s most important functions is to cause the endometrium to secrete special proteins during the second half of the menstrual cycle, preparing it to receive and nourish an implanted fertilized egg. If
implantation does not occur, estrogen and progesterone
levels drop, the endometrium breaks down and menstruation occurs.
2. Role in Pregnancy: If pregnancy occurs, progesterone is produced in the placenta, and levels remain elevated throughout the pregnancy.