Table 1.

Part of reports on the association between PCOS and complications in pregnancy.

Complications	Methods	Results	Reference
Miscarriage	A retrospective cohort study with 452 women with recurrent miscarriage and a meta-analysis were conducted.	The prevalence of PCOS in recurrent miscarriage was 9.5%.	(4)
	The study used a nationwide population-based Taiwan National Health Insurance Research Database for the period 1998-2012.	PCOS patients have a 33.5% risk of miscarriage and a 25% risk reduction with metformin treatment.	(5)
	This single-blind randomized controlled trial was conducted at Dr. Shariati Hospital and Omid Fertility Clinic in Tehran, Iran. 178 women with PCOS were included in the study.	The miscarriage rate in the control group (no intervention) was about 33.3%.	(6)
Gestational hypertension	The report studied 188 pregnant patients with PCOS treated from June 1, 2018 to November 30, 2020, assessing personal and clinical characteristics of patients with and without gestational hypertension.	The incidence of gestational hypertension in patients with PCOS was 27.66%. BMI ≥ 24 kg/m2, family history of hypertension, history of adverse pregnancy, history of contraceptive use, and family history of gestational hypertension were independent risk factors for the development of gestational hypertension in patients with PCOS, and hypertension is an independent risk factor for the development of gestational hypertension in patients with PCOS.	(7)
	A total of 30 studies eligible for meta-analysis were included.	The association between PCOS and gestational hypertension was significant (OR 2.02, 95CI% 1.83-2.22). This association remained significant after adjusting for age, BMI and infertility (OR 1.48, 95CI% 1.48-1.60).	(8)
	A diverse community cohort study screened 1765 women with PCOS in pregnancy without pre-existing hypertension.	The number of people with hypertension during pregnancy accounted for 48%.	(9)
Infertility	This is a large community-based cohort study with 9145 respondents aged 28-33 years.	72% of women with polycystic ovary syndrome had infertility, while only 16% of women without polycystic ovary syndrome were infertile.	(10)
Preterm birth	This study included 1,167 women diagnosed with PCOS using the Rotterdam criteria, underwent a frozen embryo transfer (FET).	Women with polycystic ovary syndrome have a higher chance of preterm delivery compared to women without polycystic ovary syndrome(OR1.53, 95% CI1.23-1.91).	(11)
	This study performed a clinical examination, including transvaginal ultrasound, on pregnant women who met the inclusion criteria.	Twenty-nine of 114 women (25.4%) with preterm delivery met the criteria for PCOS, while 18 of 127 women (14.2%) with full-term pregnancy met the criteria for PCOS (P = 0.03).	(12)