Women with polycystic ovary syndrome (PCOS) face breastfeeding challenges. We aimed to compare exclusive breastfeeding rates in women with PCOS to those in a population-based cohort, and to explore the effect of metformin and metabolic factors on exclusive breastfeeding in women with PCOS. This cohort study included 653 women from the pilot, PregMet, and PregMet2 randomized trials on metformin in pregnant women with PCOS (2000–2017), and 63,927 women from the Norwegian Mother, Father and Child Cohort Study (MoBa) (1999–2008) as the reference group. Logistic regression estimated odds ratios for exclusive breastfeeding one month postpartum in women with PCOS versus MoBa women, and in women with PCOS randomized to metformin or placebo. Women with PCOS reported less exclusive breastfeeding than MoBa women one month postpartum (adjusted OR (aOR) 0.52 (0.42–0.63)). Among women of normal weight, those with PCOS breastfed to the same extent as MoBa women (aOR 0.98 (0.63–1.54)), but less in the overweight or obesity categories (aOR 0.56 (0.39–0.82) and aOR 0.55 (0.40–0.76), respectively). However, differences across weight categories were not statistically significant (p-value for interaction = 0.088). We found no difference in exclusive breastfeeding between metformin and placebo-treated women with PCOS. Hypertensive disorders and gestational diabetes did not affect exclusive breastfeeding rate in PCOS. Exclusive breastfeeding did not differ between normal weight women with PCOS and women from the MoBa study. Among women with high BMI, women with PCOS breastfed less exclusively than MoBa women. In PCOS, neither metformin treatment, hypertension nor gestational diabetes affected exclusive breastfeeding.
Husby et al. (Sat,) studied this question.