Predictors of Lactogenesis II
Condition: Breastfeeding
Study type: Observational

Summary: 
      The purpose of this study is to investigate what proportion of obese women will have a
      self-reported delay in lactogenesis II ("breastmilk coming in") compared to women with a
      normal weight. We hypothesize that obese women will have an absolute 20% increase in delayed
      lactogenesis II.

      We will compare two group of women for delayed lactogenesis II, one group with obese women
      (BMI>30) and one group of women with a normal weight (BMI<30).

      The secondary objective is to assess what other factors influence the self-reported delayed
      lactogenesis II.
    

Detailed description: 
      Lactogenesis I occurs during pregnancy (midpregnancy and beyond), when the mammary glands
      becomes sufficiently differentiated to secrete small quantities of specific milk components.
      Lactogenesis II is defined as the onset of plentiful milk secretion and typically occurs
      between 30-40 hours post delivery. It is typically described by women as a sense of fullness
      and leakage of milk which is subjectively reported between 50-73 hours post delivery. The
      incidence of delayed lactogenesis II ranges from 17-44%.

      The risk of neonatal weight loss is up to 7 times greater for exclusively breastfed infants
      of women who experience delayed lactogenesis II as compared to women who experience typical
      onset lactogenesisII. In a qualitative study of 114 lactating women, increasing BMI was
      significantly associated with maternal perceptions of delayed onset of lactogenesis II.

      The United States Breastfeeding Committee supports exclusive breastfeeding for the first 6
      months of life because it "may exert a small but positive influence in reducing the risk of
      obesity in childhood and later in life…" Breastfeeding has also been associated with
      decreased risk of maternal morbidities such as type 2 diabetes, subclinical cardiovascular
      disease and less abdominal visceral adiposity. Given that prolonged breastfeeding improves
      the overall health of the mother infant dyad, it is critical to obtain a better understanding
      of those factors predictive of successful breastfeeding outcomes.

      At University of South Florida our clinics serve an ethnically diverse population which would
      benefit from directed efforts at improving breastfeeding. Before we can undertake such a plan
      we need to assess the contemporary factors impacting lactogenesis.

      We plan to prospectively enroll 186 pregnant women into a protocol to examine factors
      associated with delayed lactogenesis. Ninety-three women will have a BMI of 30 or higher at
      the time of delivery and the other 93 women will have a BMI ≤ 29 at the time of delivery.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        We plan to prospectively enroll 186 pregnant women into a protocol to examine factors
        associated with delayed lactogenesis. Ninety-three women will have a BMI of 30 or higher at
        the time of delivery and the other 93 women will have a BMI ≤ 29 at the time of delivery.
      
Keywords: Breastmilk; Lactogenesis; Obesity