Causes of Infertility
Infertility is defined as being unable to conceive after one year of unprotected sex. Women who don’t have regular menstrual cycles or are older than 35 and have not conceived after 6 months of trying, should be evaluated.
Infertility can result during any one of the stages required to get pregnant:
- First, the woman’s body releases an egg from her ovaries- ovulation.
- Second, a man’s sperm must be capable of fertilizing the egg.
- Third, you need to have regular intercourse during the woman’s fertile periods.
- Fourth, the fertilized egg must travel through the fallopian tubes and land in the uterus where it implants in the uterine wall. The fallopian tubes must be open and you must have a normal uterus.
How common is infertility?
About 6% of married women ages 15-44 in the US are unable to get pregnant after one year of unprotected sex. About 12% of women in that age group have difficulty getting pregnant or carrying to term “impaired fecundity.”
What causes infertility in women?
The failure to ovulate is the most common cause of infertility, which affects about 40% of women with infertility. A failure to ovulate can result from:
- Primary Ovary Insufficiency (POI) (also called Primary Ovarian Failure or premature menopause) is a condition in which a woman’s ovaries stop working before the age of 40. An autoimmune disorder is common and causes the body to attack ovarian tissues, resulting in the premature loss of eggs and an inability to produce eggs. It can be due to genetic abnormalities or damage from chemotherapy and radiation. It is also caused by thyroid, adrenal and hormone disorders.
- Polycystic Ovary Syndrome (PCOS) is a common cause of female infertility. It is a condition that involves changes in the hypothalamus, pituitary and ovaries which results in a hormonal imbalance that negatively affects ovulation. Researchers estimate that 5% to 10% of women in the United States have PCOS. The exact cause of PCOS is unknown, but current research suggests that a combination of genetic and environmental factors leads to the disease.
Fallopian Tube Disease
Changes in the structure of the female reproductive organs may affect the release of the egg after ovulation or interrupt the egg’s movement through the fallopian tubes.
Tubal disease affects about 25% of infertile women. Blockage of the tubes may be due to adhesions or complete blockage. This may be caused by infection, abdominal disease, previous surgeries, and ectopic pregnancy. If the fallopian tubes are damaged, the egg may fail to reach the uterus to be fertilized. In addition, some women are born with blockages in their fallopian tubes.
Diseases and conditions of the Uterus
At least 10% of female infertility is caused by an abnormal uterus.
- Endometriosis occurs when the cells that normally line the uterine cavity, called endometrium, grow outside the uterus instead. Research has found a link between infertility and endometriosis. Studies show that between 25% and 50% of infertile woman have endometriosis, and between 30% and 40% of women with endometriosis are infertile. Scientists do not know the exact cause of infertility in women with endometriosis.
- Uterine Fibroids are growths that appear within and around the wall of the uterus. Most women with fibroids do not have problems with fertility and can get pregnant. However, some women with fibroids may not be able to get pregnant naturally or may have multiple miscarriages or preterm labor. Fibroids often contribute to infertility and are found in 5% to 10% of infertile women.
- Polyps are noncancerous growths on the inside surface of the uterus that can interfere with the function of the uterus and make it difficult for a woman to remain pregnant after conception. Surgical removal of the polyps can increase the chances for a woman to get pregnant.
- Uterine scarring from previous injuries or surgery. Scarring may increase the risk of miscarriage and infertility.
- Congenital defects that cause an unusually shaped uterus can affect a woman’s ability to remain pregnant after conception.
- Chronic infections in the cervix can also reduce the amount or quality of cervical mucus, the sticky or slippery substance that collects on the cervix and in the vagina. Reduced amount or quality of cervical mucus can make it difficult for women to get pregnant.
At Virginia Fertility Associates, in Richmond, VA we have the knowledge, skills and techniques to answer your questions and offer solutions to your infertility. If you are concerned, please schedule a consultation with our team so we can help you realize your dream of parenthood.