Anorexia nervosa during pregnancy associated with several adverse neonatal outcomes

According to a recent study published in the American Journal of Obstetrics and Gynecology, by providing treatment for anorexia nervosa both before and during pregnancy and by offering guidance on healthy weight gain during pregnancy, the likelihood of successful live births among these patients may be improved.

This study investigated the association between adverse live-born pregnancy outcomes and anorexia nervosa while accounting for confounding factors using adjustment modelling. The study analyzed data from California live-born singletons born between 2007 and 2021, using administrative data sets linked to hospital discharge records. Anorexia nervosa diagnosis was obtained from International Classification of Diseases codes. Adverse pregnancy outcomes were examined. The study used Poisson regression models. The final adjusted model included demographics, anxiety, depression, smoking and substance use.

Key findings of this investigation are:

• The sample had 241 pregnant women with anorexia nervosa and 6,418,236 without an eating disorder diagnosis.
• There was an association between anorexia nervosa diagnosis during pregnancy and adverse pregnancy outcomes (unadjusted models). The relative risks ranged from 1.65 to 3.56 compared to those without an eating disorder.
• Birthing people with an anorexia nervosa diagnosis were more likely to have anemia, preterm labor and birth, oligohydramnios, severe maternal morbidity, low-birthweight infant (between 32 and 36 weeks)
• Underweight prepregnancy BMI mediated 7.78% of excess preterm births and 18% of excess small for gestational age infants.

 • Gestational weight gain below the recommendation mediated 38.89% and 40.44 % of the excess in preterm births and low-birthweight infants.

Anorexia nervosa during pregnancy was linked to several adverse outcomes, but these risks were lower when accounting for factors like anxiety, depression, substance use, and smoking. A substantial portion of the increased risk was due to low pre-pregnancy BMI and insufficient gestational weight gain, which should be considered by clinicians in treating patients with anorexia nervosa. Addressing anorexia nervosa and comorbid conditions, as well as advising patients on these mediating factors (preconception weight and gestational weight gain), may improve live-born pregnancy outcomes.

Reference:

Baer, R. J et al. Adverse live-born pregnancy outcomes among pregnant people with anorexia nervosa. American Journal of Obstetrics and Gynecology. https://doi.org/10.1016/j.ajog.2023.11.1242