Faculty of Social Sciences, University of Tampere, Tampere, Finland.
Department of Information Services, Finnish Institute for Health and Welfare, Helsinki, Finland.
Acta Obstet Gynecol Scand. 2020 May;99(5):651-659. doi: 10.1111/aogs.13788. Epub 2020 Mar 3.
Previous induced abortions have been associated with adverse birth outcomes. However, only a few studies have considered the possible influence of gestational age at induced abortion. Therefore, this study aimed to identify the impacts of gestational age during prior induced abortion(s) on subsequent births among first-time mothers in Finland.
First-time mothers (n = 418 690) with singleton births between 1996 and 2013 were identified from the Finnish Medical Birth Register and linked to the Abortion Register. Logistic regression analysis was used to estimate the risk (odds ratio [OR] and 95% confidence interval [CI]) of birth outcomes such as prematurity, low birthweight, perinatal death and small for gestational age (SGA).
Higher risk was determined for extremely preterm birth (OR 2.28; 95% CI 1.53-3.39) and very low birthweight (OR 1.62; 95% CI 1.22-2.16) in women having had late-induced abortion(s) (≥12 gestational weeks) compared with women having had early-induced abortion(s) (<12 gestational weeks); after adjusting for women's background characteristics, abortion method and interval between the pregnancies. When the analysis was limited to a single abortion, an increased risk was found for extremely preterm birth (OR 1.71; 95% CI 1.02-2.81). Higher risks were found for extremely preterm (OR 4.09; 95% CI 2.05-8.18) and very low birthweight (OR 2.65; 95% CI 1.61-4.35) among women with two or more late-induced abortions compared with those with two or more early-induced abortions. Worse outcomes were seen after a late-induced abortion compared to an early-induced abortion for both medically and surgically induced abortion.
The risk of subsequent adverse birth outcomes is very small if any, but the risk is higher with increasing gestational age at the time of induced abortion. Our study supports reduction of unintended pregnancy and offering abortion services without delay and as early in gestation as possible.
先前的人工流产与不良生育结局有关。然而，只有少数研究考虑了人工流产时的孕龄可能产生的影响。因此，本研究旨在确定芬兰初次分娩的母亲中，先前人工流产时的孕龄对后续分娩的影响。
1996 年至 2013 年间，从芬兰医疗出生登记处和堕胎登记处确定了 418690 名单胎分娩的初次分娩母亲，并进行了逻辑回归分析，以估计早产、低出生体重、围产儿死亡和小于胎龄儿（SGA）等生育结局的风险（比值比[OR]和 95%置信区间[CI]）。
与早期人工流产（<12 孕周）相比，晚期人工流产（≥12 孕周）的妇女发生极早产（OR 2.28；95%CI 1.53-3.39）和极低出生体重（OR 1.62；95%CI 1.22-2.16）的风险更高；调整妇女背景特征、流产方法和妊娠间隔后仍如此。当分析仅限于单次流产时，极早产的风险增加（OR 1.71；95%CI 1.02-2.81）。与两次或更多早期人工流产相比，两次或更多晚期人工流产的妇女发生极早产（OR 4.09；95%CI 2.05-8.18）和极低出生体重（OR 2.65；95%CI 1.61-4.35）的风险更高。与早期人工流产相比，晚期人工流产后不良生育结局的风险更高。
如果有的话，随后发生不良生育结局的风险非常小，但人工流产时的孕龄越大，风险越高。我们的研究支持减少非意愿妊娠，并提供无延迟和尽早的堕胎服务。
