioural and emotional problems will find that they do so for no apparent reason. Often, these types of problems are not somebody’s ‘fault’, they just occur.’ 

The effect of widening the definition of FAS to include any abnormalities or problems exhibited by babies is to reverse the process of causality. Rather than evidence being sought that proves a causal relationship between alcohol and birth defects, the existence of birth defects and a wide range of other problems in some babies is simply treated de facto as evidence that the mother must have drunk some alcohol during her pregnancy, and that her baby’s problems are the result of this.

This claim, that practically all of babies’ problems can be explained by the mother’s alcohol consumption while pregnant (or even before conceiving), is extraordinary, both for its lack of scientific value and for the excess of guilt that it places upon the mother of a baby with abnormalities or other problems. Yet insofar as the Department of Health did use ‘evidence’ to change its guidance in 2007, this was the claim it relied upon.

‘The National Organisation on Foetal Alcohol Syndrome estimates for the UK as a whole that there are more than 6,000 children born each year with Foetal Alcohol Spectrum Disorder,’ stated the DH press release. Immediately, the DH jumped to the supposition:

‘Excessive alcohol can cause damage to the unborn baby at all stages in pregnancy and of course many women don’t confirm they are pregnant until a number of weeks into the pregnancy. Therefore, for women who are planning to conceive it makes sense to avoid alcohol or limit their consumption to no more than 1-2 units once or twice a week.’

5) What about all those news reports about the problems caused by drinking in pregnancy?

Headlines, unfortunately, tend to simplify and sensationalise study findings; and the sheer number of reports tends to create the impression that drinking in pregnancy is a problem. In reality, current studies continue to offer contradictory findings, and contain many of the difficulties that have always been observed.

For example, at the beginning of January 2014, the Daily Telegraph reported on Danish research suggesting that ‘Women who have an occasional drink during pregnancy have children who are better adjusted and better behaved than the offspring of those who abstain’. Other studies have revealed similar findings, and the obvious reason for this is the class difference between mothers who are likely to drink, and those that are not.

One of the study’s authors, Janni Niclasen, a psychologist at the University of Copenhagen, said:

‘My study shows, among other things, that the children of mothers who drank small quantities of alcohol - 90 units or more [the equivalent of a glass of wine a week] - during their pregnancies show significantly better emotional and behavioural outcomes at age seven compared to children of mothers who did not drink at all. At first sight this makes no sense, since alcohol during pregnancy is not seen as beneficial to child behaviour. But when you look at the lifestyle of the mothers, you find an explanation. Mothers who drank 90 units or more of alcohol turn out to be the most well-educated and [have the] healthiest lifestyle overall.’

Three weeks later, the Daily Mail reported: ‘Children “more likely to be badly behaved” if their mother drinks more than two glasses of wine’. This article seems to have been based on a study of the same Danish cohort, by the same researchers, as that which inspired the Telegraph report. And as an excellent analysis on the NHS Choices website explains, the Mail’s headline ‘was attention grabbing, but inaccurate’:

‘The study did not prove that it was binge drinking that affected the child. In fact, there were a number of significant differences in the women who binge drank in late pregnancy and women who didn’t drink, such as income and history of psychological disorders; all of which could have had an influence on the development of the child.’

The NHS Choices analysis went on to note that there were ‘several limitations of this study, most of which were acknowledged by the researchers’, and concluded: ‘In light of the evidence provided in the study it would appear unlikely that a few too many glasses of wine during pregnancy – while certainly not recommended – will permanently influence how a child will develop emotionally in later life’.

The fact that the same study can lead to wildly conflicting headlines is symptomatic of how the jury is still out on the question of exactly how alcohol consumed in pregnancy affects the fetus.

6) What is the effect of official advice on abstention from drinking in pregnancy?

Those who advocate telling pregnant woman to abstain from alcohol completely seem to assume that such advice is benign. The idea is that if a woman doesn’t drink, her baby may not have problems; and if her baby does not have problems, she will know that her drinking is not to blame – so why not just stop drinking?

This view massively distorts both the personal and the policy consequences of policing pregnant women’s drinking behaviour. As noted above, those women who would otherwise enjoy the odd glass of wine but follow the ‘complete abstention’ advice in pre-conception and pregnancy are deprived of an enjoyable, relaxing and sociable activity for over nine months of their pregnancy, without an evidence base.

Meanwhile those women who will have been drinking alcohol before realising they were pregnant, or decided to ‘choose to drink’ their one or two units a week, are incited to feel guilty and anxious, particularly if their baby develops some problems. All the paediatric specialists in the land might rightly reassure women who have babies with anomalies that the causes of most anomalies are complex, and have developed throughout history in women who have never touched alcohol; but so overwrought is the culture surrounding pregnancy today that women will nonetheless worry that that one glass of champagne at their sister’s wedding caused the problem.

The pressure upon women to abstain from alcohol during pregnancy is not merely cultural. At an official level, it is becoming taken as an article of faith that drinking is a marker of, or even form of, abuse of the ‘unborn child’. So far, the extreme consequences of this have happened in the USA, through the use of ‘fetal protection laws’ against allegedly drug-abusing women, but in the UK too there are emerging signs of the law being used to bolster official ‘advice’.

The Sunday Times on 2 February reported on an attempt by lawyers acting for local authorities to gain criminal injuries compensation for children allegedly brain damaged by their mother drinking alcohol during pregnancy, having been warned of the risks. Such laws have huge consequences for women’s reproductive autonomy. If pregnant women are to held criminally liable for the health of their newborn baby, this consolidates the trend identified by Ellie Lee, where ‘pregnant women are now treated as a “class apart” for whom different rules are applied in the informal world of everyday life.’

The broader consequences of this for women’s reproductive rights are chilling. If it comes to be seen as a crime to harm the ‘unborn child’ through drinking alcohol, where does this leave women who wish to end their pregnancy through abortion?

The use of ‘evidence-based policy’ to justify the policing of pregnancy is questionable enough, even where there is compelling evidence that a certain activity is likely to be hazardous. When there is no evidence, as in the case of low to moderate drinking, ‘evidence-based policy’ becomes mere diktat. This discredits policy, and does pregnant women a great injustice.

Women are treated as stupid, with the presumption that they need a ‘straightforward message’ of abstinence, because they cannot be trusted to understand the difference between social drinking and chronic alcoholism. Women are also treated as little more than incubators, obliged to eschew certain pleasures for the sake of creating the optimal womb environment for the baby within.

Further reading:

‘Policing Pregnancy: The pregnant women who drinks’, by Dr Ellie Lee, in the new book Parenting Culture Studies, by E. Lee, J. Bristow, C. Faircloth and J. Macvarish, published by Palgrave Macmillan on 12 February 2014. Order this book here.

There are very good reasons a foetus cannot be a victim of crime. By Zoe Williams. Guardian, 4 February 2014

Taking responsiblity for fetal alcohol syndrome: Criminal Injuries Compensation Authority case. Elizabeth Prochaska discusses the recent court decision about criminal compensation for fetal alcohol disorder. Birthrights, 5 February 2014

Drinking alcohol during pregnancy “could be ruled a crime” – can women be held responsible? Glosswitch. New Statesman, 4 February 2014