Considerations in managing bulimia nervosa during pregnancy
If a patient has active bulimia nervosa during pregnancy, the pregnancy is considered ‘high risk’ because of the increased risk of fetal death. Refer the patient to a specialist unit for perinatal care as soon as practical—hospitalisation is sometimes required1.
Purging and binge eating often substantially decrease during pregnancy. Some patients fear adverse outcomes from their eating disorder on the pregnancy—this can lead to a time-limited remission. Other patients may develop a recurrence or worsening of their disorder because of anxiety and a fear of loss of control provoked by the weight gain, food cravings and food aversions associated with pregnancy.
Usually people with a history of bulimia nervosa have a sufficient diet during pregnancy and do not significantly differ in their nutrient intake and dietary supplement use compared to females without an eating disorder. They are more likely to be diagnosed with iron deficiency anaemia.
Other than increased fetal mortality rates, the literature about the association between bulimia nervosa and adverse pregnancy and neonatal outcomes are mixed and inconsistent. The finding that is most often replicated is that bulimia nervosa is associated with increased rates of miscarriages. Other adverse outcomes reported include:
- increased rate of hyperemesis gravidarum (though this may be masking purging behaviours)
- increased rate of caesarean section
- more problems with episiotomy repair
- smaller head circumference of infants.
The treatment of bulimia nervosa during pregnancy follows the same principles as for a nonpregnant patient, see Principles of managing bulimia nervosa. Patients should be treated by a multidisciplinary team involving an obstetrician, psychiatrist (or a specialist eating disorder service), dietitian and physician. Depending on the patient’s baseline symptoms, weight and medical status, the patient and fetus may require more frequent monitoring than usual, using blood tests (to detect anaemia, thyroid dysfunction, electrolyte disturbance and nutritional deficiencies) and ultrasounds (to monitor fetal growth). If this is not possible, seek advice from their psychiatrist and a paediatrician.
For advice on psychotropic use during pregnancy, see here.