In general, infertility is defined as not being able to get pregnant (conceive) after one year (or longer) of unprotected sex. Because fertility in women is known to decline steadily with age, some providers evaluate and treat women aged 35 years or older after 6 months of unprotected sex. While these definitions of infertility are used for data collection and monitoring, they are not intended to guide recommendations about the provision of fertility care services. Individuals and couples who are unable to conceive a child should consider making an appointment with a reproductive endocrinologist—a doctor who specializes in managing infertility. Reproductive endocrinologists may also be able to help women with recurrent pregnancy loss, defined as having two or more spontaneous miscarriages.
Pregnancy is the result of a process that has many steps. To get pregnant:
- A woman’s body must release an egg from one of her ovaries.
- A man’s sperm must join with the egg along the way (fertilize).
- The fertilized egg must go through a fallopian toward the uterus (womb).
- The embryo must attach to the inside of the uterus (implantation).
Infertility may result from a problem with any or several of these steps.
Impaired fecundity is a condition related to infertility and refers to women who have difficulty getting pregnant or carrying a pregnancy to term.
Yes. In the United States, among married women aged 15 to 49 years with no prior births, about 1 in 5 (19%) are unable to get pregnant after one year of trying (infertility). Also, about 1 in 4 (26%) women in this group have difficulty getting pregnant or carrying a pregnancy to term (impaired fecundity).
Infertility and impaired fecundity are less common among women with one or more prior births. In this group, about 6% of married women aged 15 to 49 years are unable to get pregnant after one year of trying and 14% have difficulty getting pregnant or carrying a pregnancy to term.
Infertility in men can be caused by different factors and is typically evaluated by a semen analysis. When a semen analysis is performed, the number of sperm (concentration), motility (movement), and morphology (shape) are assessed by a specialist. A slightly abnormal semen analysis does not mean that a man is necessarily infertile. Instead, a semen analysis helps determine if and how male factors are contributing to infertility.
Disruption of testicular or ejaculatory function
- Varicocele, a condition in which the veins within a man’s testicle are enlarged. Although there are often no symptoms, varicoceles may affect the number or shape of the sperm.
- Trauma to the testes may affect sperm production and result in lower number of sperm.
- Heavy alcohol use, smoking, anabolic steroid use, and illicit drug use.
- Cancer treatment involving certain types of chemotherapy, radiation, or surgery to remove one or both testicles.
- Medical conditions such as diabetes, cystic fibrosis, certain types of autoimmune disorders, and certain types of infections may cause testicular failure.
- Improper function of the hypothalamus or pituitary glands. The hypothalamus and pituitary glands in the brain produce hormones that maintain normal testicular function. Production of too much prolactin, a hormone made by the pituitary gland (often due to the presence of a benign pituitary gland tumor), or other conditions that damage or impair the function of the hypothalamus or the pituitary gland may result in low or no sperm production.
- These conditions may include benign and malignant (cancerous) pituitary tumors, congenital adrenal hyperplasia, exposure to too much estrogen, exposure to too much testosterone, Cushing’s syndrome, and chronic use of medications called glucocorticoids.
- Genetic conditions such as a Klinefelter’s syndrome, Y-chromosome microdeletion, myotonic dystrophy, and other, less common genetic disorders may cause no sperm or low numbers of sperm to be produced.
- Age. Although advanced age plays a much more important role in predicting female infertility, couples in which the male partner is 40 years old or older are more likely to report difficulty conceiving.
- Being overweight or obese.
- Excessive alcohol and drug use (opioids, marijuana).
- Exposure to testosterone. This may occur when a doctor prescribes testosterone injections, implants, or topical gel for low testosterone, or when a man takes testosterone or similar medications illicitly for the purposes of increasing their muscle mass.
- Exposure to radiation.
- Frequent exposure of the testes to high temperatures, such as that which may occur in men confined to a wheelchair, or through frequent sauna or hot tub use.
- Exposure to certain medications such as flutamide, cyproterone, bicalutamide, spironolactone, ketoconazole, or cimetidine.
- Exposure to environmental toxins including exposure to pesticides, lead, cadmium, or mercury.
Women need functioning ovaries, fallopian, and a uterus to get pregnant. Conditions affecting any one of these organs can contribute to female infertility. Some of these conditions are listed below and can be evaluated using several different tests.
Disruption of ovarian function (presence or absence of ovulation and effects of ovarian “age”)
A woman’s menstrual cycle is, on average, 28 days long. Day 1 is defined as the first day of “full flow.” Regular predictable periods that occur every 21 to 35 days likely reflect ovulation. A woman with irregular periods is likely not ovulating.
