Maternal excessive weight gain as a potential risk factor for prolonged labor in Japanese pregnant women: The Japan Environment and Children's Study

Satoshi Shinohara; Sayaka Horiuchi; Reiji Kojima; Ryoji Shinohara; Sanae Otawa; Megumi Kushima; Kunio Miyake; Hideki Yui; Tadao Ooka; Yuka Akiyama; Hiroshi Yokomichi; Zentaro Yamagata; Japan Environment and Children’s Study Group

doi:10.1371/journal.pone.0306247

Maternal excessive weight gain as a potential risk factor for prolonged labor in Japanese pregnant women: The Japan Environment and Children's Study

PLoS One. 2024 Jul 3;19(7):e0306247. doi: 10.1371/journal.pone.0306247. eCollection 2024.

Affiliations

¹ Department of Obstetrics and Gynecology, Yamanashi Prefectural Central Hospital, Kofu, Yamanashi, Japan.
² Center for Birth Cohort Studies, University of Yamanashi, Chuo, Yamanashi, Japan.
³ Department of Health Sciences, School of Medicine, University of Yamanashi, Chuo, Yamanashi, Japan.

Abstract

Aim: This study aimed to determine whether excessive maternal weight gain during pregnancy was associated with a higher risk of prolonged labor.

Methods: We analyzed the data regarding maternal weight gain during pregnancy for the participants of Japan Environment and Children's Study (JECS), which is an ongoing nationwide prospective birth cohort study in Japan. After excluding participants with multiple pregnancies, with deliveries before 37 or beyond 42 weeks of gestation, or who had undergone cesarean section, 71,154 (nulliparous, n = 28,442) Japanese women were included. Prolonged labor was defined by a cutoff ranking at the 95th percentile and consequently defined as labor duration exceeding 12.7 h in multiparous women and exceeding 23.2 h in nulliparous women. These classifications were made according to labor curves established by the Japanese Society of Obstetrics and Gynecology Perinatal Committee developed in June 2021. Considering that no studies have conducted an investigation based on this new guideline, we analyzed the association between excessive maternal weight gain during pregnancy and prolonged labor by parity.

Results: The overall incidence of prolonged labor was 10.2% (2,907/28,442) in nulliparous women and 6.1% (2,597/42,712) in multiparous women. Multivariable analysis indicated that excessive maternal weight gain was significantly associated with prolonged labor in nulliparous (adjusted odds ratio, 1.21; 95% confidence interval, 1.10-1.32) and multiparous women (adjusted odds ratio, 1.15; 95% confidence interval, 1.05-1.27). Kaplan-Meier survival analysis showed that as labor progressed, the percentage of women who had not yet delivered was higher among those with excessive maternal weight gain than among those with normal maternal weight gain in both the nulliparous (median labor duration 12.9 h vs 12.2 h, p<0.001) and multiparous (median labor duration 6.2 h vs 5.8 h, p<0.001) groups.

Conclusion: Excessive maternal weight gain was significantly associated with prolonged labor in Japanese women.

Copyright: © 2024 Shinohara et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

MeSH terms

Adult
East Asian People
Female
Gestational Weight Gain
Humans
Japan / epidemiology
Labor, Obstetric / physiology
Obstetric Labor Complications / epidemiology
Parity*
Pregnancy
Prospective Studies
Risk Factors
Weight Gain

Grants and funding

This research was supported by the Ministry of Environment, Japan, in the form of a grant to the Japan Environment and Children’s Study” as Funding Information. However, no grant number has been received. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.