Zeitlin Jennifer, Blondel Béatrice, Ananth Cande V
Obstetrical, Perinatal and Pediatric Epidemiology Research Team (Epopé), INSERM, Center for Epidemiology and Statistics Sorbonne Paris, Paris Descartes University, 53 Avenue de L'Observatoire, 75014, Paris, France.
Matern Child Health J. 2015 May;19(5):1107-14. doi: 10.1007/s10995-014-1602-0.
Preterm delivery rates have remained consistently higher in the US than France, but the reasons for this excess remain poorly understood. We examined if differences in socio-demographic risk factors or more liberal use of obstetrical interventions contributed to higher rates in the US. Data on singleton live births in 1995, 1998 and 2003 from US birth certificates and the French National Perinatal Survey were used to analyze preterm delivery rate by maternal characteristics (age, parity, marital status, education, race (US)/nationality (France), prenatal care and smoking). We distinguished between preterm deliveries with a cesarean or a labor induction and those without these interventions. Unadjusted and adjusted risk ratios (RR) for the US compared to France were estimated using log-binomial regression. Preterm delivery rates were 7.9 % in the US and 4.7 % in France (risk ratio [RR] = 1.7, 95 % confidence interval [CI] 1.6-1.8). The US had more teen mothers and late entry to prenatal care, but fewer women smoked, although adjustment for these and other confounders did not reduce RR (1.8, 95 % CI 1.7-1.9). Preterm delivery rates associated with labor induction or cesarean were 3.3 % in the US and 2.1 % in France (RR 1.6, 95 % CI 1.5-1.7); the corresponding rates for preterm delivery without these interventions were 4.5 and 2.5 % (RR 1.8, 95 % CI 1.7-1.9), respectively. Key socio-demographic risk factors and more obstetric intervention do not explain higher US preterm delivery rates. Avenues for future research include the impact of universal access to health services (universal health insurance?) on health care quality and the association between more generous social policies, stress and the risks of preterm delivery.
美国的早产率一直高于法国，但造成这种差异的原因仍知之甚少。我们研究了社会人口风险因素的差异或产科干预措施的更广泛使用是否导致了美国较高的早产率。利用1995年、1998年和2003年美国出生证明和法国国家围产期调查中关于单胎活产的数据，按产妇特征（年龄、产次、婚姻状况、教育程度、种族（美国）/国籍（法国）、产前护理和吸烟情况）分析早产率。我们区分了剖宫产或引产导致的早产与未进行这些干预措施的早产情况。采用对数二项回归法估计美国与法国相比的未调整和调整风险比（RR）。美国的早产率为7.9%，法国为4.7%（风险比[RR]=1.7，95%置信区间[CI]1.6 - 1.8）。美国青少年母亲更多，产前护理开始时间晚，但吸烟的女性较少，不过对这些因素及其他混杂因素进行调整后并未降低RR（1.8，95% CI 1.7 - 1.9）。与引产或剖宫产相关的早产率在美国为3.3%，在法国为2.1%（RR 1.6，95% CI 1.5 - 1.7）；未进行这些干预措施的早产率分别为4.5%和2.5%（RR 1.8，95% CI 1.7 - 1.9）。关键的社会人口风险因素和更多的产科干预并不能解释美国较高的早产率。未来研究的方向包括普遍获得医疗服务（全民健康保险？）对医疗质量的影响以及更慷慨的社会政策、压力与早产风险之间的关联。