Ovulation can be predicted by using an ovulation predictor kit and can be confirmed by a blood test to check the woman’s progesterone level on day 21 of her menstrual cycle. Although several tests exist to evaluate a woman’s ovarian function, no single test is a perfect predictor of fertility. The most commonly used markers of ovarian function include follicle-stimulating hormone (FSH) value on day 3 to 5 of the menstrual cycle, anti-müllerian hormone value (AMH), and antral follicle count (AFC) using a transvaginal ultrasound.
Disruption in ovarian function may be caused by several conditions and warrants an evaluation by a doctor.
When a woman doesn’t ovulate during a menstrual cycle, it’s called anovulation. Potential causes of anovulation include the following
- Polycystic ovary syndrome (PCOS). PCOS is a condition that causes women to not ovulate, or to ovulate irregularly. Some women with PCOS have elevated levels of testosterone, which can cause acne and excess hair growth. PCOS is the most common cause of female infertility.
- Diminished ovarian reserve (DOR). Women are born with all of the eggs that they will ever have, and the number of eggs declines naturally over time. DOR is a condition in which there are fewer eggs remaining in the ovaries than expected for a given age. It may occur due to congenital (condition present at birth), medical, surgical, or unexplained causes. Women with DOR may be able to conceive naturally, but will produce fewer eggs in response to fertility treatments.
- Functional hypothalamic amenorrhea (FHA). FHA is a condition caused by excessive exercise, weight loss, stress, or often a combination of these factors. It is sometimes associated with eating disorders such as anorexia.
- Improper function of the hypothalamus and pituitary glands. The hypothalamus and pituitary glands in the brain produce hormones that maintain normal ovarian function. Production of too much of the hormone prolactin by the pituitary gland (often as the result of a benign pituitary gland tumor), or improper function of the hypothalamus or pituitary gland, may cause a woman not to ovulate.
- Premature ovarian insufficiency (POI). POI, sometimes referred to as premature menopause, occurs when a woman’s ovaries fail before she is 40 years of age. Although certain exposures, such as chemotherapy or pelvic radiation therapy, and certain medical conditions may cause POI, the cause is often unexplained. About 5% to 10% of women with POI conceive naturally and have a normal pregnancy.
- Menopause. Menopause is a natural decline in ovarian function that usually occurs around age 50. By definition, a woman in menopause has not had a period for at least one year. Many women experience hot flashes, mood changes, difficulty sleeping, and other symptoms as well.
Fallopian tube obstruction (whether fallopian tubes are open, blocked, or swollen)
Fallopian tubes may be evaluated by hysterosalpingogram or by chromopertubation.
- Hysterosalpingogram is an X-ray of the uterus and fallopian tubes. A radiologist injects dye into the uterus through the cervix and simultaneously takes X-ray pictures to see if the dye moves freely through fallopian tubes indicating they are open.
- Chromopertubation is similar to a hysterosalpingogram but is done in the operating room at the time of a laparoscopy. Blue-colored dye is passed through the cervix into the uterus and through the fallopian tubes. This test is used to evaluate if the fallopian tubes are open and to assess if they are dilated.
Physical characteristics of the uterus
Depending on a woman’s symptoms, the uterus may be evaluated by transvaginal ultrasound to look for fibroids or other problems, including intrauterine adhesions, endometrial polyps, adenomyosis, and congenital anomalies of the uterus. A sonohystogram or hysteroscopy may also be performed to further evaluate the uterine environment.
Female fertility is known to decline with
- Age. About 1 in 5 (22%) married couples in which the woman is 30-39 have problems conceiving their first child compared to about 1 in 8 (13%) married couples in which the woman is younger than 30. Fertility declines with age primarily because egg quality declines over time. In addition, older women have fewer eggs left and they are more likely to have health conditions that can cause fertility problems. Aging also increases a woman’s chances of miscarriage and of having a child with a genetic abnormality.
- Excessive alcohol use.
- People with overweight or obesity or underweight.
- Extreme weight gain or loss.
- Excessive physical or emotional stress that results in amenorrhea (absent periods).
A woman’s chances of having a baby decrease rapidly every year after the age of 30. Most experts suggest women younger than age 35 with no apparent health or fertility problems and regular menstrual cycles should try to conceive for at least one year before seeing a doctor. However, for women aged 35 years or older, couples should see a health care provider after 6 months of trying unsuccessfully. Women over 40 years may consider seeking more immediate evaluation and treatment.
