Zhang B Y, Li S S, Shang S H, Li M M, Li S R, Mi B B, Yan H, Dang S N
Department of Epidemiology and Biostatistics, School of Public Health, Xi'an Jiaotong University Health Science Center, Xi'an 710061, China.
Department of the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China.
Zhonghua Liu Xing Bing Xue Za Zhi. 2019 Jul 10;40(7):786-790. doi: 10.3760/cma.j.issn.0254-6450.2019.07.010.
To investigate the interaction of pregnancy-induced hypertension and history of preterm birth on the risk of small for gestational age. Stratified multistage random sampling method was used to choose samples from 30 districts and counties of Shaanxi province. Information on childbearing-age women with their children between January 2010 and November 2013 was retrospectively collected through face-to-face questionnaire survey. The childbearing-aged women were in pregnancy or having had definite outcomes of pregnancy. Enumeration data were described by percentage, and measurement data were described by Mean±SD, and (2) test was used to compare the rates. Unconditional logistic regression analysis was performed to estimate the interaction between pregnancy-induced hypertension and history of preterm birth on the risk of small for gestational age, and by using small for gestational age as dependent variables, pregnancy-induced hypertension and history of preterm birth as independent variables. Confounding factors were under control. Firstly, the association between pregnancy-induced hypertension and small for gestational age has been analyzed in primiparas, secondly, interaction of pregnancy-induced hypertension and history of preterm birth on the risk of small for gestational age has been analyzed in multiparas. A total of 25 751 women of childbearing age and their children were recruited. 60.55 (15 592/25 751) were primiparas, 39.45 (10 159/25 751) were multiparas, the rate of history of preterm birth was 1.89 (192/10 159) for multiparas. The incidence rates of pregnancy-induced hypertension and small for gestational age were 1.55 and 15.49 in pregnant woman (400/25 751) and their newborns (3 990/25 751). Unconditioned logistic regression analysis showed that compared with woman without pregnancy-induced hypertension, primiparas with pregnancy-induced hypertension had increased risk of small for gestational age (=1.43, 95: 1.02-2.00, =0.041). Regarding multiparas, the main effect of pregnancy-induced hypertension had a positive correlation with small for gestational age (=1.34, 95: 0.91-1.96), but there was no statistical significance (=0.138). The main effect of history of preterm birth was positively correlated with small for gestational age (=1.61, 95: 1.13-2.31, =0.009). The interaction term "pregnancy-induced hypertension×history of preterm birth" was positively associated with risk of small for gestational age (=5.93, 95: 1.19-29.61, =0.030). Pregnancy-induced hypertension was associated with increased risk for small for gestational age in both primiparas and multiparas, and history of preterm birth further increased risk for small for gestational age in pregnant women with pregnancy-induced hypertension, indicating that there was multiplication interaction between pregnancy-induced hypertension and history of preterm birth.
为研究妊娠期高血压与早产史对小于胎龄儿风险的相互作用。采用分层多阶段随机抽样方法从陕西省30个区县选取样本。通过面对面问卷调查回顾性收集2010年1月至2013年11月育龄妇女及其子女的信息。这些育龄妇女处于孕期或有明确的妊娠结局。计数资料用百分比描述，计量资料用均数±标准差描述，采用χ²检验比较率。进行非条件logistic回归分析，以评估妊娠期高血压与早产史对小于胎龄儿风险的相互作用，将小于胎龄儿作为因变量，妊娠期高血压和早产史作为自变量，控制混杂因素。首先，在初产妇中分析妊娠期高血压与小于胎龄儿的关联，其次，在经产妇中分析妊娠期高血压与早产史对小于胎龄儿风险的相互作用。共招募了25751名育龄妇女及其子女。60.55%（15592/25751）为初产妇，39.45%（10159/25751）为经产妇，经产妇的早产史发生率为1.89%（192/10159）。孕妇（400/25751）及其新生儿（3990/25751）的妊娠期高血压和小于胎龄儿的发生率分别为1.55%和15.49%。非条件logistic回归分析显示，与无妊娠期高血压的妇女相比，患有妊娠期高血压的初产妇发生小于胎龄儿的风险增加（OR = 1.43，95%CI：1.02 - 2.00，P = 0.041）。对于经产妇，妊娠期高血压的主效应与小于胎龄儿呈正相关（OR = 1.34，95%CI：0.91 - 1.96），但无统计学意义（P = 0.138）。早产史的主效应与小于胎龄儿呈正相关（OR = 1.61，95%CI：1.13 - 2.31，P = 0.009）。交互项“妊娠期高血压×早产史”与小于胎龄儿风险呈正相关（OR = 5.93，95%CI：1.19 - 29.61，P = 0.030）。妊娠期高血压在初产妇和经产妇中均与小于胎龄儿风险增加相关，早产史进一步增加了患有妊娠期高血压孕妇的小于胎龄儿风险，表明妊娠期高血压与早产史之间存在相乘交互作用。
