How Pre-Pregnancy Weight and Polycystic Ovary Syndrome Impact Pregnancy Outcomes: A Population-Based Cohort Study

Pre-pregnancy overweight/obese status among women with polycystic ovary syndrome (PCOS) could increase the risk of at least one adverse pregnancy outcome (APO). This study aimed to determine how pre-pregnancy weight and PCOS impact pregnancy outcomes.

For the current study, we used data collected in the Tehran Lipid and Glucose Study (TLGS), a cohort study with an average of 23 years of follow-up, including 1105 women. The incidences of APOs, including gestational diabetes (GDM), preeclampsia (PE), and preterm birth, were compared between groups with different categories of pre-pregnancy body mass index (18-24.9, 25-29.9, ≥ 30 kg/m²), PCOS, and non-PCOS groups. The risk ratio (RR) and 95% confidence interval (95% CI) were estimated using the generalized linear models after adjusting for confounding factors. The participants included 864 non-PCOS women and 241 women with PCOS.

Findings showed that the incidence rate of at least one APO among women with PCOS compared with non-PCOS group was not significant (32.4% vs. 26.4%, p > 0.05). Obese women with PCOS (RR: 2.01; 95% CI: 1.11-3.62) and non-PCOS (1.75; 1.10-2.79) were at increased risk of GDM compared to non-PCOS normal weight women. Also, obese women with PCOS were at increased risk of PE (1.80; 1.08-2.97) compared to the non-PCOS normal weight women. Overweight and obese women with PCOS were at increased risk of at least one APO (1.57; 1.06-2.32) and (1.44; 1.03-2.02), respectively.

The study found that women with PCOS with pre-pregnancy overweight/obese status are at increased risk of at least one APO and GDM. Management of pre-pregnancy weight should be promoted in women with PCOS.