Einum Anders, Nilsen Roy Miodini, Harmon Quaker E, Sørbye Linn Marie, Morken Nils-Halvdan
Department of Clinical Science, University of Bergen, Bergen, Norway.
Department of Obstetrics and Gynecology, Haukeland University Hospital, Bergen, Norway.
Acta Obstet Gynecol Scand. 2025 Aug;104(8):1443-1451. doi: 10.1111/aogs.15147. Epub 2025 Jun 2.
Randomized trials have shown that progesterone treatment in mothers with a short cervix may reduce the risk of preterm birth, but the optimal time window for treatment remains unknown. We aimed to investigate progesterone treatment for the prevention of preterm birth by gestational age at diagnosis and initiation of treatment.
This was a population-based historical cohort study of 1162 mothers with singleton pregnancies diagnosed with a cervix <20 mm from 16 to 31 gestational weeks receiving progesterone treatment (n = 390) or no preventive treatment (n = 772). Data were collected from the Medical Birth Registry of Norway from 2014 to 2020 and linked to national health registries providing demographic, diagnostic, and prescription information. Risks of preterm birth <28, <34, and <37 gestational weeks were compared between mothers with and without progesterone treatment in the full study sample and in three periods of gestational age at diagnosis (16-21, 22-27, and 28-31 weeks) using log-binomial regression analyses.
The absolute risk of preterm birth <28 gestational weeks was 0.8% in mothers treated with progesterone and 3.4% in mothers who did not receive treatment (adjusted relative risk (aRR) 0.25, 95% confidence interval (CI) 0.08-0.81). The strongest protective association was observed in mothers diagnosed from 16 to 21 weeks (aRR 0.13, 95% CI 0.02-0.98). Preterm birth <34 weeks occurred in 8.7% of mothers in the progesterone group and 11.1% in the untreated group (aRR 0.80, 95% CI 0.54-1.17), and the relative risk reduction associated with treatment diminished with increasing gestational age at diagnosis: aRR 0.27 (95% CI 0.08-0.96) from 16 to 21 weeks; aRR 0.68 (95% CI 0.38-1.23) from 22 to 27 weeks; and aRR 1.30 (95% CI 0.71-2.39) from 28 to 31 weeks. There was no difference in the risk of birth <37 weeks in mothers treated with progesterone (23.1%) and untreated mothers (22.3%), and the risk estimates were similar in the three periods of gestational age at diagnosis.
Compared to no treatment, progesterone treatment is associated with a reduced risk of preterm birth <28 gestational weeks in pregnancies with a short cervix. The preventive effect of treatment may extend to 34 weeks if treatment is initiated early in the second trimester.
随机试验表明，对宫颈短的母亲进行孕激素治疗可能会降低早产风险，但最佳治疗时间窗仍不清楚。我们旨在研究根据诊断时的孕周和开始治疗的时间进行孕激素治疗以预防早产的情况。
这是一项基于人群的历史性队列研究，研究对象为1162名单胎妊娠母亲，她们在妊娠16至31周时被诊断为宫颈长度<20mm，其中390名接受了孕激素治疗，772名未接受预防性治疗。数据收集自2014年至2020年挪威医疗出生登记处，并与提供人口统计学、诊断和处方信息的国家健康登记处相链接。使用对数二项回归分析比较了整个研究样本中以及诊断时孕周的三个时间段（16 - 21周、22 - 27周和28 - 31周）接受和未接受孕激素治疗的母亲发生<28周、<34周和<37周早产的风险。
接受孕激素治疗的母亲发生<28周早产的绝对风险为0.8%，未接受治疗的母亲为3.4%（调整后相对风险（aRR）为0.25，95%置信区间（CI）为0.08 - 0.81）。在妊娠16至21周被诊断的母亲中观察到最强的保护关联（aRR为0.13，95%CI为0.02 - 0.98）。孕激素组8.7%的母亲发生<34周早产，未治疗组为11.1%（aRR为0.80，95%CI为0.54 - 1.17），且随着诊断时孕周增加，治疗相关的相对风险降低幅度减小：16至21周时aRR为0.27（95%CI为0.08 - 0.96）；22至27周时aRR为0.68（95%CI为0.38 - 1.23）；28至31周时aRR为1.30（95%CI为0.71 - 2.39）。接受孕激素治疗母亲（23.1%）和未治疗母亲（22.3%）发生<37周分娩的风险没有差异，且在诊断时孕周的三个时间段风险估计相似。
与不治疗相比，孕激素治疗可降低宫颈短的妊娠中<28周早产的风险。如果在孕中期早期开始治疗，则治疗预防效果可能会延长至34周。
