Context: Polycystic ovary syndrome (PCOS) is one of the most common endocrine and metabolic disorders of women in their reproductive lifespan. It is reported that the disease can increase the risk of pregnancy complications such as miscarriage, multiple pregnancy, gestational diabetes and gestational hypertension, which can impact on patients themselves and their offspring directly. Objective:To analyze the risk of pregnancy complications for polycystic ovary syndrome. Methods:We analyzed the incidence rates of gestational diabetes, gestational hypertension disease, premature labor, cesarean delivery, low birth weight and macrosomia of pregnant patients. Then we compared them with the incidence rates of healthy people. Patients: Patients diagnosed with polycystic ovary syndrome in reproductive endocrinology department, west China hospital during November 2011 to November 2016. Patients were included in this study cohort when they were pregnant. Interventions: We followed with this patients by phone or social software. Main Outcome Measures:We calculate the relative risk of the pregnancy complications. Results: 142 patients were included in the study, the incidence rates of miscarriage, gestational hypertension diseases, gestational diabetes, premature birth rate, low birth weight, macrosomia and the cesarean delivery rate are 14.5% (24/142), 5.6% (8/142), 22.5% (32/142), 8.5% (12/142), 5.6% (8/142), 4.2% (6/142) and 58.5% (83/142) respectively. As for the healthy pregnant women, the incidence rates are 5.0%(IR=2.90), 29.8%(IR=0.19), 16.7%(IR=1.35), 2.2%(IR=3.79), 2.6%(IR=2.13), 4.0%(IR=1.07) and 34.3%(IR=1.70) respectively. Conclusions: During pregnancy, patients with polycystic ovary syndrome have higher risk of abortion, gestational diabetes, premature birth, low birth weight and cesarean section. The management of polycystic ovary syndrome during pregnancy need to be more intensive.