Question

During menstrual cycle the cyclical changes takes place in

• A. Endometrium
• B. Myometrium
• C. Perimetrium
• D. Corpus luteum

Answer 1

The correct option is A Endometrium

• During the menstrual cycle, the cyclical changes take place in the endometrium.
• In the proliferative phase, the endometrial cells in the uterus proliferate in preparation for a possible pregnancy. This growth is stimulated by oestrogen from the growing follicle (ovum, egg) in the ovary before ovulation causing the thickness of the endometrium to increase 3-5 fold.
• The secretory phase of the endometrium occurs after ovulation. In this phase, the cells in the endometrium become more complex in preparation for implantation of the embryo.
• This is due to stimulation from progesterone which is secreted by the corpus luteum in the ovary.
• The secretory phase of the endometrium corresponds to the luteal phase of the ovarian cycle when the corpus luteum is functioning in the ovary.
• Progesterone maintains the integrity of the endometrium and when pregnancy does not occur the progesterone level falls causing the endometrium to be shed as the menstrual period.
• So, the correct answer is option A.