O'Neill Sinéad M, Khashan Ali S, Henriksen Tine B, Kenny Louise C, Kearney Patricia M, Mortensen Preben B, Greene Richard A, Agerbo Esben
National Perinatal Epidemiology Centre, Department of Obstetrics and Gynaecology, Cork University Maternity Hospital, 5th Floor, Wilton, Cork, Ireland
The Irish Centre for Fetal and Neonatal Translational Research (INFANT), University College Cork, Cork, Ireland Department of Obstetrics and Gynaecology, University College Cork, Cork, Ireland.
Hum Reprod. 2014 Nov;29(11):2560-8. doi: 10.1093/humrep/deu217. Epub 2014 Sep 12.
Does a primary Caesarean section influence the rate of, and time to, subsequent live birth compared with vaginal delivery?
Caesarean section was associated with a reduction in the rate of subsequent live birth, particularly among elective and maternal-requested Caesareans indicating maternal choice plays a role.
Several studies have examined the relationship between Caesarean section and subsequent birth rate with conflicting results primarily due to poor epidemiological methods.
STUDY DESIGN, SIZE, DURATION: This Danish population register-based cohort study covered the period from 1982 to 2010 (N = 832 996).
PARTICIPANTS/MATERIALS, SETTING, METHODS: All women with index live births were followed until their subsequent live birth or censored (maternal death, emigration or study end) using Cox regression models.
In all 577 830 (69%) women had a subsequent live birth. Women with any type of Caesarean had a reduced rate of subsequent live birth (hazard ratio [HR] 0.86, 95% confidence intervals [CI] 0.85, 0.87) compared with spontaneous vaginal delivery. This effect was consistent when analyses were stratified by type of Caesarean: emergency (HR 0.87, 95% CI 0.86, 0.88), elective (HR 0.83, 95% CI 0.82, 0.84) and maternal-requested (HR 0.61, 95% CI 0.57, 0.66) and in the extensive sub-analyses performed.
LIMITATIONS, REASONS FOR CAUTION: Lack of biological data to measure a woman's fertility is a major limitation of the current study. Unmeasured confounding and limited availability of data (maternal BMI, smoking, access to fertility services and maternal-requested Caesarean section) as well as changes in maternity care over time may also influence the findings.
This is the largest study to date and shows that Caesarean section is most likely not causally related to a reduction in fertility. Maternal choice to delay or avoid childbirth is the most plausible explanation. Our findings are generalizable to other middle- to high-income countries; however, cross country variations in Caesarean section rates and social or cultural differences are acknowledged.
STUDY FUNDING/COMPETING INTERESTS: Funding was provided by the National Perinatal Epidemiology Centre, Cork, Ireland and conducted as part of the Health Research Board PhD Scholars programme in Health Services Research (Grant No. PHD/2007/16). L.C.K. is a Science Foundation Ireland Principal Investigator (08/IN.1/B2083) and the Director of the SFI funded Centre, INFANT (12/RC/2272). The authors have no competing interests to declare.
与阴道分娩相比，初次剖宫产是否会影响后续活产率及活产时间？
剖宫产与后续活产率降低有关，尤其是在选择性剖宫产和产妇要求的剖宫产中，这表明产妇选择起到了一定作用。
多项研究探讨了剖宫产与后续出生率之间的关系，但结果相互矛盾，主要原因是流行病学方法欠佳。
研究设计、规模、持续时间：这项基于丹麦人口登记的队列研究涵盖了1982年至2010年期间（N = 832996）。
研究对象/材料、研究环境、方法：所有有首次活产的女性均被随访至其后续活产或被截尾（产妇死亡、移民或研究结束），采用Cox回归模型。
在所有研究对象中，577830名（69%）女性有后续活产。与自然阴道分娩相比，任何类型剖宫产的女性后续活产率均降低（风险比[HR] 0.86，95%置信区间[CI] 0.85，0.87）。当按剖宫产类型分层分析时，这种效应是一致的：急诊剖宫产（HR 0.87，95% CI 0.86，0.88）、选择性剖宫产（HR 0.83，95% CI 0.82，0.84）和产妇要求的剖宫产（HR 0.61，95% CI 0.57，0.66），在进行的广泛亚组分析中也是如此。
局限性、需谨慎的原因：缺乏测量女性生育能力的生物学数据是本研究的主要局限性。未测量的混杂因素、数据可用性有限（产妇BMI、吸烟、获得生育服务情况和产妇要求的剖宫产）以及随着时间推移产科护理的变化也可能影响研究结果。
这是迄今为止规模最大的研究，表明剖宫产很可能与生育能力降低没有因果关系。产妇选择推迟或避免生育是最合理的解释。我们的研究结果可推广到其他中高收入国家；然而，承认剖宫产率在不同国家存在差异以及社会或文化差异。
研究资金/利益冲突：资金由爱尔兰科克国家围产期流行病学中心提供，作为健康研究委员会健康服务研究博士学者项目的一部分进行（资助编号PHD/2007/16）。L.C.K.是爱尔兰科学基金会首席研究员（08/IN.1/B2083）以及由科学基金会资助的INFANT中心主任（12/RC/2272）。作者声明无利益冲突。
