Voigt M, Briese V, Carstensen M, Wolterdorf F, Hallier E, Straube S
Institute for Perinatal Auxology, Klinikum Südstadt, Rostock, Germany.
Z Geburtshilfe Neonatol. 2010 Aug;214(4):161-6. doi: 10.1055/s-0030-1254140. Epub 2010 Aug 30.
A description of preterm birth rates - specified according to maternal age - after the exclusion of anamnestic risk factors.
Data for this study were taken from the German Perinatal Survey of 1998-2000. We analysed data from 492,576 singleton pregnancies and determined preterm birth rates according to maternal age after a stepwise exclusion of anamnestic risk factors.
There was a U-shaped dependence of preterm birth rates on maternal age. The lowest preterm birth rate (without excluding women with anamnestic risk factors) was 5.6% at a maternal age of 29 years. The prevalence of some anamnestic risk factors for preterm birth, such as previous stillbirths, spontaneous and induced abortions, and ectopic pregnancies, increased with maternal age. Excluding women with anamnestic risk factors lowered the preterm birth rates substantially. The lowest preterm birth rates were found in women with one previous live birth, without any anamnestic risk factors, and with a body mass index (BMI) of 25.00-29.99. With these restrictions, we found preterm birth rates of under 2% for women aged 24-31 years.
The magnitude and age-dependence of the preterm birth rate can to some extent be explained with the age-dependent prevalence of anamnestic risk factors for preterm birth. Excluding women with anamnestic risk factors from our study population lowered the preterm birth rates substantially.
描述排除既往风险因素后，按母亲年龄划分的早产率。
本研究数据取自1998 - 2000年德国围产期调查。我们分析了492,576例单胎妊娠的数据，并在逐步排除既往风险因素后，根据母亲年龄确定早产率。
早产率与母亲年龄呈U形关系。（未排除有既往风险因素的女性时）母亲年龄为29岁时早产率最低，为5.6%。一些早产的既往风险因素，如既往死产、自然流产和人工流产以及异位妊娠的发生率随母亲年龄增加而上升。排除有既往风险因素的女性后，早产率大幅降低。早产率最低的是既往有一次活产、无任何既往风险因素且体重指数（BMI）为25.00 - 29.99的女性。在这些限制条件下，我们发现24 - 31岁女性的早产率低于2%。
早产率的大小和年龄依赖性在一定程度上可以用早产既往风险因素的年龄依赖性发生率来解释。从我们的研究人群中排除有既往风险因素的女性后，早产率大幅降低。
