Background Pregnancy complicating pulmonary arterial hypertension(PAH) is a life-threatening obstetrical complication. Few studies have reported the clinical characteristics and outcomes of pregnant women with PAH. Methods Retrospectively analysis was conducted on 86 cases of pregnant women with PAH at the Department of Obstetric in Guangdong General Hospital between 2009 and 2014. Data included patients’ age, the etiologies of PAH, clinical classification of the New York Heart Association(NYHA),gestational weeks, delivery mode, maternal and fetal outcomes. Results 1There were 2 cases of idiopathic pulmonary arterial hypertension(IPAH) and 84 cases of secondary pulmonary arterial hypertension. The latter was composed by 40(47.61%) cases of congenital heart disease(CHD), 38(45.23%) cases of rheumatic heart disease(RHD), 3(3.57%) cases of systemic lupus erythematosus(SLE) and 1(1.19%) case of partial hydatidiform mole. The number of patients classified in NYHA I~IV were 8(9.30%), 41(47.67%), 26(30.23%) and 11(12.7%), respectively. And the mortality was 3.48%(3 / 86). 2Among the 86 patients, 31(36.04%) women gave birth at term and 36(41.86%) had premature delivery. In addition, 16(18.6%) women had an abortion less than 28 weeks. There were a total of 65(75.58%) live births, 61(93.84%) of whom were delivered via cesarean section, while the other 4(6.15%) were vaginal deliveries. 3 Patients were divided into3 groups, 12 of mild( < 40 mm Hg), 35 of moderate(40~70 mm Hg) and 39 of severe(≥70 mm Hg)regarding the pulmonary artery systolic pressure(s PAP) measured by ultrasound. We defined the former two as group A and the latter as group B. The significance was seen statistically in gestational weeks(32.86 ± 8.86 g vs 28.76 ± 9.84), the rate of transferring to ICU(19.14% vs 53.84%), neonatal birth-weight(2725.69 ± 467.43 vs 2044.82 ± 665.75 g), APGAR scoring(9.97 ± 0.16 vs 8.68 ± 2.08), maternal status of heart function and adverse pregnant outcomes, when compared group A with B. All the P-values mentioned above were less than0.05. Conclusions The rate of various pregnant outcomes increases gradually with the severity of the pulmonary arterial hypertension. Cesarean section may be an appropriate delivery mode and active surveillance that contributes to the improvement of pregnant outcomes. Background Pregnancy complicating pulmonary arterial hypertension (PAH) is a life-threatening obstetrical complication. Few studies have reported the clinical characteristics and outcomes of pregnant women with PAH. Methods Retrospectively analysis was conducted on 86 cases of pregnant women with PAH at the Department of Obstetric in Guangdong General Hospital between 2009 and 2014. Data included patients’ age, the etiologies of PAH, clinical classification of the New York Heart Association (NYHA), gestational weeks, delivery mode, maternal and fetal outcomes. Results 1 Everyone 2 cases of idiopathic The latter was composed of 40 (47.61%) cases of congenital heart disease (CHD), 38 (45.23%) cases of rheumatic heart disease (RHD), 3 ( 3.57%) cases of systemic lupus erythematosus (SLE) and 1 (1.19%) case of partial hydatidiform mole. The number of patients classified in NYHA I ~ IV were 8 (9.30%), 41 And the mortality was 3.48% (3/86). 2Among the 86 patients, 31 (36.04%) women gave birth at term and 36 (41.86% There were a total of 65 (75.58%) live births, 61 (93.84%) of whom were delivered via cesarean section, while the 3 patients were divided into 3 groups, 12 of mild (<40 mm Hg), 35 of moderate (40-70 mm Hg) and 39 of severe (≥ 70 mm Hg) regarding the pulmonary We defined the former two as group A and the latter as group B. The significance was seen statistically in gestational weeks (32.86 ± 8.86 g vs 28.76 ± 9.84), the rate of transferring to ICU (19.14% vs 53.84%), neonatal birth-weight (2725.69 ± 467.43 vs 2044.82 ± 665.75 g), APGAR scoring (9.97 ± 0.16 vs 8.68 ± 2.08), maternal status of heart function and adverse pregnant outcomes, when compared gr oup A with B. All the P-values ​​mentioned above were less than 0.05. Conclusions The rate of various pregnant outcomes were gradually with the severity of the pulmonary arterial hypertension. Cesarean section may be an appropriate delivery mode and active surveillance that contributes to the improvement of pregnant outcomes.