Female Infertility: Causes and Treatment Options
Female-related infertility results from disease and anatomical problems, age, hormonal imbalances affecting the menstrual cycle, and/or other problems preventing conception or full-term pregnancy. Exposure to radiation or certain chemicals can cause infertility and women who smoke cigarettes can have enough nicotine in their cervical mucus to kill sperm. Others who have very low ratios of body fat to muscle from excessive exercise or eating disorders may have irregular periods and/or fail to ovulate. The most common female-related causes of infertility are:
- Tubal disease
- Pelvic adhesions
- Fibroids and Polyps
- Ovulatory dysfunction
Read the descriptions below to learn more about these causes of female infertility.
Age is the single most important factor affecting a woman’s fertility. As she matures, the chance for pregnancy decreases and the odds for miscarriage increase. At 25, a woman has a 25% of becoming pregnant during unprotected sexual intercourse. This percentage begins to decrease between the ages of 32 and 34. After that, the decline is steady so that the chance for pregnancy is only 5 to 10% per menstrual cycle after a woman reaches age 40.
Although older women may be more likely to experience scarring and blockages caused by endometriosis or other medical conditions, these are not significant contributors to infertility. Instead, infertility often is the result of age-related changes occurring in the reproductive hormones that stimulate egg development, trigger ovulation and support pregnancy. Perhaps most important, is depletion of a woman’s ovarian reserve – the eggs she is born with. During her reproductive years, some eggs never mature and others are released during her menstrual cycles. Those remaining age with her and the older she is, the more likely they are to have hard shells (zona pellucida) that keep sperm from penetrating or genetic defects that prevent fertilization or cause miscarriage. When the store of healthy eggs is depleted, menopause occurs.
Treatment Options for Age-Related Infertility
- Surgery – used to remove scar tissue and blockages from endometriosis and other conditions, or repair structural defects that prevent conception or pregnancy.
- Ovulation Induction (OI) – prescribed to regulate a menstrual cycle, stimulate the development of multiple eggs and/or trigger ovulation when irregular periods or ovulation problems occur. This may be used with insemination.
- In Vitro Fertilization (IVF) – recommended when conception is more likely to occur in vitro (outside the body) rather than in vivo (inside). With IVF, hormones usually are used to stimulate development of multiple eggs. Retrieved directly from the ovary, they are fertilized with the partner’s sperm and a limited number of embryos are transferred into the uterus.
- A laboratory-based procedure, intracytoplasmic sperm injection (ICSI), is used with IVF if the eggs have a hard shell and/or sperm problems are a factor. ICSI involves injecting a single sperm directly into the egg’s core. When IVF is an option and certain genetic abnormalities are suspected, preimplantation genetic diagnosis (PGD) – examination of a single cell from a developing embryo – can help identify affected embryos so they are not transferred.
- Egg donation – required when there are no eggs available or pregnancy is unlikely due to their number, age or condition. With donor IVF, eggs are retrieved from a young female whose follicles have been stimulated by fertility medications. If they are fertilized in the laboratory by the male partner’s sperm, the embryos are transferred into the recipient’s uterus, which has been prepared by fertility drugs.
Although IVF may be the best or only treatment for age-related infertility, outcomes decrease with age. This is supported by the 1988 national data reported to the Society for Assisted Reproductive Technology and the federal Centers for Disease Control. For women under 35, 32% of 1988 non-donor IVF cycles resulted in a live birth. Success was achieved by 26% of women age 35 to 37, 18% of those between 38 and 40, and 8% of those over 40. Most clinics require donor cycles beyond a certain age cut-off because of the poor chances for pregnancy with a woman’s own eggs.
2. Tubal Disease
The fallopian tubes carry eggs from the ovaries to the uterus. When tubes are blocked by scar tissue from endometriosis, surgery or infection, the egg and/or the sperm cannot travel through. If a fertilized egg is trapped in the fallopian tube, the result is an ectopic pregnancy, which must be treated with medication or surgery. Tubal problems include:
- Infections – sexually transmitted diseases, gonorrhea and chlamydia, often go unnoticed and untreated, causing pelvic inflammatory disease (PID). Serious infection can cause scar tissue and damage the cilia, or small hairs lining the tubes to help the eggs move through. Symptoms of sexually transmitted diseases include inflammation and abnormal discharge. PID can result in pelvic or abdominal pain and severe, untreated infection has been linked to cervical and other cancers, chronic hepatitis and cirrhosis of the liver.
