General news

Women with a history of eating disorders are at higher risk of major obstetric complications, such as miscarriage and lower birth weight.

This study, published in the March 2007 issue of the British Journal of Psychiatry, investigated the effect of a history of anorexia nervosa (AN) and bulimia nervosa (BN), on the outcome of pregnancy in a representative sample of the British population.

All pregnant women living in Avon, UK, who were expected to deliver their baby between April and December 1992, were recruited. Data were obtained on 14,472 women via postal questionnaires, and 12,254 were included in the study.

At 12 weeks women were asked, among other things, whether they had any recent or past history of psychiatric problems, including depression, schizophrenia, alcoholism, AN, BN or any other psychiatric disorder.

Birth weight, pre-term delivery and miscarriage history were compared in 171 women with a history of AN, 199 with a history of BN, 82 with both, 1166 with other psychiatric disorders and 10,636 with no psychiatric disorders.

It was found that the group with BN had significantly higher rates of past miscarriages, confirming the findings of previous studies. The authors of the study comment that future research will need to address the causes of these miscarriages, and the exact physiology.

The group with AN delivered babies of significantly lower birth weight than the general population, although the weights were comparable to babies of women with other psychiatric disorders. This is the first study to compare these two groups.

The researchers comment that the lower birth weight of babies born to women with AN was mainly due to lower pre-pregnancy body mass index (BMI), and to a lesser extent by smoking in the second trimester of pregnancy.

Smoking during the second trimester seemed to be mainly responsible for low birth weight in women with other psychiatric disorders.

The authors of the study suggest that women with a history of AN should be informed when planning a pregnancy that good general health includes having a healthy BMI, as well as stopping smoking. Women with BN should also be informed about the high risk of miscarriages.

Previous research suggests that the association of smoking with high levels of body image distortion, and the role of smoking in weight control, are relevant to women with and without eating disorders.

If this is so, the link with body image and weight control may need to be considered when counselling women about smoking cessation in pregnancy.