Causes of Female Infertility

The female reproductive system is a very delicate system. Some major causes of female infertility are problems in the

• Ovaries
• Fallopian Tube
• Uterus
• Advancing Age
• Endometriosis
• PCOS

Ovaries

Every woman is born with a lifetime's supply of eggs. The eggs are stored in the ovaries. The process by which the ovaries release a mature egg each month is called ovulation. Abnormalities in ovulation show up as longer or shorter menstrual periods, no periods for stretches of a few months and in some cases menstruation stops prematurely. The cause of these can be determined by blood tests to determine the levels of the various hormones active in the menstrual cycle. The main hormones checked are FSH (Follicle Stimulating Hormone), LH (Luteinizing Hormone), prolactin.

Fallopian Tubes

What are the fallopian tubes?

The fallopian tubes are the two passageways from the ovaries to either side of the uterus. The eggs released by the ovary is picked up by the fimbrian end of the fallopian tubes. Fertilization occurs here and the embryo makes its way down the fallopian tube into the uterus. The fallopian tubes help in the movement of the egg and embryo towards the uterus and also nourishes them during the time they spend in the fallopian tube.

Diseases of the fallopian tubes

Abnormalities in the fallopian tube are one of the leading causes of female infertility. This is mainly caused by PID (Pelvic Inflammatory Disease) which can be caused by -

• Sexually transmitted diseases (e.g. Gonorrhea, Chlamydia)
• Tuberculosis
• Post-operative pelvic infection (e.g. perforated appendix, ovarian cysts)
• Infection after childbirth, miscarriage, termination of pregnancy (MTP) or IUD (Intrauterine Device) insertion

PID (Pelvic Inflammatory Disease) affects the tubes in two ways -

• Causes blockages in the fallopian tubes
• Causes adhesions on the surface of the tubes which affects the functioning of the tubes.

Endometriosis can also cause peritubal adhesions and thus leading on to tubal factor of infertility.

Uterus

The uterus plays a critical role during pregnancy. Women with uterine abnormalities may be able to conceive normally but have trouble carrying the pregnancy to full term. Some common uterine conditions are the presence of adhesions, congenital abnormalities and endometrial polyps.

Fertility and Age

Advancements in fertility science has vastly improved the chances of women over 35 getting pregnant. A healthy, active woman has a high chance of giving birth to a healthy baby. Advancing age does bring its set of issues that have to be dealt with.

A woman is born with a fixed number of eggs and with increasing age, the reserve of eggs starts depleting. As this number decreases the chances of getting pregnant also decreases progressively. The number of eggs remaining in the ovary can be determined using blood tests. High levels of FSH (Follicle Stimulating Hormone) and low levels of inhibin B indicate a low number of eggs in the ovaries.

Treatment options like IVF increase the chances of a successful pregnancy outcome. Most clinics have an upper limit on the age beyond which they do not accept the woman's eggs for IVF. Donor eggs can be used in cases where the woman's own eggs are not found to be suitable.

Additional care to screen for chormosomal abnormalities in the eggs can be used to prevent the increased risk of conditions like Down's syndrome.

Endometriosis

Endometriosis is a condition in which the endometrial tissue, typically found inside the uterus, starts growing outside the uterus. Normally, the endometrium grows during the menstrual cycle under the influence of the hormones estrogen and progesterone in the uterus. In the absence of pregnancy the entire tissue is shed at the end of the menstrual cycle. However, if the growth is outside the uterus, the bleeding occurs there. This causes fibrosis and adhesions around that area leading to pain and impaired fallopian tube motility. The quality of egg released also gets reduced in endometriosis.

PCOS (Polycystic Ovarian Syndrome) or PCOD or or the Stein-Leventhal syndrome

PCOS (or PCOD) is a condition where multiple follicles rather than growing to its full extent gets arrested in its growth and so appear as multiple small cysts (Fluid-filled sacs) in the ovaries. This arrest in growth of follicles occur due to the increase in the presence of androgen hormones in the ovary which arrest its further maturation. The classical symptoms of PCOS include irregular or absent menstrual cycles, obesity, insulin resistance and hirsutism (more hair on the face and body). This lack of ovulation and the abormal presence of hormones can lead to infertility.

The symptoms become worse as the person puts on weight. Increase in weight leads to imbalance in body hormones which leads to increased androgen production which is detrimental to the eggs in the ovary. Just a 5% decrease in the present body weight can significantly improve ovulation.