School of Primary Care, Population Sciences and Medical Education, Faculty of Medicine, University of Southampton, Southampton, United Kingdom.
NIHR Southampton Biomedical Research Centre, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom.
PLoS One. 2019 Nov 21;14(11):e0225400. doi: 10.1371/journal.pone.0225400. eCollection 2019.
The relationship between maternal weight change between pregnancies and premature birth is unclear. This study aimed to investigate whether interpregnancy weight change between first and second, or second and third pregnancy is associated with premature birth.
Routinely collected data from 2003 to 2018 from one English maternity centre was used to produce two cohorts. The primary cohort (n = 14,961 women) consisted of first and second live-birth pregnancies. The secondary cohort (n = 5,108 women) consisted of second and third live-birth pregnancies. Logistic regression models were used to examine associations between interpregnancy BMI change and premature births adjusted for confounders. Subgroup analyses were carried out, stratifying by initial pregnancy BMI groups and analysing spontaneous and indicated premature births separately.
In the primary cohort, 3.4% (n = 514) of births were premature compared to 4.2% (n = 212) in the secondary cohort, with fewer indicated than spontaneous premature births in both cohorts.
Weight loss (>3kg/m2) was associated with increased odds of premature birth (adjusted odds ratio (aOR):3.50, 95% CI: 1.78-6.88), and spontaneous premature birth (aOR: 3.34, 95%CI: 1.60-6.98), in women who were normal weight (BMI 18.5-25kg/m2) at first pregnancy. Weight gain >1kg/m2 was not associated with premature birth regardless of starting BMI.
Losing >3kg/m2 was associated with increased odds of premature birth (aOR: 2.01, 95%CI: 1.05-3.87), when analysing the whole sample, but not when restricting the analysis to women who were overweight or obese at second pregnancy.
Normal-weight women who lose significant weight (>3kg/m2) between their first and second live pregnancies have greater odds of premature birth compared to normal-weight women who remain weight stable in the interpregnancy period. There was no evidence of association between weight change in women who were overweight or obese at the start of their first pregnancy and premature birth.
妊娠间体重变化与早产之间的关系尚不清楚。本研究旨在探讨首次妊娠和第二次妊娠或第二次妊娠和第三次妊娠间体重变化与早产的关系。
使用 2003 年至 2018 年一家英国产科中心的常规收集数据产生了两个队列。主要队列（n=14961 名妇女）包括首次和第二次活产妊娠。次要队列（n=5108 名妇女）包括第二次和第三次活产妊娠。使用逻辑回归模型调整混杂因素后，检查妊娠间 BMI 变化与早产之间的关联。进行了亚组分析，按初始妊娠 BMI 组分层，并分别分析自发性和指征性早产。
在主要队列中，3.4%（n=514）的分娩为早产，而在次要队列中，4.2%（n=212）的分娩为早产，两个队列中的指征性早产均少于自发性早产。
体重减轻（>3kg/m2）与早产（调整后的优势比（aOR）：3.50，95%置信区间（CI）：1.78-6.88）和自发性早产（aOR：3.34，95%CI：1.60-6.98）的风险增加相关，在首次妊娠时体重正常（BMI 18.5-25kg/m2）的妇女中。无论起始 BMI 如何，体重增加>1kg/m2与早产无关。
在整个样本中，体重减轻>3kg/m2与早产的风险增加相关（aOR：2.01，95%CI：1.05-3.87），但在将分析仅限于第二次妊娠时超重或肥胖的妇女时则不然。
与在妊娠间保持体重稳定的体重正常的妇女相比，首次和第二次活产妊娠间体重显著减轻（>3kg/m2）的正常体重妇女早产的风险更高。在首次妊娠时超重或肥胖的妇女中，体重变化与早产之间没有关联的证据。
