Reprinted from Eating Disorders Review
January/February 1999 Volume 10, Number 1
©1999 Gürze Books
Women who become pregnant while being treated for an eating disorder are likely to accept help and to progress through pregnancy with a good outcome for their babies and themselves. Women receiving treatment also have more awareness of the effects of the disorder on their body, better insight into their beliefs, attitudes and behavior, and are more likely to respond to dietary advice during pregnancy.
Very few women with eating disorders are unable to accept weight gain during pregnancy. Those who cannot may need to be treated in a hospital until they can gain sufficient confidence that they are in control of their eating. A woman who is underweight but feels she overeats needs help to achieve a more realistic understanding of the amount she needs to eat, and to learn ‘normal eating behavior.’
Complications of Pregnancy
Mothers who have recovered from an eating disorder are no different from those who have never had disordered eating. That is, they do not have a greater incidence of miscarriage, hyperemesis gravidarum, or delivery of growth-retarded low birth weight (LBW) babies. These complications of pregnancy are only increased in women with an eating disorder that is active at the time of pregnancy.
Since women with active eating and exercise disorders are also more likely than other women to seek help for infertility, there is also a good opportunity to counsel these women at this time.
Obese and Overweight Women
Not all overweight and obese women have eating disorders, but some binge-eat and may gain excessive weight during pregnancy. Obesity is associated with an increased risk of complications during pregnancy, including gestational diabetes mellitus and preeclampsia. Higher maternal weight before pregnancy also increases the risk of late fetal death but protects against growth retardation of the fetus.
Obese women who deliver their first child are more likely to deliver a very premature infant (less than 31 weeks gestation). Women who are obese before becoming pregnant also may have difficulties during labor and childbirth, with poor perinatal and neonatal outcomes. These may include an increase in cesarean section, postpartum hemorrhage, and the delivery of a large-for-gestational age baby (LGA).
Morbidly obese women (BMI > 40 kg/m2) who do not have pregestational and gestational diabetes usually deliver LGA babies. Maternal diabetes is a known cause of LGA babies. To lessen the risk of the birth of a LGA infant, it is recommended that the mother not gain more than 25 lb during pregnancy. In contrast, poor weight gain by a morbidly obese woman during pregnancy does not appear to affect birth weight, and most babies are born at higher weights. Poor weight gain, such as less than 15 lb, may be associated with an increase risk of LBW and SGA babies to mothers who are obese but not morbidly obese.
Concerns About Fertility
Both underweight and overweight women and women with eating and exercise disorders who want to become pregnant should be encouraged to accept help for their disordered eating before becoming pregnant. It may not be possible to achieve a “cure,” but small changes in behavior can improve the outcome of pregnancy. Weight loss improves ovulation, pregnancy outcome, and hormone levels in obese women. Weight gain and decreased exercise improve ovulation, pregnancy outcome, and hormonal parameters in underweight women. Normalizing eating and exercise behavior in the normal-weight woman also improves fertility.
Assisted conception may not be necessary if the woman and her partner consent to treatment of the eating disorder. If, however, they feel that recovery from the eating disorder will take too long or may fail, they can be reassured that assisted conception, although expensive and uncomfortable, is usually successful. Treatment with gonadotrophin-stimulating hormone, in-vitro fertilization, or one of the newer technologies will usually result in a pregnancy. Unfortunately, these methods also increase the risk of miscarriage.
Follow-up After Birth Should Last 12 Months
The woman who has a history of disordered eating or an active eating disorder before or during pregnancy needs regular assessment of her mood, her disordered eating, and her infant-feeding practices for at least 12 months after the birth of each child. Most women with a history of mildly disordered eating will respond well to motherhood. A few neglect their children while they are binge eating and purging, and others deprive their infants of food or overfeed them. Occasionally, an anorexic mother with severely disordered eating may deprive her child of adequate food because of the fear that the child will become fat; this is the so-called “Munchausen by proxy”syndrome. Occasionally, growth retardation occurs, and the child will need to be placed out of the home after a court order is obtained. These mothers may suffer labile or depressed moods. It is impossible to predict whether a woman with a history of disordered eating and exercise will be free from her problem during future pregnancies, or whether she will have an exacerbation or relapse. One woman can respond in different ways during and after each pregnancy.
Breast-feeding: On Its Way Back
In Australia, the infant-feeding practices for women with eating disorders have changed. Originally, women with a history of eating disorders were less likely to breast-feed, as they believed it would change their body shape and lead to saggy breasts. Currently women believe they will lose body weight quicker after their pregnancy if they breast-feed, and so most women who are conscious of their body weight and shape do breast-feed their infants.
Some women find it hard to adjust to ‘normal eating’ after becoming accustomed to their increased food intake during breast-feeding. They need to be given permission to cease breast-feeding if they are not coping well because of fatigue and/or feeling down in mood. Even after 6 to 18 months of infrequent on-demand feeding, women feel their mood improves immediately after they stop breast-feeding and that they are less fatigued and more interested in sex. Women may also associate the progesterone-only ‘pill’ taken for contraception between pregnancies with a depressed mood.
Long-term Effects on the Child
There is accumulating evidence to suggest the uterine environment in which the baby develops and grows may be associated with his or her quality of life as an adult. This environment is influenced by maternal psychosocial factors. The uterine environment associated with the birth of an LGA infant may predispose this infant, if she is female, to breast cancer as an adult. There is an increased risk of cognitive disorders in intrauterine growth-retarded infants born to mothers of low body weight, and LBW babies may have a greater frequency of cardiovascular disease when they reach adulthood.
Thus, intervening to provide counseling and dietetic, psychological, and medical support during pregnancy can have lasting effects upon women with disordered eating and upon their infants.
Abraham SF, King W, and Llewellyn-Jones D. Attitudes toward body weight, weight gain and eating behavior in pregnancy. J Psychosom Obstet Gynecol 15:1998-195, 1994.
Abraham SF and Llewellyn-Jones D. Eating Disorders, the Facts, 4th ed. New York: Oxford University Press, 1997.
Abraham SF. Sexuality and reproduction in bulimia nervosa patients over 10 years. J Psychosom Res 44:491, 1998.
Abraham SF, Mira M, and Llewellyn-Jones D. Should ovulation be induced in women recovering from an eating disorder or who are compulsive exercisers? Fertil Steril 53: 566, 1990.
Bianco AT, Smilen SW, Davis Y et al. Pregnancy outcome and weight gain recommendations for the morbidly obese woman. Obstet Gynecol 91: 97, 1998.
Clark AM, Ledger W, Galletly C et al. Weight loss results in significant improvement in pregnancy and ovulation rates in anovulatory obese women. Hum Reprod 10: 2205, 1995.
Cnattingius S, Bergstrom, R, Lipworth L, and Kramer MS. Prepregnancy weight and the risk of adverse pregnancy outcomes. New Engl J Med 338: 147, 1998.
Conti J, Abraham SF and Taylor A. Eating behavior and pregnancy outcome. J Psychosom Res 44:465, 1998.
Kok JH, Lya den Ouden A, Verloove-Vanhorick SP, and Brand R. Outcome of very preterm small for gestational age infants: the first nine years of life. Brit J Obstet Gynecol, 105: 162, 1998.
Michels K, Trichopoulos D, Robins JM, et al. Birthweight as a risk factor for breast cancer. Lancet 348: 1542, 1996.
Rich-Edwards JW, Stampfer MJ, Manson JE, et al. Birth weight and risk of cardiovascular disease in a cohort of women followed up since 1976. BMJ 315: 396-403, 1997.