Infertility is defined by the American Society for Reproductive Medicine (ASRM) as a disease of the reproductive system that impairs the body's ability to perform the basic function of reproduction. Although conceiving a child may seem to be simple and natural, the physiological process is quite complicated and depends on the proper function of many factors, including the following, as listed by the ASRM:
- production of healthy sperm by the man
- production of healthy eggs by the woman
- unblocked fallopian tubes that allow the sperm to reach the egg
- the sperm's ability to fertilize the egg
- the ability of the fertilized egg to become implanted in the uterus
- adequate embryo quality
Infertility affects about 12 percent of couples of childbearing age. Infertility is not just a woman's concern. A problem with the male is the sole cause, or a contributing cause, of infertility in about 50 percent of infertile couples. About one-third of infertile couples have more than one cause or factor related to their inability to conceive. About 20 percent of couples have no identifiable cause for their infertility after medical investigation.
Many different factors and problems can cause infertility, including problems in the female reproductive system, the male reproductive system, or a combination of the two. The following are some of the conditions or factors that are associated with infertility:
- female factors
- ovulation dysfunction
With this condition, the woman's reproductive system does not produce the proper amounts of hormones necessary to develop, mature, and release a healthy egg.
- anatomical problems
Abnormal development or function of the female anatomy can prevent the egg and the sperm from meeting. The most common anatomical problem is blockage of the fallopian tubes. Other anatomical problems may include the presence of pelvic scar tissue from previous surgeries or infections.
Endometriosis is a condition in which the tissue that lines the uterus develops outside the uterus, usually on other reproductive organs inside the pelvis or in the abdominal cavity. Each month, this misplaced tissue responds to the hormonal changes of the menstrual cycle by building up and breaking down, resulting in internal bleeding which can cause scar tissue to form and affect reproductive organ function.
- birth defects
Abnormal development and function of reproductive organs resulting from birth defects can affect fertility. One of the most common reproductive system birth defects occurs following a woman's exposure to DES (diethylstilbestrol) taken by her mother during pregnancy. In years past, DES was given to women at risk for pregnancy loss. Fetal DES exposure often causes abnormal development of the uterus and cervix.
Pelvic inflammatory disease (PID) is caused by a type of bacteria such as gonorrhea and chlamydia. PID can affect the uterus, fallopian tubes, and/or the ovaries. It can lead to pelvic adhesions and scar tissue that develops between internal organs, causing ongoing pelvic pain and the possibility of an ectopic pregnancy (the fertilized egg becomes implanted outside the uterus).
- immunological problems
A problem with a woman's immune system can lead to pregnancy loss. Antibodies (immune or protective proteins) in a woman's system can fail to recognize a pregnancy, or there may be an abnormal immune response to the pregnancy. Women can also develop antisperm antibodies which attack and destroy sperm.
- male factors
- low or absent sperm production
Without proper numbers of healthy sperm, the chance of fertilization is decreased.
- abnormal sperm function
Sperm must have proper motility and the ability to penetrate the egg.
This is a condition in which varicose veins develop around the testes. It is a very common cause of male factor infertility and is usually treatable and reversible with surgery.
Use of recreational drugs (i.e., marijuana, cocaine), heavy alcohol use, cigarette smoking, certain medications, and excessive heat to the genital area (as in hot tubs) can affect sperm quality and function.
- hormonal disorders
Improper male hormone or endocrine function can affect sperm production and fertilization ability.
- chromosomal defects
Certain chromosomal abnormalities are associated with male infertility.
- birth defects
Abnormalities in a man's reproductive system can occur during fetal development. Some birth defects are due to a man's exposure to DES (diethylstilbestrol) taken by his mother during pregnancy.
- immunological problems
A man may have antisperm antibodies (immune or protective proteins) which attack and destroy sperm
When conception does not occur after one year of unprotected intercourse, after six months in women over age 35, or if there are known problems causing infertility, a medical evaluation of both the male and female is recommended. Some obstetrician/gynecologists (OB/GYNs) are able to provide basic infertility evaluation and treatment. However, many causes of infertility are best treated by a board-certified reproductive endocrinologist. This is an OB/GYN who has had additional education and training in infertility and is certified with the American Board of Obstetrics and Gynecology in the sub-specialty of Reproductive Endocrinology and Infertility.
