Vaajala Matias, Liukkonen Rasmus, Mattila Ville M, Kekki Maiju, Kuitunen Ilari
Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland.
Department of Orthopaedics and Traumatology, Tampere University Hospital Tampere, Tampere, Finland.
Int J Gynaecol Obstet. 2025 Mar;168(3):1161-1170. doi: 10.1002/ijgo.15982. Epub 2024 Oct 27.
The study aimed to calculate the subsequent birth rate for different delivery modes, comparing them with spontaneous vaginal deliveries, using a comprehensive nationwide high-quality registry.
Data from the National Medical Birth Register (MBR) were used to evaluate the birth rate after different delivery modes. All first deliveries for a mother during the years 2004 to 2016 were included. For these women, all second pregnancies from the MBR during the years 2004 to 2018 were retrieved and combined with the data of the first deliveries. A Cox regression model was used to evaluate the risk for the second pregnancy after giving birth the first time. The results were interpreted with adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs).
A total of 375 619 women with a first and second pregnancy leading to birth were included in this study. Of these, a total of 50 579 women underwent assisted vaginal delivery, 50 429 had an unplanned cesarean section (CS), 22 021 had elective CS, and 252 593 had spontaneous vaginal delivery as a mode of delivery in their first pregnancy. Women with assisted vaginal delivery (aHR, 1.23 [CI, 1.21-1.24]) and unplanned CS (aHR, 1.03 [CI, 1.02-1.05]) had higher birth rates after the first birth, and women with elective CS as a mode of delivery had lower birth rates (aHR, 0.86 [CI, 0.84-0.88]) when compared with women who had spontaneous vaginal delivery.
The findings of this study indicate that the CS operation itself is not the only cause of the observed lower birth rate; rather, there are underlying factors that have a greater impact on birth rates.
本研究旨在利用全国范围的高质量综合登记系统，计算不同分娩方式的后续出生率，并与自然阴道分娩进行比较。
利用国家医疗出生登记处（MBR）的数据评估不同分娩方式后的出生率。纳入2004年至2016年期间母亲的所有首次分娩。对于这些女性，检索了2004年至2018年期间MBR中的所有第二次妊娠情况，并与首次分娩数据相结合。采用Cox回归模型评估首次分娩后第二次妊娠的风险。结果用调整后的风险比（aHRs）和95%置信区间（CIs）进行解释。
本研究共纳入375619名有首次和第二次妊娠并分娩的女性。其中，共有50579名女性接受了阴道助产，50429名进行了非计划剖宫产（CS），22021名进行了择期剖宫产，252593名在首次妊娠时以自然阴道分娩作为分娩方式。与自然阴道分娩的女性相比，阴道助产的女性（aHR，1.23[CI，1.21 - 1.24]）和非计划剖宫产的女性（aHR，1.03[CI，1.02 - 1.05]）首次分娩后的出生率较高，而择期剖宫产作为分娩方式的女性出生率较低（aHR，0.86[CI，0.84 - 0.88]）。
本研究结果表明，剖宫产手术本身并非观察到的较低出生率的唯一原因；相反，存在对出生率有更大影响的潜在因素。
