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# Oral Histology and Embryology At puberty, the female begins to undergo regular monthly cycles controlled by the **hypothalamus** which secretes **gonadotropins**. These hormones, follicle-stimulating hormone (**FSH**) and luteinizing hormone (**LH**), stimulate and control cyclic changes in the o...

# Oral Histology and Embryology At puberty, the female begins to undergo regular monthly cycles controlled by the **hypothalamus** which secretes **gonadotropins**. These hormones, follicle-stimulating hormone (**FSH**) and luteinizing hormone (**LH**), stimulate and control cyclic changes in the ovary. At the beginning of each ovarian cycle, 15 to 20 follicles are stimulated to grow under the influence of FSH. Under normal conditions, only one of these follicles reaches full maturity, and only one oocyte is discharged; the others degenerate and become atretic. When a follicle becomes atretic, the oocyte and surrounding follicular cells degenerate and are replaced by connective tissue. ## Ovulation In the days immediately preceding ovulation, under influence of FSH and LH, the follicle grows rapidly to become a mature vesicular **graafian follicle**. The surface of the ovary begins to bulge locally. Before ovulation the oocyte and some cells of the ovarian wall detach and form a mound called the **cumulus oophorus** over the oocyte.