Generally, the OB/GYN or reproductive endocrinologist will evaluate specific situations and perform tests in both the male and female partners to determine the cause of infertility. The physician is looking for answers to the following questions:
- Is the female ovulating regularly?
- Is the male producing healthy, viable sperm?
- Are the female's egg and the male's sperm able to unite and grow normally?
- Are there any obstacles to proper implantation and maintenance of the pregnancy?
The following tests are often part of the basic medical workup for infertility.
- both partners
- medical and sexual history (to evaluate possible physical causes of infertility and if sexual intercourse has been appropriately timed)
- physical examination
A complete physical examination (including a Pap smear and testing for infection) will be necessary.
- ovulation evaluation
An evaluation of ovulation function using an analysis of body temperatures and ovulation called the basal body temperature chart, or with ovulation prediction methods using urine samples, may be recommended.
- hormone testing
Hormone testing may be recommended, as certain hormones increase and decrease in production at various times in the monthly cycle.
Ultrasound can show the presence of follicles (the sacs containing developing eggs) and the thickness of the uterine tissues. Ultrasound can also show abnormal conditions, such as ovarian cysts or fibroids (benign tumors in the uterus).
A hysterosalpingogram may be recommended. This test uses a radio-opaque dye injected into the cervical opening to visualize the inside of the uterus and determine if the fallopian tubes are open.
Men may be referred to a urologist for further evaluation.
- semen analysis
A collection of a semen sample obtained by masturbation that is analyzed in the laboratory for the sperm count, sperm motility, sperm shape, quantity, and evaluation of the ejaculate liquid may be recommended. According to the ASRM, a normal ejaculate contains more than 20 million sperm per milliliter of liquid, more than 50 percent of the sperm should be moving forward, and more than 30 percent of sperm should have normal shapes.
- other tests may be performed that evaluate the sperm's ability to penetrate the egg, as well as male hormone testing
Specific treatment for infertility will be determined by your physician based on:
- your age, overall health, and medical history
- extent of the disorder
- cause of the disorder
- your tolerance for specific medications, procedures, or therapies
- expectations for the course of the disorder
- your opinion or preference
Once a diagnosis is made, the specialist can work with you to determine the course of treatment. According to the ASRM, most infertility cases (85 to 90 percent) are treated with conventional therapies, such as drug treatment or surgical repair of reproductive abnormalities. Depending on the cause of infertility, there are many options to offer an infertile couple.
Types of treatments for women may include the following:
A: In 2005, of ART cycles that used fresh, non-donor eggs or embryos, 66 percent of these cycles did not produce a pregnancy in women less than 35 years old.
Clinical pregnancy was achieved in 34 percent of these ART cycles.
21.4 percent resulted in a single-fetus pregnancy.
11.2 percent resulted in a multiple-fetus pregnancy.
Source: National Center for Chronic Disease Prevention and Health Promotion
- ovulation medications
These medications help regulate the timing of ovulation and stimulate the development and release of mature eggs. They can also help correct hormonal problems that can affect the lining of the uterus as it prepares to receive a fertilized egg. Ovulation medications can stimulate more than one egg to be released which increases the possibility of having twins and other multiples. Some of the common ovulation medications include the following:
- clomiphene citrate
- human menopausal gonadotropins - medications containing follicle-stimulating hormone (FSH) and luteinizing hormone (LH)
- follicle-stimulating hormone (FSH)
- intrauterine insemination
For some conditions, including low sperm count and cervical mucus problems, a procedure that places specially washed and prepared sperm directly into the uterus through a small catheter (flexible tube) helps increase the chances for conception. This procedure is often used in combination with ovulation medications.
Surgery may be used to treat or repair a condition that is causing infertility such as fallopian tube blockage, or endometriosis. A common surgical procedure often used as part of the diagnostic workup of infertility is the laparoscopy. In a laparoscopy, a small telescope inserted into the abdominal or pelvic cavity allows internal organs to be visualized. Some procedures to treat infertility can be performed using instruments inserted through the laparoscope.
