Klebanoff M A
Epidemiology Branch, National Institutes of Child Health and Human Development, Bethesda, MD 20892.
Am J Public Health. 1988 Jun;78(6):667-70. doi: 10.2105/ajph.78.6.667.
The effect of interpregnancy interval on the birthweight of the subsequent child was investigated in a cohort of 5,938 women who registered for two consecutive pregnancies in the Collaborative Perinatal Project. Mean birthweight increased from 3,101 grams for intervals of less than 3 months to 3,193 grams for intervals of 15-17.9 months and remained stable thereafter (p for trend = 0.006). However, women with shorter intervals were younger, lighter weight, and less educated at the beginning of the first pregnancy than were women with longer intervals; the birthweight of their previous child was lower, and they were of marginally lower socioeconomic status. Adjustment for confounders reduced the maximum difference in mean birthweight by interval length from 92 to 39 grams, and blunted the trend for lower birthweights with shorter intervals (p = 0.45). Similarly, adjustment reduced the increased risk of low birthweight among women with the shortest intervals from 52 per cent to 12 per cent. We conclude that a short interpregnancy interval is primarily a marker for a woman who is otherwise at high risk, and that modification of this interval alone may be unlikely to have a major impact on low birthweight.
在协作围产期项目中，对5938名连续登记两次怀孕的女性队列进行研究，以调查妊娠间隔对下一胎出生体重的影响。平均出生体重从间隔小于3个月时的3101克，增加到间隔15至17.9个月时的3193克，此后保持稳定（趋势p值=0.006）。然而，间隔较短的女性在首次怀孕开始时，比间隔较长的女性更年轻、体重更轻、受教育程度更低；她们前一胎的出生体重更低，社会经济地位也略低。对混杂因素进行调整后，平均出生体重因间隔长度产生的最大差异从92克降至39克，并减弱了间隔较短时出生体重较低的趋势（p=0.45）。同样，调整后将间隔最短的女性中低出生体重的增加风险从52%降至12%。我们得出结论，妊娠间隔短主要是其他方面处于高风险女性的一个标志，仅改变这一间隔不太可能对低出生体重产生重大影响。
