Normal Reproductive Cycle and Fertility Evaluation

For a successful conception, it is extremely essential to understand the normal reproductive cycle of your body. Often, people are not aware of this concept. When they are not able to conceive, they take stress which leads to more complications. There are three stages of the normal reproductive cycle in women which are controlled by hormones present in her body. This cycle gets disturbed becoming irregular or stopping altogether when there is a hormonal imbalance, leading to the condition of infertility in women. The cycle is typically 28 days long. The stages of cyclic events in the female reproductive system are:

The Follicular Phase

This stage prepares the uterus for pregnancy. The brain has the control command for the reproductive cycle. It signals the hypothalamus to begin the production of follicle-stimulating hormone by the pituitary gland, which in turn leaves 20-30 active hormones in the ovaries. This number reduces with increasing age. The developing follicles produce oestrogen which thickens the lining of uterus, preparing to accept the sperm. Only one follicle gets mature during this stage.


Few days before ovulation, the sperm is allowed to pass through the cervix and uterus into the fallopian tubes where it can stay alive and wait for the female egg for fertilization for 2-3 days. Once the follicle develops, it releases the female reproductive hormone, estrogen. The single matured female follicle releases the egg into the ovary, which can fertilize now if it comes into contact with the waiting sperm, in the maximum time span of 24 hours. This fertilized egg is now called an embryo.

The Luteal Phase

Once the developed follicle has released the egg, the remaining part is called the corpus luteum, which releases a lot of progesterone now. The high levels of estrogen and progesterone present now inhibit the development of future follicles. The embryo travels through the fallopian tube, hatches and implants itself in the uterus. The embryonic cells released during hatching form the placenta or the sack where the baby is formed and nurtured during pregnancy and release HCG. The estrogen and progesterone continue to be released to support the pregnancy phase. The presence of HCG confirms a successful pregnancy test result.

If, however, fertilization has not taken place, the corpus luteum is not able to maintain the oestrogen and progesterone levels and the menstruation starts. The complete cycle begins again.

Fertility Evaluation

Tests are available for evaluation of fertility for both men and women. While major tests for men are around physical examination, sperm analysis and count, for women it includes physical examination, irregular menstrual cycle, ultrasound of ovaries, use of ovulation kits and blood test to determine the hormonal levels. The fallopian tubes are tested to see there is no blockage. Each area where the sperm and egg would pass through in the reproductive cycle is examined to see where the problem would lie, including X-ray and HSG test that can provide confidence to the couple wanting to conceive.