Maternal and Child Health Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh.
Department of Women's and Children's Health, Uppsala Universitet, Uppsala, Sweden.
BMJ Glob Health. 2023 Nov;8(11). doi: 10.1136/bmjgh-2023-012521.
A history of preterm birth reportedly increases the risk of subsequent preterm birth. This association has primarily been studied in high-income countries and not in low-income settings in transition with rapidly descending preterm birth figures. We evaluated the population-based trends of preterm births and recurrent preterm births and the risk of preterm birth recurrence in the second pregnancy based on prospectively studied pregnancy cohorts over three decades in Matlab, Bangladesh.
A population-based cohort included 72 160 live births from 1990 to 2019. We calculated preterm birth and recurrent preterm birth trends. We assessed the odds of preterm birth recurrence based on a subsample of 14 567 women with live-born singletons in their first and second pregnancies. We used logistic regression and presented the associations by OR with a 95% CI.
The proportion of preterm births decreased from 25% in 1990 to 13% in 2019. The recurrent preterm births had a similar, falling pattern from 7.4% to 3.1% across the same period, contributing 27% of the total number of preterm births in the population. The odds of second pregnancy preterm birth were doubled (OR 2.18; 95% CI 1.96 to 2.43) in women with preterm birth compared with the women with term birth in their first pregnancies, remaining similar over the study period. The lower the gestational age at the first birth, the higher the odds of preterm birth in the subsequent pregnancy (test for trend p<0.001).
In this rural Bangladeshi setting, recurrent preterm births contributed a sizeable proportion of the total number of preterm births at the population level. The increased risk of recurrence remained similar across three decades when the total proportion of preterm births was reduced from 25% to 13%.
据报道，早产史会增加随后早产的风险。这种关联主要在高收入国家进行了研究，而在低收入转型国家中，这种关联尚未得到研究，这些国家的早产率正在迅速下降。我们评估了基于队列的孟加拉国 Matlab 地区 30 多年来的早产和复发性早产的人群趋势，以及第二胎早产复发的风险。
一个基于人群的队列包括 1990 年至 2019 年的 72160 例活产。我们计算了早产和复发性早产的趋势。我们评估了 14567 名在第一和第二胎中生育活产单胎的女性亚组中早产复发的可能性。我们使用逻辑回归，并以 OR 及其 95%CI 表示关联。
早产的比例从 1990 年的 25%下降到 2019 年的 13%。复发性早产也呈现出类似的下降趋势，从 1990 年的 7.4%下降到 2019 年的 3.1%，占同期总早产人数的 27%。与第一胎足月分娩的女性相比，第一胎早产的女性第二胎早产的可能性增加了一倍（OR 2.18；95%CI 1.96 至 2.43），在整个研究期间保持不变。第一胎的分娩孕周越低，随后妊娠早产的可能性越高（趋势检验 p<0.001）。
在这个孟加拉农村地区，复发性早产在人群水平上占总早产人数的相当大比例。当总早产率从 25%降至 13%时，复发的风险增加仍然相似。