- Hydrosalpinges – this condition is caused by a severe blockage – a hydrosalpinx – resulting from infection. It greatly reduces the chance of pregnancy without IVF because it stretches or distorts the fallopian tubes to the extent that they cannot be opened and/or repaired. When the tubes fill with fluid, there is a chance that it can leak back into the uterus. Because this fluid is toxic to embryos placed into the uterus during IVF, physicians often remove or surgically block the tubes before a cycle to improve embryo implantation rates.
- Endometriosis – tissue lining the uterus (endometrium) grows and thickens during a menstrual cycle to receive a fertilized egg (implantation). Without a pregnancy, the lining sheds and is discharged with blood during a menstrual period. Endometriosis occurs when this tissue grows outside the uterus and the shedding process deposits blood and tissue in the abdomen. As a result, scar tissue can form in the fallopian tubes, adhere to the ovaries and/or cause misalignment of the organs, preventing natural conception. Although some women have no discomfort even with severe endometriosis, others experience abnormal menstrual bleeding and pain, tenderness in the abdomen and pelvis, and/or painful intercourse.
- Tubal Ligation – a form of birth control, this surgical procedure involves tying, clamping off or burning the ends of the fallopian tubes so pregnancy cannot occur.
Treatment Options for Tubal Disease
- Medications – including antibiotics, can be effective in treating sexually transmitted diseases and PID. Early diagnosis and treatment are important to avoid further damage. Medications also may be prescribed for endometriosis, to help shrink the tissue that is blocking or distorting the organs.
- Surgery – may be an option for opening up and/or repairing tubal damage or blockages from infection, endometriosis, surgery or other factors. Surgery is the only way to reverse a tubal ligation, and it may be recommended to remove or block off the fallopian tubes prior to IVF for a patient with hydrosalpinges.
- In Vitro Fertilization (IVF) – required when blockages cannot be removed and/or tubal damage is so severe that it cannot be repaired, IVF is the recommended treatment. The tubes are bypassed during this procedure because the eggs are retrieved from the ovaries and fertilized outside of the body. The embryos are returned directly to the uterus for implantation.
3. Pelvic Adhesions
A thin layer of lubricated tissue, the peritoneum, covers the abdominal organs and allows them to slide against each other. Surgical procedures, infections and endometriosis can cause scar tissue – adhesions – that link two organs together. Adhesions on the ovaries can affect ovulation or block the fallopian tubes, keeping the egg and/or sperm from following their natural course. Adhesions inside the uterus can affect implantation. Although many women have adhesions without symptoms, they can cause severe menstrual cramps, abdominal tenderness, pelvic pain or pain during intercourse.
Treatment Options for Pelvic Adhesions
- Surgery – recommended for removing adhesions and/or repairing damage from infections, endometriosis, surgeries or other factors.
- In Vitro Fertilization (IVF) – required when adhesions are severe and cannot be removed, or damage is so severe that it cannot be repaired.
Fibroids and Polyps
Saline sonogram showing a polyp
These growths (fibromas, myomas and leiomyomas) are benign tumors made up of thread-like tissue that clumps together to form masses. Usually found inside the uterus, they affect implantation of the fertilized egg. Symptoms associated with fibroids – especially if they are large – include heavy bleeding, pain and abdominal pressure.
Treatment Options for Fibroids and Polyps
- Medication – although medications can shrink fibroids in some cases, the result is not permanent. Instead, they can only temporarily reduce symptoms, delay surgery or shrink the fibroid enough to allow for a less invasive surgical procedure.
- Surgery – required for removal of fibroids and polyps if they are large enough and are affecting fertilization and/or embryo implantation.
