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Published on: June 6, 2020
Body Mass Index and spontaneous miscarriage
Michael J Turner1, Chro Fattah, Norah O'Connor
1UCD Centre for Human Reproduction, Coombe Women and Infants University Hospital, Dublin 8, Ireland. michael.turner@ucd.ie
Summary
Obese women (Body Mass Index >29.9 kg/m(2)) do not have an increased risk of spontaneous miscarriage in early pregnancy. This study found similar low miscarriage rates across different Body Mass Index categories when fetal heart activity was present.
Area of Science:
- Reproductive Medicine
- Maternal-Fetal Medicine
- Obesity Research
Background:
- Obesity is a growing concern in reproductive-aged women.
- The impact of maternal Body Mass Index (BMI) on early pregnancy outcomes, specifically spontaneous miscarriage, requires further clarification.
- Previous studies have yielded conflicting results regarding the association between obesity and miscarriage risk.
Purpose of the Study:
- To compare the incidence of spontaneous miscarriage in obese women (BMI >29.9 kg/m(2)) versus women in other BMI categories.
- To investigate the relationship between maternal body composition and miscarriage risk.
- To determine if maternal obesity affects early pregnancy viability in the presence of confirmed fetal heart activity.
Main Methods:
- Prospective observational study involving 1200 women in the first trimester of pregnancy.
- Maternal height and weight were digitally measured to calculate Body Mass Index (BMI).
- Advanced bioelectrical impedance analysis was used to assess maternal body composition.
Main Results:
- The overall miscarriage rate was 2.8% (33/1200).
- In obese women (BMI >29.9 kg/m(2)), the miscarriage rate was 2.3%, which was not higher than in normal BMI (2.3%) or overweight (3.3%) categories.
- No significant differences in body composition parameters, including fat mass, were found between women who miscarried and those who did not.
Conclusions:
- In first-trimester pregnancies with documented fetal heart activity, the spontaneous miscarriage rate is low.
- Maternal obesity (BMI >29.9 kg/m(2)) is not associated with an increased risk of spontaneous miscarriage.
- Body composition does not appear to be a significant factor in early pregnancy loss in this cohort.
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