Male infertility

Reproductive system

Female reproductive system

Ovaries

Ovaries are small, oblong organs that are just below the fallopian tubes on each side of the uterus. At birth, the ovaries contain about half a million immature eggs, and of those only a fraction develop into mature eggs during a woman’s lifetime.

Fallopian tubes

Although the fallopian tube may appear to be a simple organ, it is in fact rather complex. It is nearly one-half inch wide at its open end, which is close to the ovary. The tube narrows to the size of a pencil tip near the uterus. Fallopian tubes support the female’s egg and male sperm throughout the fertilization process.

Fallopian tubes are responsible for:

Picking up a newly released egg.
Providing nutrients and movement for the egg.
Transporting sperm to the egg.
Sustaining an environment for fertilization.
Moving a fertilized egg into the uterus.

Uterus

The uterus is the hollow, pear-shaped organ located in the low center of a woman’s pelvis. It protects, develops and nourishes the fetus until birth. Often the uterus is referred to as the womb.

Normal female reproductive physiology

The hypothalamus regulates the hormonal activity of the pituitary gland by secreting gonadotropin-releasing hormone (GnRH). This hormone controls the production of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary.

Beginning on the first day of menstruation (day one of a woman’s cycle), the body starts to make and release increasing amounts of FSH. This hormone, produced by the pituitary gland at the base of the brain, causes the follicles to grow and produce estrogen. The egg also begins to mature at this time. During the average cycle, on day 14, the pituitary gland releases a burst of another hormone called LH; this is referred to as the LH surge. LH stimulates ovulation (the release of a mature egg from the follicle and the ovary). As the egg travels through the fallopian tube, levels of another female hormone (progesterone) start to increase.

If there are sperm present in the fallopian tube, the egg may be fertilized and the resulting embryo will pass through the fallopian tube and enter the uterus, where it will implant and grow into a baby. If the egg is not fertilized, it will not implant and menstruation (the shedding of the lining of the uterus) will begin.