IBCLC Practice Exam 2025 – Complete Preparation Guide

The correct answer highlights the three primary hormones involved in the process of lactogenesis II, or secretory activation, which occurs after birth. Prolactin is crucial for milk production; it stimulates the mammary glands to produce milk after delivery. Estrogen plays an important role during pregnancy to prepare the breast tissues for lactation by promoting the development of milk ducts and alveoli. After giving birth, the level of estrogen drops, which allows prolactin to take on a more dominant role in milk synthesis. Oxytocin is essential for milk ejection; it causes the muscles around the alveoli to contract and release milk from the breast when the infant suckles.

Understanding the roles of these hormones is critical for lactation consultants, as they provide insight into the physiological changes that occur during breastfeeding. While other hormones play roles in metabolic processes or appetite regulation, they are not primarily responsible for initiating and sustaining milk production in the context of lactogenesis II.