Infertility in women can vary from easily resolved to extremely complicated issues. If any aspect of the ovulation process is interrupted, infertility can result.
Chronic issues of the reproductive tract can also be problematic. In many cases, infertility develops because of anovulation, when ovulation does not occur. Additionally, it may be the result of eggs that are low in quality or quantity. Additionally, the cause could be anatomical abnormalities that develop congenitally or because of previous procedures or problems. Here’s a look at ten causes of infertility.
1. Polycystic Ovarian Syndrome
Polycystic Ovarian Syndrome (PCOS) is one of the most common causes of infertility in women. About 10% of women who are considered to be of "reproductive age" have PCOS, and infertility is a frequent complication. PCOS is a hormonal issue characterized by a decreased production of follicle-stimulating hormone (FSH) and an increased production of testosterone. As a result, the ovarian follicles are inadequate and develop immature eggs.
2. Pelvic Inflammatory Disease
Pelvic Inflammatory Disease (PID) is an infection of the reproductive tract in women. This infection develops from bacteria from sexually transmitted infections (particularly gonorrhea or chlamydia), although the Mayo Clinic reports "bacteria can enter your reproductive tract anytime the normal barrier created by the cervix is disturbed." This includes childbirth, an abortion, or a miscarriage. Symptoms may be severe or nonexistent, but either way, PID can create scarring or fallopian abscesses, leading to infertility after recurrent infections or without treatment.
3. Fallopian Tube Abnormalities
Abnormalities of the fallopian tubes may develop because of congenitally malformed fallopian tubes, ectopic pregnancies, or infections that cause scar tissue between normally unconnected reproductive structures. Additionally, "hydrosalpinx" is a condition in which the ends of the tubes seal shut, creating a buildup of fluid inside the tubes. When the fallopian tubes are blocked off, eggs cannot pass from the ovaries to the uterus.
4. Hormonal Imbalance
When the hypothalamus fails to secrete hormones needed to stimulate the pituitary gland, the pituitary becomes incapable of producing hormones to initiate ovulation. Excess levels of prolactin can decrease these hormones, leading to anovulation. Additionally, insufficient progesterone levels can prevent the uterine lining from thickening in preparation for carrying a fetus.
5. Reproductive Scarring
Abdominal surgery can create scar tissue impeding the natural movement of the reproductive organs and causing infertility. Additionally, some procedures performed vaginally may weaken or scar the cervix, which can cause a barrier from the other direction. Abdominal, ovarian, or pelvic surgeries may also be problematic.
Endometriosis is a condition in which the lining of the uterus (the endometrium) begins growing outside the uterus. Even when it does not result in infertility, it may cause other pregnancy-related complications. Research suggests the severity of the disease determines the chances of infertility.
7. Chronic Disease
Serious and chronic issues like kidney disease, adrenal gland disorders, diabetes, thyroid disorders, high blood pressure, and even certain urinary tract infections can result in infertility. Women with active inflammatory bowel diseases (such as ulcerative colitis or Crohn’s disease) may have more difficulty becoming pregnant. Poor eating habits or an unhealthy weight makes this particularly true. Keeping these issues under control and seeking proper treatment may be helpful. Fibroids in the uterus, ovarian cysts, and, very rarely, pelvic inflammation as a result of appendicitis can also be causes of infertility in women.
8. Age-Related Infertility
As women age, fertility decreases and the probability of miscarriage increases. The ovaries of older women may have greater difficulty releasing their remaining eggs or have low-quality eggs. Hormones in charge of promoting egg development, initiating ovulation, and sustaining pregnancy are greatly reduced by age 40. Additionally, women are born with all their eggs, which deteriorate as they age. Eggs become harder, making it difficult for sperm to penetrate the shell, while other eggs may contain genetic defects that cause miscarriage or prevent fertilization.
9. Environmental Factors
Studies suggest poor diet, stress, too much or not enough exercise, smoking cigarettes, being over- or underweight, the use of certain illicit substances, steroids, excessive alcohol consumption, lead exposure, repeated exposure to radiation, chemotherapy, and various toxins and chemicals may all impact fertility to varying degrees. Certain medications (antibiotics, hormones, antidepressants, and some NSAIDS) may cause temporary infertility.
10. Less Common Causes
Obviously, experts have not solved every fertility mystery. In some cases, for unknown reasons, ovarian follicles may fail to rupture. As a result, the egg fails to erupt and simply remains in the ovary, where it cannot be fertilized. Additionally, cervical mucus can play a role. Normally thick mucus thins out during ovulation to facilitate sperm movement. If this doesn’t happen, it becomes much more difficult for sperm to travel into the fallopian tubes. Rarely, this mucus can contain antibodies that kill necessary proteins in the sperm, debilitating it before it can unite with an egg (sometimes referred to as a sperm allergy).