International Board of Certified Lactation Consultant (IBCLC) Practice Exam

During Lactogenesis II, which typically occurs around 2-4 days postpartum, the composition of breast milk undergoes significant changes as it transitions from colostrum to mature milk. One of the key changes is a decrease in sodium content. In the early days after birth, colostrum is rich in various immunoglobulins and is specifically tailored to meet the newborn's needs, providing hydration and essential nutrients. As the lactating woman’s milk transitions into mature milk, there is an adaptive response for the milk to modify its composition based on the evolving needs of the infant. The decrease in sodium is important for maintaining the appropriate electrolyte balance within the milk. This reduction helps ensure that the milk isn't too concentrated with sodium, which is crucial for the health and development of the newborn, especially considering that newborns' renal systems are still maturing and are less capable of handling high sodium levels. Understanding these changes in milk composition during lactogenesis phases is essential for lactation consultants, as they often have to provide guidance on feeding practices, monitor infant weight gain, and address any concerns that may arise regarding breastfeeding.