Endocrine Abstracts

Metformin therapy induces weight loss and improves insulin resistance in women with PCOS. In pregnancy, gestational diabetes mellitus (GDM) is more prevalent in women with PCOS and overweight compared to women without PCOS. Disappointingly, GDM incidence was similar in women with PCOS treated with metformin or placebo, initiated late in 1st trimester. Furthermore, no significant longterm beneficial effect was seen in metabolic health of women treated with metformin versus placebo. Pregnancy is a window of sensitivity in offspring, and metformin may pose a risk, metformin passes placenta and maternal metformin intake results in therapeutic metformin concentrations in umbilical cord blood, hence metformin exposure of offspring is quite high. However, metformin therapy had potentially beneficial, lowering effect on maternal testosterone, in women with PCOS carrying a boy. Testosterone is elevated during healthy pregnancy, but women with PCOS have significantly higher testosterone levels than women without PCOS. Moreover, boys have been reported more susceptible to maternal testosterone regarding risk of neurodevelopmental disorders, autism spectrum disorder, but there is no data on maternal metformin treatment and autism spectrum disorder in PCOS. However, available data regarding metformin and neurodevelopment are not fully reassuring, as metformin therapy in pregnancy may be linked to borderline reduced cognitive function in children. Overall, metformin therapy cannot be recommended for pregnant women with PCOS due to lack of effect and offspring safety concerns, supporting previous guidelines.

Disclosure of interest: None declared