Salihu Hamisu M, Chatman Leia M, Alio Amina P, Aliyu Muktar H, Kirby Russell S, Alexander Greg R
Department of Maternal and Child Health, University of Alabama at Birmingham, 1665 University Blvd, Room 320, Birmingham, AL 35294, USA.
J Natl Med Assoc. 2004 Dec;96(12):1618-25.
We investigated whether an association existed between single motherhood and neonatal mortality among twins and whether such a linkage varied by race.
Retrospective cohort analysis on 446,570 twin live births (between 24-44 gestational weeks inclusive) in the United States from 1995 through 1998. Neonatal survival was compared between twins of single and those of married mothers for blacks and whites separately using Cox proportional hazards regression that adjusted for the confounding effects of education, parity, adequacy of prenatal care and maternal smoking during pregnancy. The Robust Sandwich Estimator was employed to adjust for intracluster correlation.
The rates for neonatal mortality among blacks were 34.9 per 1,000 among married and 43.4 per 1,000 among single mothers. Among whites, the rates were 20.6 per 1,000 for married and 28.9 per 1,000 for unmarried mothers. Neonatal mortality was significantly elevated among white twins of single mothers (Hazard Ratio (HR) = 1.23; 95% Confidence Interval (CI) = 1.14-1.31) and among black twins of single mothers (HR = 1.12; 95% CI = 1.01-1.25). However, when gestational age was adjusted for, the association between single motherhood and neonatal mortality disappeared.
Single motherhood was a risk factor for neonatal mortality among twins, and the disparity in survival was more accentuated among whites. The association between single motherhood and neonatal mortality was explained by the preponderance of preterm births among twins of unmarried gravidas. Our findings reinforce the importance of future research to develop and test interventions that will decrease the incidence of preterm birth.
我们研究了双胞胎中单亲母亲身份与新生儿死亡率之间是否存在关联，以及这种联系是否因种族而异。
对1995年至1998年美国446,570例双胞胎活产（孕龄在24至44周之间，含24周和44周）进行回顾性队列分析。使用Cox比例风险回归分别比较黑人和白人中单亲母亲与已婚母亲所生双胞胎的新生儿存活率，该回归对教育程度、产次、产前护理充足程度以及孕期母亲吸烟等混杂因素的影响进行了调整。采用稳健三明治估计量来调整聚类内相关性。
黑人中，已婚母亲所生双胞胎的新生儿死亡率为每1000例中有34.9例，单亲母亲所生双胞胎的新生儿死亡率为每1000例中有43.4例。白人中，已婚母亲所生双胞胎的新生儿死亡率为每1000例中有20.6例，未婚母亲所生双胞胎的新生儿死亡率为每1000例中有28.9例。单亲母亲所生白人双胞胎的新生儿死亡率显著升高（风险比（HR）=1.23；95%置信区间（CI）=1.14 - 1.31），单亲母亲所生黑人双胞胎的新生儿死亡率也显著升高（HR = 1.12；95% CI = 1.01 - 1.25）。然而，在对孕龄进行调整后，单亲母亲身份与新生儿死亡率之间的关联消失了。
单亲母亲身份是双胞胎新生儿死亡的一个风险因素，且白人中存活率的差异更为明显。未婚孕妇所生双胞胎中早产占优势解释了单亲母亲身份与新生儿死亡率之间的关联。我们的研究结果强化了未来开展研究以开发和测试能降低早产发生率的干预措施的重要性。