Some health problems also increase the risk of infertility. So, couples with the following signs or symptoms should not delay seeing their health care provider when they are trying to become pregnant:
- Irregular periods or no menstrual periods
- A history of pelvic inflammatory disease
- Known or suspected uterine or tubal disease
- A history of more than one miscarriage
- Genetic or acquired conditions that predispose to diminished ovarian reserve (chemotherapy, radiation)
- A history of testicular trauma
- Prior hernia surgery
- Prior use of chemotherapy
- A history of infertility with another partner
- Sexual dysfunction
It is a good idea for any woman and her partner to talk to a health care provider before trying to get pregnant. They can help you get your body ready for a healthy baby, and can also answer questions on fertility and give tips on conceiving. Learn more at the CDC’s Preconception Health web site.
Often, medication and intrauterine insemination are used at the same time. Doctors recommend specific treatments for infertility on the basis of:
- The factors contributing to the infertility.
- The duration of the infertility.
- The age of the female.
- The couple’s treatment preference after counseling about success rates, risks, and benefits of each treatment option.
Male infertility may be treated with medical, surgical, or assisted reproductive therapies depending on the underlying cause. Medical and surgical therapies are usually managed by a urologist who specializes in infertility. A reproductive endocrinologist may offer intrauterine inseminations (IUIs) or in vitro fertilization (IVF) to help overcome male factor infertility.
- Clomiphene citrate (Clomid®*) is a medicine that causes ovulation by acting on the pituitary gland. It is often used in women who have polycystic ovary syndrome (PCOS) or other problems with ovulation. It is also used in women with normal ovulation to increase the number of mature eggs produced. This medicine is taken by mouth.
- Letrozole (Femara®*) is a medication that is frequently used off-label to cause ovulation. It works by temporarily lowering a woman’s progesterone level, which causes the brain to naturally make more follicle-stimulating hormone (FSH). It is often used to induce ovulation in woman with PCOS, and in women with normal ovulation to increase the number of mature eggs produced in the ovaries. It is taken by mouth.
- Human menopausal gonadotropin or hMG (Menopur®*; Repronex®*; Pergonal®*) is an injectable medication often used for women who don’t ovulate because of problems with their pituitary gland—hMG acts directly on the ovaries to stimulate development of mature eggs.
- Follicle-stimulating hormone or FSH (Gonal-F®*; Follistim®*) is an injectable medication that works much like hMG. It stimulates development of mature eggs within the ovaries.
- Gonadotropin-releasing hormone (GnRH) analogs and GnRH antagonists are medications that act on the pituitary gland to prevent a woman from ovulating. They are used during in vitro fertilization cycles, or to help prepare a woman’s uterus for an embryo transfer. These medications are usually injected or given with a nasal spray.
- Metformin (Glucophage®*) is a medicine doctors use for women who have insulin resistance or diabetes and PCOS. This drug helps lower the high levels of male hormones in women with these conditions. This helps the body to ovulate. Sometimes clomiphene citrate or FSH is combined with metformin. This medicine is taken by mouth.
- Bromocriptine (Parlodel®*) and Cabergoline (Dostinex®*) are medications used for women with ovulation problems because of high levels of prolactin. These medications are taken by mouth.
*Note: Use of trade names and commercial sources is for identification only and does not imply endorsement by the US. Department of Health and Human Services.
Many fertility drugs increase a woman’s chance of having twins, triplets, or other multiples. Women who are pregnant with multiple fetuses may have more problems during pregnancy. Multiple fetuses have a higher risk of being born prematurely (too early). Premature babies are at a higher risk of health and developmental problems.
Intrauterine insemination (IUI) is an infertility treatment that is often called artificial insemination. In this procedure, specially prepared sperm are inserted into the woman’s uterus. Sometimes the woman is also treated with medicines that stimulate ovulation before IUI.
IUI is often used to treat:
- Mild male factor infertility.
- Couples with unexplained infertility.
Assisted Reproductive Technology (ART) includes all fertility treatments in which either eggs or embryos are handled outside of the body. In general, ART procedures involve removing mature eggs from a woman’s ovaries using a needle, combining the eggs with sperm in the laboratory, and returning the embryos to the woman’s body or donating them to another woman. The main type of ART is in vitro fertilization (IVF).
Success rates vary and depend on many factors, including the clinic performing the procedure, the infertility diagnosis, and the age of the woman undergoing the procedure. This last factor—the woman’s age—is especially important.
CDC publishes ART success rates for all fertility clinics in the United States. In addition, CDC created an IVF Success Estimator – a tool to estimate the chance of having a live birth using IVF based on the experiences of women and couples with similar characteristics.
