Department of Clinical Sciences and Community Health, University of Milan, 20122, Milan, Italy.
Department of Woman, Newborn and Child, University of Milan, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122, Milan, Italy.
BMC Pregnancy Childbirth. 2022 Mar 22;22(1):234. doi: 10.1186/s12884-022-04552-y.
All over the world, especially in the developed countries, maternal age at birth is rising. This study aimed to assess the role of maternal age on the occurrence of preterm birth (PTB) in a large birth cohort of Lombardy Region, Northern Italy.
This population-based study used data from regional healthcare utilization databases of Lombardy to identify women who delivered between 2007 and 2017. PTBs were defined as births before 37 completed weeks of gestation and considered according to the gestational age (two categories: < 32 weeks and 32 to 36 weeks). Six maternal age groups were defined (< 20, 20-24, 25-29, 30-34, 35-39, ≥40 years). Logistic regression models were fitted to estimate the crude and adjusted odds ratio (aOR) and the corresponding 95% confidence interval (CI) for PTB among different maternal age groups. Analyses were separately performed according to type of pregnancy (singletons and multiples). Reference group was the age group with the lowest frequency of PTB.
Overall, 49,759 (6.6%) PTBs were observed, of which 41,807 were singletons and 7952 were multiples. Rates of PTB were lowest in the women aged 25-29 years among singletons and in the 30-34 years old group among multiples. Our results described a U-shaped association between maternal age and risk of PTB. In particular, the risk of a singleton PTB between 32 and 36 weeks was significantly higher for women aged less than 20 years (aOR = 1.16, CI 95%: 1.04-1.30) and more than 40 years (aOR = 1.62 CI 95%: 1.54-1.70). The highest risk of a multiple delivery between 32 and 36 weeks was observed among women aged less than 25 years and more than 40 years (aOR = 1.79, CI 95%: 1.01-3.17, aOR = 1.47, CI 95%: 1.16-1.85 and aOR = 1.36, CI 95%: 1.19-1.55 respectively for < 20, 20-24 and > 40 age categories). PTB before 32 completed weeks occurred more frequently in the same age categories, except that among multiples no association with advanced maternal age emerged.
Our study suggested that, after adjustment for potential confounders, both advance and young maternal age were associated with an increased risk of PTB.
在世界范围内，尤其是在发达国家，产妇的生育年龄正在上升。本研究旨在评估在意大利北部伦巴第大区的一个大型出生队列中，产妇年龄对早产（PTB）发生的作用。
本基于人群的研究使用了伦巴第地区医疗保健利用数据库中的数据，以确定 2007 年至 2017 年间分娩的女性。早产被定义为在妊娠 37 周前分娩，并根据胎龄（两个类别：<32 周和 32-36 周）进行考虑。定义了六个产妇年龄组（<20 岁、20-24 岁、25-29 岁、30-34 岁、35-39 岁、≥40 岁）。使用逻辑回归模型来估计不同产妇年龄组中 PTB 的粗比值比（OR）和调整后的比值比（aOR）以及相应的 95%置信区间（CI）。根据妊娠类型（单胎和多胎）分别进行分析。参考组是 PTB 发生率最低的年龄组。
总体而言，观察到 49759 例（6.6%）PTB，其中 41807 例为单胎，7952 例为多胎。在单胎中，25-29 岁的女性和多胎中 30-34 岁的女性 PTB 发生率最低。我们的结果描述了产妇年龄与 PTB 风险之间的 U 形关联。特别是，20 岁以下和 40 岁以上的女性，其单胎妊娠 32-36 周的 PTB 风险显著增加（aOR=1.16，95%CI：1.04-1.30 和 aOR=1.62，95%CI：1.54-1.70）。25 岁以下和 40 岁以上的女性多胎妊娠 32-36 周的分娩风险最高（aOR=1.79，95%CI：1.01-3.17，aOR=1.47，95%CI：1.16-1.85 和 aOR=1.36，95%CI：1.19-1.55 分别用于<20、20-24 和>40 年龄组）。32 周前的早产更常发生在相同的年龄组中，但在多胎妊娠中，与高龄产妇没有关联。
我们的研究表明，在校正潜在混杂因素后，产妇年龄提前和年轻都与 PTB 风险增加有关。
