Khoshnood B, Lee K S, Wall S, Hsieh H L, Mittendorf R
Department of Pediatrics, University of Chicago Children's Hospital, IL 60637, USA.
Am J Epidemiol. 1998 Oct 15;148(8):798-805. doi: 10.1093/oxfordjournals.aje.a009701.
The authors studied the effects and population-level impact of short (< or = 12 months) interpregnancy intervals on the risks for low (<2.5 kg) birth weight and preterm (<37 weeks) delivery of liveborn singleton infants to US African American, Mexican, Native American, non-Hispanic white, and Puerto Rican mothers (n = 4,841,418) from 1989 to 1991. Statistical analyses were done by using the Mantel-Haenszel correlation statistic chi-square test and logistic regression. The proportion of livebirths associated with < or =12-month interpregnancy intervals was the lowest among non-Hispanic whites (18.5%, 95% confidence interval 18.5-18.5) and the highest among Native Americans (29.7%, 95% confidence interval 29.2-30.2). As compared with mothers with >12-month intervals, mothers with <6-month intervals had an approximately 50% to 80% increased risk of very low (<1.5 kg) birth weight delivery and a 30% to 90% increased risk of very preterm (<32 weeks) delivery. Logistic regression analyses showed that the adverse effects of short intervals were reduced by about 10% but remained for the most part significant after controlling for potential confounding by maternal age, education, parity, marital status, prenatal care, smoking, and previous preterm delivery.
作者研究了短（≤12个月）的妊娠间隔对1989年至1991年期间美国非裔美国人、墨西哥人、美洲原住民、非西班牙裔白人及波多黎各裔母亲所生单胎活产婴儿低出生体重（<2.5kg）和早产（<37周）风险的影响及人群水平的影响（n = 4,841,418）。采用Mantel-Haenszel相关统计量卡方检验和逻辑回归进行统计分析。非西班牙裔白人中妊娠间隔≤12个月的活产比例最低（18.5%，95%置信区间18.5 - 18.5），美洲原住民中最高（29.7%，95%置信区间29.2 - 30.2）。与妊娠间隔>12个月的母亲相比，妊娠间隔<6个月的母亲极低出生体重（<1.5kg）分娩风险增加约50%至80%，极早产（<32周）分娩风险增加30%至90%。逻辑回归分析显示，在控制了母亲年龄、教育程度、产次、婚姻状况、产前护理、吸烟及既往早产等潜在混杂因素后，短间隔的不良影响降低了约10%，但在很大程度上仍具有显著性。
