# Impact of maternal body mass index and gestational comorbidities on the birth prevalence of orofacial clefts in the Japan Environment and Children’s Study

## TL;DR

This study finds that high maternal BMI and gestational conditions like hypertension increase the risk of orofacial clefts in newborns.

## Contribution

The study identifies the combined impact of high BMI and gestational comorbidities on orofacial cleft birth prevalence.

## Key findings

- Mothers with high BMI had a 1.58 times higher odds of having a child with CL/P.
- Gestational hypertension combined with high BMI increased CL/P odds by 2.91 times.
- Gestational diabetes combined with high BMI increased CL/P odds by 2.12 times.

## Abstract

An increased prevalence of cleft lip and/or palate (CL/P), a major congenital anomaly, has been observed in the offspring of women with elevated body mass index (BMI) before pregnancy. Likewise, gestational comorbidities, such as hypertension and diabetes mellitus, also increase the risk of CL/P; however, the risk linked to the coexistence of these conditions in women with higher BMI on birth prevalence of CL/P remains unclear. This study focused on the combined effects of a high BMI before pregnancy and gestational comorbidities on the birth prevalence of CL/P.

Among 98,373 live births from the Japan Environment and Children’s Study (JECS), a nationwide birth cohort, 255 mothers of infants with CL/P (74, 112, and 69 infants born with cleft lip, cleft lip and palate, and isolated cleft palate, respectively) were included in the analyses. The association of CL/P birth prevalence with pre-pregnancy BMI and gestational comorbidities (hypertension and diabetes) was examined using multivariate logistic regression analyses after multiple imputations, with adjustments for several maternal (age at delivery, smoking habits, and alcohol intake) and child-related (sex and prevalence of other congenital diseases) variables, obtained through medical record transcriptions and self-reports on JECS transcription forms.

Higher prevalence rates of overweight, gestational hypertension, and gestational diabetes mellitus were found in mothers of infants with CL/P (16.1%, 6.3%, and 4.7%, respectively) than in the control group (10.4%, 3.1%, and 3.1%, respectively). The odds ratio [95% confidence interval] for childbirth with CL/P was increased in mothers with high BMI before pregnancy (1.58 [1.11–2.24]). Furthermore, gestational hypertension and diabetes coexisting with high BMI additionally increased the odds ratios for childbirth with CL/P (2.91 [1.28–6.61] and 2.12 [0.87–5.19], respectively).

High maternal BMI, particularly when accompanied by gestational hypertension, was significantly associated with an increased prevalence of childbirth with CL/P.

The online version contains supplementary material available at https://doi.org/10.1265/ehpm.25-00205.