Infertility Health Article

Definition

Infertility is the failure to conceive a pregnancy after attempting for at least one full year. In primary infertility, pregnancy has never occurred. In secondary infertility, one or both members of the couple have previously conceived, but are unable to conceive again after a full year of attempting.

Description

Currently, in the United States, about one in five couples struggles with infertility at any given time. Infertility has increased as a problem over the last 30 years. Some studies assign the blame for this increase on social phenomena, including the tendency for marriage to occur at a later age. Fertility in women decreases with increasing age, as illustrated by the following statistics. In one year of trying to become pregnant:

• Infertility in women at age 20 is 4%.
• Infertility in women at age 30 is 7%.
• Infertility in women at age 35 is 12%.
• Infertility in women over the age of 40 is 75%.

Many individuals have multiple sexual partners before marriage. This increase in numbers of sexual partners has led to a rise in sexually transmitted diseases. Scarring from these infections, especially from pelvic inflammatory disease (PID, a serious infection of the female reproductive organs, most commonly caused by chlamydia and gonorrhea), seems to be partially responsible for increases in infertility. Furthermore, use of some forms of a contraceptive called the intrauterine device (IUD) contributed to an increased rate of pelvic inflammatory disease. However, the newer IUDs do not cause infections.

To understand issues of infertility, it is first necessary to understand the basics of human reproduction. Fertilization occurs when a sperm from the male merges with an egg (ovum) from the female, creating a zygote that contains genetic material (DNA) from both the father and the mother. If pregnancy is then established, the zygote will develop into an embryo, then a fetus, and ultimately a baby will be born.

The male contribution to fertilization and the establishment of pregnancy is the sperm. Sperm are small cells that carry the father's genetic material, which is contained within the oval head of the sperm. The sperm are mixed into a fluid called semen that is discharged from the penis during sexual intercourse. The whip-like tail of sperm allows them to swim up the female reproductive tract in search of an egg (ovum).

The female makes many contributions to fertilization and the establishment of pregnancy. The ovum is the cell that carries the mother's genetic material; ova (plural of ovum) develop within the ovaries. Once a month, a single mature ovum is produced, and leaves the ovary in a process called ovulation. This ovum enters a tube leading to the uterus (the fallopian tube). If fertilization is to occur, the ovum must encounter the sperm in the fallopian tube.

When fertilization occurs, the resulting cell is called a zygote. This single cell will multiply within the fallopian tube, and the resulting cluster of cells, a blastocyst, will then move into the womb (uterus). The uterine lining (endometrium) has been preparing itself to receive a pregnancy by growing thicker. If the blastocyst successfully reaches the inside of the uterus and attaches itself to the wall of the uterus, then pregnancy has been achieved.

Causes and symptoms

Unlike most medical problems, infertility is an issue requiring the careful evaluation of two separate individuals, as well as an evaluation of their interactions with each other. In about 3–4% of couples, no cause for their infertility will be discovered.

The main factors involved in causing infertility, ranging from the most to the least common, include:

• male problems: 30-40%
• ovulation problems: 10-15%
• pelvic disease: 30-40%
• cervical factors: 10-15%
• undiagnosed: 5-10%

Diagnosis

Diagnosis of infertility involves examination of both male and female partners.