What role does pituitary gonadotrophins play during follicular and ovulatory phases of menstrual cycle ? Explain the shifts in steroidal secetions .

Explanation

Hormonal control of follicular phase:
FSH of pituitary hormone transforms the primary follicle into Graafian follicle. FSH stimulates follicular cells of Graafian follicle to secrete estrogens. . Estrogens cause proliferation of endometrium which thickens and becomes more vascular and glandular.
Hormonal control of ovulatory phase: Estrogens stimulates pituitary gland to secrete LH. LH surge causes ovulation from the ovary on 14th day of menstrual cycle. into corpus luteum by luteinisation inside the ovary. LH also stimulates corpus luteum to secrete progesterone hormone to help in implantation, placentation and maintenance of pregnancy.