Relationship between maternal body mass index with the onset of breastfeeding and its associated problems: an online survey

Obesity is a worldwide public health problem that demands significant attention. Several studies have found that maternal obesity has a negative effect on the duration of breastfeeding and delayed lactogenesis. The World Health Organization has classified Body Max Index (BMI) as normal weight (normoweight) (BMI:18.5–24.9), overweight (BMI:25–29.9), obesity grade I (30.0–34.9), obesity grade II (BMI: 35.0–39.9) and obesity grade III (BMI ≥ 40.0). The objective of this study is to describe the relationship between maternal BMI and breastfeeding rates, as well as breastfeeding-associated problems and discomfort in women assisted by the Spanish Health System. To this end, a cross-sectional observational study aimed at women who have been mothers between 2013 and 2018 in Spain was developed. The data was collected through an online survey of 54 items that was distributed through lactation associations and postpartum support groups between March and June 2019. Five thousand eight hundred seventy one women answered the survey. In the data analysis, Crude Odds Ratios (OR) and Adjusted Odds Ratios (AOR) were calculated through a multivariate analysis through binary and multinomial regression. A linear relationship was observed between the highest BMI figures and the reduction of the probability of starting skin-to-skin contact (AOR for obesity type III of 0.51 [95% CI 0.32, 0.83]), breastfeeding in the first hour (AOR for obesity type III of 0.58 [95% CI 0.36, 0.94]), and exclusive breastfeeding to hospital discharge (AOR for obesity type III of 0.57 [95% CI 0.35, 0.94]), as compared to women with normoweight. Women with higher BMI are less likely to develop successful breastfeeding than women with normoweight.