Background and aims
Maternal overweight and obesity are associated with increased breastfeeding difficulties. We aimed to examine the influence, if any, of maternal body mass index (BMI), and of breast and nipple anatomic variations, upon breastfeeding difficulties and breastfeeding duration.
Methods
This a prospective, observational study in 109 breastfeeding mothers of full term newborns. Healthy women were classified as underweight, normal weight, overweight and obese using the WHO definitions. Demographic and breast anthropometrics assessments were recorded after delivery. Breastfeeding duration was assessed by phone interview at 3, 6 or 24 months post-delivery.
Results
The four pre-pregnancy BMI groups included 12 underweight, 59 normal weight, 20 overweight and 18 obese women. The higher the BMI, the larger the breast (p=0.005). In univariate regression, nipple diameter correlated significantly with breast size (R2=5.7%, p=0.014). A total of 14 participants were lost to follow up in terms of exclusive breastfeeding (table 1). Follow up on the remaining mothers showed that exclusive breastfeeding at 6 months of age (BF-6) was significantly negatively associated with breast size (p=0.025 by ANOVA with Bonferoni correction). In backward logistic regression analysis we found that (1) the higher the BMI, the lower the likelihood of BF-6 (odds ratio (OR) = 0.88, 95% CI, 0.79-0.99); (2) the higher the birth order, the higher the likelihood of BF-6 (OR = 3.36, 95% CI, 1.44-7.83).
Conclusions
We concluded that large breast size and to a lesser extend high pre-pregnancy BMI have a negative impact on breastfeeding initiation and duration.

BREASTFEEDING DIFFICULTIES, BREASTFEEDING DURATION, AND MATERNAL BMI: ARE THEY RELATED?