Question

Which layer of the uterus undergoes cyclic changes during the menstrual cycle?
A. Myometrium
B. Endometrium
C. Perimetrium
D. All of the above

Answer 1

A menstrual cycle can be defined as the regular natural change that occurs in the female reproductive system that is responsible for the possibility of pregnancy. It involves shedding of the innermost lining of the uterus.

Complete step by step answer: The menstrual cycle is described by the ovarian and uterine cycle. The uterine cycle describes the changes in the endometrial lining of the uterus, while the ovarian cycle describes the changes in the follicles of the human ovary. Menstruation is simply the shedding of the endometrial lining. Both ovarian and uterine cycles are divided into three phases. The uterine cycle consists of menstruation, proliferative phase and secretory phase. The ovarian cycle involves the follicular phase, ovulation and the luteal phase. The average menstrual cycle is 28 days. The variability of the lengths of the menstrual cycle is highest for the women under the age of 25 years and is lowest (most regular) at 25-29 years. The variability increases slightly for 40 to 44 aged women. The first period which is called menarche occurs in the teenage. Some women with neurological conditions experience the increased activity of their conditions about the same timings during each menstrual cycle. Researches have indicated that women have a significantly higher chance of anterior cruciate ligament injuries in the preovulatory stage compared to the postovulatory phase.
Hence, the correct answer is option B.

Note: The average age of menarche is 12-15 years. The average age of menarche is approx. 12.5 years in the U.S, 12.7 in Canada, 12.9 in the U.K and 13.1 years in Iceland. Factors such as genetics, diet and overall health can affect the timing of the onset.