4. Ovulatory Dysfunction
Ovulatory dysfunction results from congenital defects, hormonal deficiencies and/or the aging process. Some women don’t have menstrual periods while others menstruate but don’t ovulate. Women with amenorrhea have never had a period or had irregular periods that stopped prematurely. With anovulation, eggs aren’t released from the follicles and oligo-ovulation is characterized by longer cycles and infrequent ovulation. Other forms of ovulatory dysfunction, called luteal phase defects, occur when a woman has a menstrual cycle and is ovulating, but the cycle is too short for the uterine lining to thicken properly. Common forms of ovulatory dysfunction include:
- Premature Ovarian Failure – menopause usually occurs after several decades of menstrual cycles and natural depletion of the ovarian reserve. Premature ovarian failure, or early menopause can be caused by exposure to certain chemicals, chemotherapy and radiation for cancer treatment. It also results from other conditions that affect the cycle-regulating hormones or damage the ovaries so they no longer produce eggs. Certain genetic disorders can trigger premature ovarian failure, as can autoimmune diseases – such as lupus or rheumatoid arthritis – that cause the body to mistakenly attack the ovaries.
- Polycystic Ovarian Syndrome – genetically linked hormonal imbalances can cause polycystic ovarian syndrome (PCOS), a condition that prevents ovulation. Without the necessary level of follicle stimulating hormone (FSH), the follicles don’t develop properly and the eggs don’t mature. An imbalance of luteinizing hormone (LH) causes overproduction of estrogen, abnormal thickening of the uterine lining and very heavy and/or irregular periods. High levels of LH can trigger over production of male hormones, including testosterone, which cause acne and facial hair – common symptoms of PCOS. Over time, elevated estrogen levels associated with PCOS may create an increased risk of uterine cancer and diabetes.
- Hyperprolactinemia – this condition is associated with the pituitary gland located in the brain, which produces prolactin to help regulate ovulation and stimulate breast milk production in pregnant women. Overproduction of prolactin results from tumors on the pituitary, an underactive thyroid (hypothyroidism) or an adverse reaction to certain prescription medications, including antihistamines, oral contraceptives, tranquilizers and antihypertensives. As a result, women experience irregular or no ovulation, and they may produce breast milk even though they aren’t pregnant.
- Hypothalmic Amenorrhea – the hypothalamus gland, also located in the brain, produces gonadotropin-releasing hormone (GnRH). This chemical stimulates the pituitary gland to release follicle stimulating hormone (FSH) and luteinizing hormone (LH). When the hypothalamus stops producing GnRH as a result of this condition, it affects the FSH and LH levels needed for egg development and ovulation.
Treatment Options for Ovulatory Dysfunction
- Medication – birth control pills can stimulate and regulate the menstrual period if a woman is not trying to get pregnant. Infertility patients with PCOS may start with clomiphene citrate, a medication designed to stimulate the ovaries to produce multiple follicles and eggs. Other fertility drugs – human chorionic gonadotropin (HCG) and human menopausal gonadotropin (HMG) – also may be prescribed if clomiphene citrate alone is not effective. Finally, progesterone may be necessary to help thicken the uterine lining and sustain pregnancy.
- Medication also is available to suppress overproduction of prolactin caused by hyperprolactinemia. In cases of hypothalamic amenorrhea, gonadotropins (LH and FSH) are prescribed to regulate levels of these hormones.
- Ovulation Induction (OI) – used alone or with insemination, OI relies on fertility drugs to stimulate development of the follicles and eggs. For this reason, it can be an effective treatment for various forms of ovulatory dysfunction and luteal phase defects. As part of an OI cycle, progesterone may be prescribed alone – or combined with other fertility medications – to stimulate development of the uterine lining to support pregnancy. Human chorionic gonadotropin (HCG) also may be prescribed to overcome luteal phase defects by triggering ovulation.
- In Vitro Fertilization (IVF) – recommended as it may offer the best chance for pregnancy when infertility is related to ovulatory dysfunction. Hormones designed to regulate the reproductive cycle and stimulate the development of multiple eggs will provide more chances for fertilization.
- Donor In Vitro Fertilization – required in cases of premature ovarian failure when there are no eggs available. Eggs from a young female donor, whose body has been stimulated by fertility drugs, are retrieved and fertilized in the laboratory with the male partner’s sperm. The embryos are transferred into the recipient’s uterus, which has been prepared to support pregnancy.