Etonogestrel Implant in the Postpartum Period and its Impact on Biochemical Markers in Secretory Activation: A Pilot Study.

Background: Secretory activation is characterized biochemically in human milk by a fall in sodium concentration, an increase in potassium concentration, and a decreased sodium to potassium ratio. These markers can be used to identify a delay in secretory activation which can result from hormonal birth control.

Research Aim: To evaluate if the insertion of the Etonogestrel implant early in the postpartum period would delay the time to secretory activation as measured by biochemical markers.