- assisted reproductive technology (ART)
For some couples, more extensive treatment is needed. With most forms of ART, the sperm and egg are united in the laboratory and the fertilized egg is returned to the woman's uterus where it can implant and develop. Although ART procedures are often costly, many are being used with success. These include the following:
- in vitro fertilization (IVF) - involves extracting a woman's eggs, fertilizing the eggs in the laboratory with sperm, and then transferring the resulting embryo(s) into the woman's uterus through the cervix (embryo transfer) where it can develop. Most couples transfer two embryos; however, more may be transferred in certain cases. IVF is the most common form of ART and it is often the treatment of choice for a woman with blocked, severely damaged, or absent fallopian tubes. IVF is also used for infertility caused by endometriosis or male factor infertility. IVF is sometimes used to treat couples with long-term unexplained infertility who have not been able to conceive with other infertility treatments. According to the ASRM, the average cost of one IVF cycle in the United States is $12,400. More than one IVF cycle, however, is usually needed.
- intracytoplasmic sperm injection (ICSI) - a procedure in which a single sperm is injected directly into an egg; this procedure is most commonly used to help with male factor infertility problems.
- gamete intrafallopian transfer (GIFT) - involves using a fiber-optic instrument called a laparoscope to guide the transfer of unfertilized eggs and sperm into the woman's fallopian tubes through small incisions in her abdomen. GIFT is only used in women with healthy fallopian tubes.
- zygote intrafallopian transfer (ZIFT) - involves fertilizing a woman's eggs in the laboratory and then using a laparoscope to guide the transfer of the fertilized eggs (zygotes) into her fallopian tubes. ZIFT is only used in women with healthy fallopian tubes.
- donor eggs - involves an embryo formed from the egg of one woman (the donor) being transferred to another woman who is unable to conceive with her own eggs (the recipient). The donor relinquishes all parental rights to any resulting offspring. ART using donor eggs is much more common among older women than among younger women. The likelihood of a fertilized egg implanting is related to the age of the woman who produced the egg. Egg donors are typically in their 20s or early 30s.
- embryo cryopreservation - a procedure in which embryos are preserved through freezing (cryopreservation) for transfer at a later date. This procedure is often used when an IVF cycle produces more embryos than can be transferred at one time. The remaining embryos can be transferred in a future cycle if the woman does not become pregnant.
There is a range of treatment options currently available for male factor infertility. Treatment may include:
- assisted reproductive technologies (ART)
This type of treatment may include the following:
- artificial insemination
Artificial insemination involves the placement of relatively large numbers of healthy sperm either at the entrance of the cervix or into the partner's uterus, bypassing the cervix, to have direct access to the fallopian tubes.
- IVF, GIFT, and other techniques
In vitro fertilization (IVF) or gamete intra-fallopian transfer (GIFT) have been used for the treatment of male infertility. As is the case with artificial insemination, IVF and similar techniques offer the opportunity to prepare sperm in vitro, so that oocytes are exposed to an optimal concentration of high quality, motile sperm.
- microsurgical fertilization (microinjection techniques such as intracytoplasmic sperm injection, or ICSI)
This treatment is used to facilitate sperm penetration by injection of a single sperm into the oocyte. Fertilization then takes place under the microscope.
- drug therapy
A small percentage of infertile men have a hormonal disorder that can be treated with hormone therapy. Hormonal imbalances caused by a dysfunction in the mechanism of interaction between the hypothalamus, the pituitary gland, and the testes directly affect the development of sperm (spermatogenesis). Drug therapy may include gonadotrophin therapy, antibiotics, or another medication deemed appropriate.
Surgical therapy in male infertility is designed to overcome anatomical barriers that impede sperm production and maturation or ejaculation. Surgical procedures to remove varicose veins in the scrotum (varicocele) can sometimes serve to improve the quality of sperm.
About 20 percent of couples have unexplained infertility, for which a cause, despite all investigations, is not found. Unexplained infertility does not mean there is no reason for the problem, but that the reason is unable to be identified at the present time.
If you suspect you are experiencing infertility, seek medical consultation early. The age of the woman and the duration of the couple's infertility may influence the success of treatment.