Follikulaarfaasis

Follikulaarfaasis, also known as follicular phase, is the first half of the menstrual cycle, lasting approximately 14 days. It begins on the first day of menstruation and ends with the release of an egg from the ovary, known as ovulation. During this phase, the follicles in the ovaries grow and mature, preparing for ovulation. The hormone estrogen plays a crucial role in this process, stimulating the growth of the follicles and the thickening of the uterine lining, known as the endometrium. As the follicles grow, they produce more estrogen, which in turn inhibits the release of follicle-stimulating hormone (FSH) from the pituitary gland, creating a negative feedback loop. This phase is characterized by a decrease in the production of luteinizing hormone (LH), which is responsible for triggering ovulation. The follicular phase is essential for the preparation of the reproductive system for potential fertilization and pregnancy. If fertilization does not occur, the follicular phase transitions into the luteal phase, where the corpus luteum forms and prepares for the next menstrual cycle.