What is infertility?

Infertility is the inability to conceive a child after 12 months (or more) of regular, unprotected sexual intercourse. If a woman is older than age 35, infertility should be evaluated after six months. Infertility may describe both a woman who is having difficulty conceiving as well as a woman who experiences recurrent miscarriages.

Infertility rates have increased over the years. At least 10% of couples in the United States are affected by infertility. This is mostly due to an increase in the age of the couples trying to conceive. Infertility can be caused by problems related to the man or the woman, or infertility can often be “unexplained.”

What are risk factors for infertility?

  • Age: A woman's fertility gradually declines with age and this decline becomes more pronounced in her mid-30s. As a woman gets older, the number and quality of her eggs decrease. Men over age 40 are also less fertile than younger men.
  • Tobacco and alcohol use: The use of tobacco or alcohol by either a woman or a man lessens the chance of achieving a pregnancy. It also has a negative impact on how effective fertility treatments are. Women who smoke have a higher rate of miscarriages and tubal pregnancies. Both alcohol and tobacco use can result in a low sperm count in men.
  • Body weight: The chance of infertility is increased if a person does not lead an active lifestyle, is overweight, or is too thin. In men who are above their ideal weight, sperm counts and testosterone levels may be lower. Women are also at risk of fertility problems if they have an eating disorder like anorexia or bulimia or if they follow a very low calorie or very restrictive diet.
  • Exercise: Not enough exercise contributes to obesity, which increases the risk of infertility. In less common cases, frequent exercise that is strenuous and intense can affect a woman’s ovulation patterns. This can lead to a lack of menstrual cycles (monthly periods).
  • Irregular periods: Irregular menstrual cycles are more common in women who are underweight or overweight. It is important to try to achieve a normal weight via healthy lifestyle changes, and see a gynecologist.
  • History of sexually transmitted infection: Condoms can help preserve future fertility by preventing infections, especially with new partners. Also, talk with your partner about being tested for sexually transmitted infections prior to becoming sexually intimate.

What is required for a couple to become pregnant?

In order for a couple to become pregnant, at least four things have to happen:

  • A woman must produce and release a healthy egg from one of her ovaries (ovulation).
  • A man must produce viable sperm which can successfully fertilize the woman’s egg (fertilization).
  • The egg must travel through a fallopian tube toward the uterus (transportation).
  • The fertilized egg must attach to the inside of the uterus (implantation).

What can I do to improve fertility?

  • Maintain a healthy weight and avoid extreme diets.
  • Eat a healthy, well-balanced diet.
  • Avoid illegal drugs and tobacco.
  • Consume alcohol in moderation or avoid it entirely.
  • Get regular exercise at moderate level of intensity.
  • Avoid exposure to industrial or environmental toxins.
  • Avoid medicines that may affect fertility; check with your health care provider.
  • Limit how much caffeine you consume.

What are the causes of low sperm count or abnormal sperm function in men?

Low sperm count or abnormal sperm function may be caused by different things. These include:

  • Undescended testicles
  • Genetic defects/DNA damage
  • Diabetes
  • Prior bacterial or viral infections such as mumps or adenovirus
  • Trauma or prior surgeries on the testicles or inguinal region
  • Enlarged veins (varicoceles) in the testes that can increase blood flow and heat, both of which affect the number and shape of the sperm
  • Exposure to chemicals like pesticides, radiation, and chemotherapy
  • Alcohol use, marijuana use, and tobacco smoke
  • Steroid use
  • Overexposure to heat (such as in saunas and hot tubs)
  • Surgical removal of one of the testicles due to cancer

In addition, there can be problems with the delivery of sperm and subsequent fertilization due to any of the following:

  • Premature ejaculation
  • Damage or injury to the reproductive organs
  • Semen entering the bladder instead of emerging through the penis during orgasm (retrograde ejaculation)
  • Certain genetic diseases (such as cystic fibrosis)

Men who have previously had a vasectomy and wish to father a child have two choices. They either need to have the vasectomy reversed or have sperm retrieved through a surgical procedure as part of assisted reproductive techniques.

What are the causes of infertility in women?

The causes of infertility in women can include many of the following:

  • Hormonal issues: When hormone disorders are present, problems with ovulation can occur. These can be due to the lack of the necessary synchronized hormonal changes leading to the release of an egg from the ovary.
    • Disorders of the thyroid gland: Either too much thyroid hormone or too little thyroid hormone can interfere with the menstrual cycle or cause infertility
    • Gland disorders: These hormonal disorders may include polycystic ovarian syndrome (PCOS), or problems with the hypothalamus, pituitary gland, adrenal gland (such as Cushing's syndrome or congenital adrenal hyperplasia)
  • Structural issues: Benign growths (such as polyps and fibroids) in the uterus, blocked fallopian tubes, abnormal anatomy of the cervix or uterus, endometriosis, scar tissue
    • Fallopian tube damage can include scarring from prior surgery and/or pelvic infections. These include pelvic inflammatory disease (PID) due to chlamydia or gonorrhea. Problems with transportation of the egg(s) can occur due to damaged or blocked fallopian tubes.
  • Diminished ovarian reserve, premature menopause or cessation of ovulation (primary ovarian insufficiency); changes in egg quality or quantity can affect fertility
  • Additional factors:
    • Poor diet that is lacking in nutrients
    • Athletic overtraining
    • Stress
    • Too much exposure to certain chemicals and toxins (for example, tobacco smoke, alcohol, marijuana, pesticides, radiation, and chemotherapy)
    • Certain medications (the effect usually is temporary)
    • Sickle cell disease
    • Kidney disease
    • Celiac disease
    • Diabetes

Women who have had a tubal ligation or an Essure® device (forms of permanent birth control) should speak with a gynecologist about their options.

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