What is Menstrual Cycle?


In females, the eggs are present in Germinal layer of ovary. Actually the eggs are formed in fetal life in yolk sac and then transmigrated to ovary during its development. There the eggs remain dormant till puberty.

At birth, the ovaries contain approximately 4 million immature Premordial Follicles. Their sizes range from 0.25 to 1 mm. Each primordial follicle contains an egg in its core surrounded by layers of stromal cells. The stromal cells produce hormones- Estrogen and Progesterone.

From Menarche (beginning of menses) at puberty until Menopause (Cessation of menses) every month approximately 1000 primordial follicles begin to develop out of which 20 are recruited for further development. The best amongst them takes the lead and mature into Graffian follicle of about 1 cm size.

At middle of the cycle around 14th day, the mature follicle ruptures to release the egg free into the peritoneal cavity. This process is called as Ovulation. This free egg along with its surrounding stromal cells is picked up by the fallopian tubes through the negative suction pressure.

After ovulation the released egg undergoes the process of sexual/reduction division called Meiosis and forms Primary ovarian follicle and primary polar body which contains 23 chromosomes each instead of 46. Since they contain half the number of inherited chromosome, they are called haploid cells. The life of this egg is approximately 24 hours.

During this period of survival, the haploid egg and sperm may fertilize at the ampullary part of fallopian tube to form a single diploid zygote that contain normal number of 46 chromosomes. This zygote then travels to the uterine cavity for implantation and further development into embryo.


To provide initial nourishment to the developing zygote, the inner endometrial lining of the uterus grows approximately 1.5 cm thick under the influence of ovarian hormones estrogen and progesterone till the fetus forms its placenta.

The remnant of ovarian Graffian follicle undergoes process of leutinization to form the corpus luteum that produces estrogen and progesterone to support pregnancy. The life of corpus luteum is 10 days.

The embryo helps own survival by producing Human Chorionic Gonadotropin, that prolongs the life of corpus luteum by 3 months so that it can produce required hormones to support pregnancy till the placenta is formed and takes over.

In the absence of pregnancy and HCG hormone, the corpus luteum degenerates into corpus albicans, that do not produce progesterone hormone and hence the inner endometrial lining sheds in the form of menstrual blood. This is nature’s way to form a new endometrial lining for newer egg.

What is a normal menstrual cycle?

A normal menstrual cycle is of 21 to 35 days duration with an average total blood loss of 50 – 80 ml lasting 2 to 6 days.  The woman may experience little pain and discomfort during menses since almost 1.5 cm thick layer has to expel through a cervical os of 1 mm.


Facts & Beliefs associated with menstrual cycle?

  • Is Menstrual blood dirty?

Ans – Certainly not. In fact, it is rich in nutrients and oxygen to provide initial nourishment to the embryo. It is a pure blood.

  • In some religions, the menstruating woman is isolated from rest of the family, abandoned to visit temple or water holy plant Tulsi etc.?

Ans – In ancient times, the women did not enjoy the equal status in society. Our socialist ancestors were very sensitive towards empowerment of women against the prevailing customs.

Many women experience discomfort and pain during menses.  So, in order to provide them due care these rituals were propagated.

  • The women were refused to visit temple or water Tulsi so that they don’t have to get up early in morning.
  • They were isolated so that Husband does not force them for sexual relationship.
  • Their food was separately prepared to offer them fresh food rather than leftover.

So, it is advisable not to take medicines to delay the menstrual cycle on account of religious customs.

  • Homemade sanitary pads are better than those ready to use in market?

Ans- Ready to use sanitary pads available in market from good company is safe and simple. On the contrary, the home made pads when not cleaned, dried and ironed properly may harbor infection.


The information is shared to create awareness towards Pregnancy and Childcare to reduce maternal and child deaths. Atmost care has been taken by the author to include the verified information from authentic sources. However, kindly discuss the same with your health care provider before implementation.