BMI not associated with FET outcomes in patients with PCOS

Takeaway

• BMI is not significantly associated with pregnancy or perinatal outcomes in patients with polycystic ovary syndrome (PCOS) undergoing frozen embryo transfer (FET).

Why this matters

• The effects of BMI on pregnancy outcomes in women with PCOS undergoing FET were unclear.

Key results

• BMI ≥30 kg/m² ("obese") and BMI 18.5-24.9 kg/m² ("normal") were associated with similar odds of clinical pregnancy (OR, 0.47; 95% CI, 0.05-3.57), miscarriage (OR, 1.33; 95% CI, 0.88-1.98), ongoing pregnancy (OR, 0.96; 95% CI, 0.53-1.72), live birth (OR, 0.62; 95% CI, 0.18-2.49), delivery <37 weeks of gestation (OR, 0.93; 95% CI, 0.57-1.53), delivery <32 weeks of gestation (OR, 0.81; 95% CI, 0.33-2.04), birth weight <2500 g (OR, 0.67; 95% CI, 0.22-1.96), and birth weight <1500 g (OR, 1.08; 95% CI, 0.84-1.36).
• Similar results were observed for BMI 25-29.9 kg/m² ("overweight") vs BMI 18.5-24.9 kg/m².

Study design

• 1680 women with PCOS undergoing FET were stratified by BMI (972 normal, 480 overweight, 228 obese) and analysed for pregnancy and perinatal outcomes.
• Funding: National Natural Science Foundation of China; National Key Research and Development Program of China.

Limitations

• Retrospective study.