What significant change occurs in the cervix just before delivery?

The significant change that occurs in the cervix just before delivery is full dilation of the cervix. This process is crucial for facilitating the passage of the baby through the birth canal during labor. As labor progresses, the cervix undergoes a series of changes to become fully dilated, usually to about 10 centimeters, allowing the fetus to move from the uterus to the vaginal canal for birth.

During this stage, the softening and effacement of the cervix take place, which prepares it for dilation. The complete dilation is a key indicator that the body is ready for the second stage of labor, where the baby is pushed through the birth canal. This physiological transformation is essential for the safe delivery of the baby, marking the transition from pregnancy to childbirth.

While the other choices relate to changes that can occur in the cervix during pregnancy or labor, they do not represent the final critical stage that ensures delivery is imminent. For instance, thickening of cervical mucus usually occurs earlier during pregnancy and functions as a protective mechanism, while complete closure of the cervix happens in a non-labor state. Inflammation of the cervix can occur due to various conditions or infections but is not a significant change associated with the process leading up to delivery.