The Role of Maternal Prepregnancy Body Mass Index in Breastfeeding Outcomes: A Systematic Review

Background: The benefits of breastfeeding are well established in the literature. Barriers related to breastfeeding, such as maternal obesity, are also cited in the literature. Worldwide obesity rates in women of reproductive age are rising at an alarming pace. Previous research has attempted to study the relationship between maternal body mass index (BMI) and its effect on breastfeeding outcomes, but it is not clear what the role of maternal BMI category has on breastfeeding outcomes. Objectives: The objective of this review is to examine whether and how maternal BMI affects maternal breastfeeding outcomes such as intention, initiation, duration, and exclusivity. Methods: A systemic literature search through PubMed and Cumulative Index to Nursing and Allied Health Literature was conducted between January and May 2020, by using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A total of 23 relevant articles were retrieved. Results: Of the 23 studies that assessed the relationship between maternal BMI and breastfeeding intention and other outcomes, only 4 found no differences in breastfeeding outcomes across BMI categories. Higher than normal maternal prepregnancy BMI has been found to be associated with poorer breastfeeding outcomes. Overweight and obese women are less likely to intend to breastfeed and initiate breastfeeding. They also have shorter breastfeeding durations and are less likely to exclusively breastfeed for any period compared with normal weight women. Conclusions: Breastfeeding rates across all BMI categories do not meet the recommended guidelines established by the World Health Organization and other public health agencies, and overweight and obese women have poorer breastfeeding outcomes. Overweight and obese women need additional support to initiate breastfeeding, and to breastfeed longer and exclusively. Targeted and well-designed interventions should be implemented early in the perinatal period to support this vulnerable population.