Polycystic ovarian syndrome (PCOS) is the most common reproductive disorder in women of childbearing age and is also associated with metabolic abnormalities including obesity, type 2 diabetes, dyslipidemia, etc. Importantly, a number of adverse outcome are seen in pregnancies complicated by PCOS, including gestational diabetes mellitus (GDM), preeclampsia and miscarriage. However, optimal management of PCOS complicated pregnancy is not known. This study seeks to explore whether healthy lifestyle intervention in overweight/obese pregnant women with PCOS could reduce gestational weight gain (GWG) and incidence of GDM.

A randomized controlled trial in PCOS pregnant women will be initiated at 8-12 weeks of gestation util delivery. Participants will be randomly assigned to the control group (standard care) or the intervention group (intensive lifestyle intervention). The intervention will focus on restricting energy intake combined with behavioral lifestyle modification through participation in group sessions and individual counseling. The primary outcome will be GWG and secondary outcome will be the incidence of GDM.

Our hypothesis is that intensive lifestyle intervention in overweight/obese pregnant women with PCOS will decrease GWG and reduce the incidence of GDM.

Inclusion Criteria:

• gestational age between 8 and 12 weeks of gestation, pre-pregnancy BMI≥25 (kg/m2)
• age ≥18 years, and a singleton pregnancy.

Exclusion Criteria:

• patients with prediabetes and diabetes, hypertension, chronic renal disease, thyroid disorder
• gestational weeks ≥ 13
• age <18 years
• multiple pregnancy
• uterine malformation
• or physical restriction that prevents exercise.