ART can be expensive and time-consuming, but it has allowed many couples to have children that otherwise would not have been conceived. The most common complication of ART is a multiple pregnancy. This is a problem that can be prevented or minimized by limiting the number of embryos that are transferred back to the uterus. For example, transfer of a single embryo, rather than multiple embryos, greatly reduces the chances of a multiple pregnancy and its risks such as preterm birth.
- In vitro fertilization (IVF), meaning fertilization outside of the body, is the most common form of ART. Eggs and sperm are combined in a laboratory to create embryos. After about three to five days, the embryo (or embryos) is transferred into the woman’s uterus. Embryos can also be frozen for a future transfer. When a frozen embryo is thawed and transferred into a woman’s uterus it is called a frozen embryo transfer (FET).
- Intracytoplasmic sperm injection (ICSI) is a type of IVF that is often used for couples with male factor infertility. With ICSI, a single sperm is injected into a mature egg. The alternative to ICSI is “conventional” fertilization where the egg and many sperm are placed in a petri dish together and the sperm fertilizes an egg on its own.
- Zygote intrafallopian transfer (ZIFT) or tubal embryo transfer and gamete intrafallopian transfer (GIFT) are other ART methods that are rarely used in the United States today. With ZIFT, fertilization occurs in the laboratory similar to IVF. Then the very young embryo is transferred to the fallopian tube instead of the uterus. GIFT involves transferring eggs and sperm into the woman’s fallopian tube and fertilization occurs in the woman’s body.
ART procedures sometimes involve the use of donor eggs (eggs from another woman), donor sperm, or donated embryos. Donor eggs are sometimes used for women who cannot produce eggs. Also, donor eggs or donor sperm are sometimes used when the woman or man has a genetic disease that can be passed on to the baby. An infertile couple may also use donated embryos that were created by other couples in infertility treatment and were not used. When donated embryos are used the child will not be genetically related to either parent. Donor eggs, sperm, or donated embryos may also be used by same-sex couples.
Women with ovaries but no uterus may be able to use a gestational carrier. This may also be an option for women who shouldn’t become pregnant because of a serious health problem. In this case, a woman uses her own egg and it is fertilized by her partner’s sperm. Then, the embryo is placed inside the carrier’s uterus.
Preimplantation genetic testing is a procedure used to identify genetic disorders or chromosomal abnormalities in embryos created during an IVF cycle. One or more cells are biopsied from each embryo and sent for testing. These procedures used to be referred to as preimplantation genetic screening and preimplantation genetic diagnosis.
- Trying to Get Pregnant? – (March of Dimes)
- Infertility – (MedlinePlus)
- RESOLVE: The National Infertility Association – RESOLVE is a national consumer organization that offers support for men and women dealing with infertility. Their purpose is to provide timely, compassionate support and information to people who are experiencing infertility and to increase awareness of infertility issues through public education and advocacy.
- Path 2 Parenthood – Path2Parenthood (P2P) is nonprofit organization that helps people create their families by providing outreach programs and educational information.
- PCOS Challenge – PCOS Challenge is a support organization for women with polycystic ovary syndrome.
- American Society for Reproductive Medicine -The American Society for Reproductive Medicine (ASRM) is a multidisciplinary organization that provides information, education, advocacy, and standards in reproductive medicine.
- Society for Assisted Reproductive Technology – The Society for Assisted Reproductive Technology (SART) promotes and advances the standards for the practice of assisted reproductive technology to the benefit of patients, members, and society at large.
- Society for Women’s Health Research – The Society for Women’s Health Research is dedicated to promoting research on biological sex differences in disease and improving women’s health through science, policy, and education.
- American Urological Association – The American Urological Association promotes the highest standards of urological clinical care through education, research and the formulation of health care policy.
- Urology Care Foundation – The official foundation of the American Urological Association provides educational services and referrals to benefit patients with male infertility, and is committed to advancing urologic research and education to improve patient’s lives.
- CDC’s National Assisted Reproductive Technology Surveillance System – CDC’s Division of Reproductive Health collects and publishes information on assisted reproductive technology (ART) procedures performed in US fertility clinics. The reports include individual clinic tables that provide ART success rates and other information from each clinic.
- Human Cell, Tissues, and Cellular and Tissue-Based Products – A list of ART clinics registered with FDA.
- World Health Organization (WHO) – World Health Organization works worldwide to promote health, keep the world safe, and serve the vulnerable. WHO is committed to addressing infertility and fertility care.