A. Explain the following phases in the menstrual cycle of a human female:

(i) Menstrual phase

(ii) Follicular phase

(iii) Luteal phase

B. A proper understanding of menstrual cycle can help immensely in family planning. Do you agree with the statement? Provide reasons for your answer.

A. Menstrual phase: This phase is characterized by bleeding. Bleeding occurs due to breakdown of the soft tissue of endometrial lining of the uterus. The unfertilized egg and soft tissues are discharged in the bleeding. It lasts for 3 to 5 days.

Follicular phase: it is also known as proliferative Phase. In this phase the primary follicles in the ovary grow and matured and become Graafian follicle. The secretion of gonadotropins (LH and FSH) increases gradually during the follicular phase. It lasts for about 10 to 14 days.

Luteal phase: In this phase the ruptured follicle changes into corpus luteum in the ovary and it begins to secrete hormone progesterone. If ovum is not fertilized, the corpus luteum undergoes degeneration and this causes disintegration of endometrium leading to menstruation. It lasts 15 days to 28 days.

B. Yes, a proper understanding of menstrual cycle can help greatly in family planning. It is obvious from the menstrual cycle is that in between 10th to 17th day of the cycle, the chances of fertilization is high. If copulation is done during this period increases the chances of pregnancy is also high. So, abstaining from copulation during this period, pregnancy can be avoided.