To analyze the pregnancy complications and outcomes in adolescent women in minority areas in China and the factors affecting the pregnancy outcomes.

This retrospective study enrolled 697 singleton pregnant women who were younger than 20 years old and delivered at Sanjiang Dong Autonomous County People's Hospital of Liuzhou City from January 1, 2014, to December 31, 2018, as the case group. Meanwhile, 2 592 cases aged between 20 to 25 years and delivered during the same period were selected as the control group in an allocation ratio of 1∶4. Chi-square test, t test and binary logistic regression were used for comparing the differences of general characteristics, pregnancy complications, comorbidities and pregnancy outcomes between the two groups.

(1) The body mass index before delivery of the case group was lower than that of the control group [(24.7±3.4) vs (25.1±3.1) kg/m², t=－2.062, P=0.039]. The proportion of Dong minority was accounted for 48.06%(335/697) in the case group and 52.04%(1 349/2 592) in the control group. The proportion of women with junior school education or lower was higher in the case group than that in the control group [95.41% (665/697) vs 90.27% (2 340/2 592), χ²=45.086, P<0.001]. (2) The case group was noted for higher incidence of anemia [24.25% (169/697) vs 15.20% (394/2 592),χ²=31.683], premature delivery [7.17% (50/697) vs 4.55% (118/2 592), χ²=7.786], premature rupture of membranes [13.34% (93/697) vs 9.10% (237/2 592), χ²=10.731] and oligohydramnios [9.76% (68/697) vs 7.02% (182/2 592), χ²=5.848] than the control group (all P<0.05). (3) The incidence of cesarean section [27.26% (190/697) vs 38.04% (986/2 592),χ²=27.791, P<0.001] and the neonatal birth weight [(3 047.29±453.46) vs (3 131.01±472.44) g,t=－4.188, P<0.001] in the case group were lower, but the incidence of episiotomy [40.17% (280/697) vs 8.72% (226/2 592)] and the proportion of neonatal intensive care unit admission[10.76% (75/697) vs 3.82% (99/2 592)] were higher when comparing to the control group (χ²=417.439 and 52.816, both P<0.001). (4) Multivariate binary logistic regression analysis showed that the risk of cesarean section (aOR=0.62, 95%CI: 0.51-0.75) was reduced in adolescent women, but the risks of episiotomy (aOR=6.20, 95%CI: 4.99-7.71) and neonatal intensive care unit admission (aOR=2.68, 95%CI: 1.92-3.75) increased.

Most of the pregnant adolescents are less-educated and ethnic minorities in this study, among which the Dong minority was predominant. Adolescent pregnancies are at a higher risk of anemia, preterm birth and premature rupture of membranes. Therefore, enhanced perinatal management of adolescent pregnancy is recommended to reduce adverse pregnancy outcome.

Pregnancy in adolescence; Pregnancy outcome; Minority groups