Final answer:
Estrogen induces changes in the ovaries and uterus to prepare the uterus for the reception of a fertilized egg.
Step-by-step explanation:
Estrogen induces changes in the ovaries and uterus to prepare the uterus for the reception of a fertilized egg. It inhibits the release of further FSH and LH, preventing the development of additional eggs and follicles. The high levels of estrogen also increase uterine tube contractions, decrease vaginal acidity, and thicken the endometrial lining in preparation for implantation.