Interpregnancy weight change as a potential risk factor for large-for-gestational-age infants: the Japan Environment and Children’s Study

Abstract

Objective

This study aimed to estimate the impact of interpregnancy weight change from the first to the second pregnancy on the risk of infants being large for gestational age (LGA).

Methods

This nationwide prospective birth cohort analysis included 3245 women who delivered their first two live singletons between 2011 and 2014. Interpregnancy weight change was calculated as the difference between the prepregnancy body mass index (BMI) of the first and second pregnancies. LGA infants were compared among three interpregnancy weight change groups: weight loss (a BMI loss >1 unit), weight gain (a BMI gain >1 unit), and stable weight (BMI maintained within − 1 to <1 unit). Interpregnancy weight change was assessed in mothers with a BMI <25 and ≥25 kg/m², and adjusted odds ratios (ORs) were calculated for LGA infants by multiple logistic regression.

Results

The incidence of LGA infants was 8.6% (279 out of 3245). Compared with the stable weight group, interpregnancy weight gain was associated with an increased risk of infants being LGA (adjusted OR: 1.69, 95% confidence interval: 1.21–2.36) in the normal BMI (<25 kg/m²) group. In contrast, in the overweight/obese BMI (≥25 kg/m²) group, interpregnancy BMI was not a significant risk factor for LGA infants.

Conclusions

Accurate risk stratification using interpregnancy BMI could assist the clinical management of women with a normal BMI who are at risk of delivering LGA infants.

Keywords:

• LGA
• interpregnancy BMI
• overweight
• obese
• infant

Acknowledgements

The authors are grateful to the participants of the JECS. Members of the JECS Group as of 2022: Michihiro Kamijima (principal investigator, Nagoya City University, Nagoya, Japan), Shin Yamazaki (National Institute for Environmental Studies, Tsukuba, Japan), Yukihiro Ohya (National Center for Child Health and Development, Tokyo, Japan), Reiko Kishi (Hokkaido University, Sapporo, Japan), Nobuo Yaegashi (Tohoku University, Sendai, Japan), Koichi Hashimoto (Fukushima Medical University, Fukushima, Japan), Chisato Mori (Chiba University, Chiba, Japan), Shuichi Ito (Yokohama City University, Yokohama, Japan), Zentaro Yamagata (University of Yamanashi, Chuo, Japan), Hidekuni Inadera (University of Toyama, Toyama, Japan), Takeo Nakayama (Kyoto University, Kyoto, Japan), Tomotaka Sobue (Osaka University, Suita, Japan), Masayuki Shima (Hyogo Medical University, Nishinomiya, Japan), Hiroshige Nakamura (Tottori University, Yonago, Japan), Narufumi Suganuma (Kochi University, Nankoku, Japan), Koichi Kusuhara (University of Occupational and Environmental Health, Kitakyushu, Japan), and Takahiko Katoh (Kumamoto University, Kumamoto, Japan).

Author contributions

S Shinohara had full access to all data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Concept and design: S Shinohara. Acquisition, analysis, or interpretation of data: All authors. Drafting of the manuscript: All authors. Critical revision of the manuscript for important intellectual content: All authors. Statistical analysis: S Shinohara. Administrative, technical, or material support: R Shinohara. Supervision: S Shinohara, Z Yamagata.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Data are unsuitable for public deposition due to ethical restrictions and the legal framework of Japan. It is prohibited by the Act on the Protection of Personal Information (Act No. 57 of 30 May 2003, amended on 9 September 2015) to publicly deposit data containing personal information. Ethical Guidelines for Medical and Health Research Involving Human Subjects enforced by the Japan Ministry of Education, Culture, Sports, Science and Technology and the Ministry of Health, Labor and Welfare also restrict the open sharing of epidemiological data. All inquiries about access to data should be sent to [email protected]. The person responsible for handling inquiries sent to this e-mail address is Dr Shoji F. Nakayama, JECS Program Office, National Institute for Environmental Studies.

Additional information

Funding

The JECS was funded by the Ministry of the Environment, Japan. The findings and conclusions of this study are solely the responsibility of the authors and do not represent the official views of the aforementioned Japanese government agencies.