Kallan J E
Soc Biol. 1997 Fall-Winter;44(3-4):205-12.
This study examines the net effects of the interpregnancy interval (time period from one birth to the next pregnancy) on the risks of preterm birth, intrauterine growth retardation, and infant mortality, for blacks and whites separately, using data from 1991 U.S. Linked Birth-Infant Death files. Results show that short (less than 7 months) and long (61+ months) intervals between pregnancies raise the risk of preterm birth and intrauterine growth retardation for both race groups, though the increase in risk is generally less than 30 per cent. Short intervals also raise (slightly) the risk of infant mortality after controlling for birthweight and gestational age.
本研究利用1991年美国出生与婴儿死亡关联档案中的数据，分别考察了黑人与白人两次妊娠间隔时间（从一次分娩到下次怀孕的时间段）对早产、胎儿宫内发育迟缓及婴儿死亡风险的净影响。结果显示，两次妊娠间隔时间较短（少于7个月）及较长（61个月及以上）均会增加两个种族早产和胎儿宫内发育迟缓的风险，不过风险增加幅度一般小于30%。在对出生体重和孕周进行控制后，较短的妊娠间隔也会（轻微）增加婴儿死亡风险。
