Investigation of appropriate weight gain for twin pregnancies using the Japan Society of Obstetrics and Gynecology Successive Pregnancy Birth Registry System

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K18700
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 56040:Obstetrics and gynecology-related
• Research Institution: Yokohama City University
• Principal Investigator: OBATA SOICHIRO 横浜市立大学, 附属市民総合医療センター, 助教 (40769345)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 双胎妊娠 / 体重 / 妊娠分娩転帰

Outline of Final Research Achievements

The study included cases of dichorionic diamniotic twin pregnancy registered in the Japan Society of Obstetrics and Gynecology Successive Pregnancy Birth Registry System between 2013 and 2017. We analyzed data for cases wherein both babies were appropriate for gestational age and delivered at term. Cases were classified into four groups based on the pre-pregnancy BMI: underweight (BMI <18.5 kg/m2), normal weight (18.5-< 25.0 kg/m2), overweight (25.0-30.0 kg/m2), and obese (BMI>30.0 kg/m2) and we calculated the 25th-75th percentile range for GWG for the cases. The GWG ranges were 11.5-16.5 kg, 10.3-16.0 kg, 6.9-14.7 kg, and 2.2-11.7 kg in the underweight, normal weight, overweight, and obese groups, respectively. Thus, in the current study, the optimal GWG during twin pregnancy was lower than that specified by the IOM criteria. Factoring this in maternal management may improve the outcomes of twin pregnancies in Japan.

Free Research Field

周産期医学

Academic Significance and Societal Importance of the Research Achievements

本邦における双胎妊娠例の適正体重増加量に関するエビデンスはこれまでなかったが、今回の研究報告により、その値は本邦の単胎妊娠の適正体重増加量よりも多いことが示された。また、その適正体重増加量は米国の基準は大きく下回ることが明らかになり、人種差をより考慮することの重要性が示された。これまでは妊婦健診等の指導において用いることのできるエビデンスは乏しかったが、本邦の研究成果により、妊産婦に対して正確でありかつ具体的な指導を行うために有用なエビデンスを構築することができた。