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

Figures & data

Table 1. Comparison of SGA and LGA according to interpregnancy BMI.

	BMI loss (< −1 unit)	Stable BMI (−1 to <1 unit)	BMI gain (≥1 unit)	p Value
Prepregnancy BMI <25 kg/m^2	n = 321	n = 1916	n = 622
SGA infants	24 (7.5)	150 (7.8)	44 (7.1)	.82
LGA infants	22 (6.9)	129 (6.7)	62 (10.0)	.03
Prepregnancy BMI ≥25 kg/m^2	n = 34	n = 112	n = 240
SGA infants	1 (2.9)	3 (2.7)	9 (3.8)	.87
LGA infants	10 (29.4)	18 (16.1)	38 (15.8)	.14

Notes: Data are presented as numbers (%). BMI: body mass index; LGA: large-for-gestational-age; SGA: small-for-gestational-age.

Table 2. Association between interpregnancy BMI and LGA infants.

Prepregnancy BMI <25 kg/m^2
Interpregnancy BMI status	Crude OR (95% CI)	Adjusted OR (95% CI)
BMI loss (< −1 unit)	1.02 (0.64–1.63)	1.03 (0.63–1.67)
Stable BMI (−1 to <1 unit)	Reference	Reference
BMI gain (≥1 unit)	1.53 (1.11–2.11)	1.69 (1.21–2.36)
Prepregnancy BMI ≥25 kg/m^2
Interpregnancy BMI status	Crude OR (95% CI)	Adjusted OR (95% CI)
BMI loss (< −1 unit)	2.17 (0.89–5.32)	1.89 (0.70–5.13)
Stable BMI (−1 to <1 unit)	Reference	Reference
BMI gain (≥1 unit)	0.98 (0.53–1.81)	1.00 (0.51–1.93)

Notes: Multiple logistic regression analysis was performed after adjusting for excessive weight gain, male infant, advanced maternal age, gestational diabetes mellitus or overt diabetes in pregnancy, LGA in the first pregnancy, and interpregnancy BMI. BMI: body mass index; CI: confidence interval; LGA: large-for-gestational-age; OR: odds ratio.

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.