What event concludes the third stage of labor?

The third stage of labor is defined as the period following the birth of the baby, focused on the delivery of the placenta. This stage typically begins immediately after the infant is born and involves the separation and expulsion of the placenta from the uterine wall. The successful completion of this stage is marked by the delivery of the placenta, which is crucial for ensuring that the uterus contracts properly to reduce the risk of postpartum hemorrhage.

In this context, the other options do not represent the conclusion of the third stage of labor. The release of milk pertains to lactation and occurs postpartum after hormonal changes, while the infant's birth marks the end of the second stage of labor. The contraction of the cervix primarily occurs during the first and second stages as the body prepares for delivery and helps facilitate the passage of the infant. Thus, the delivery of the placenta signifies the end of labor’s active phases and is an essential aspect of maternal care during this period.