Final answer:
The claim that cervical softening due to increased vasculature occurs at 4-5 weeks of pregnancy is false. Cervical softening and dilation are typically associated with labor, which occurs much later in pregnancy.
Step-by-step explanation:
The statement that the softening of the cervix due to increased vasculature occurs at 4-5 weeks of pregnancy is false. During the early stages of pregnancy, there are indeed physiological changes in the cervix due to the increased blood flow, but the significant softening and dilation of the cervix are mainly associated with the onset of labor. The process of cervical dilation is one of the stages of childbirth, where the cervix thins (effacement) and dilates to about 10 cm to allow the baby to pass through.
In pregnancy, changes such as placentation, the formation of the placenta, are indeed underway by weeks 14-16, and the cervix is undergoing preparation for labor throughout the pregnancy. However, the specific change to the cervical structure referred to in the context of labor occurs much later in pregnancy, typically during the birthing process itself. Polyspermy, penetration of an oocyte by more than one sperm, is unrelated to the changes in the cervix.