Infertility refers to an inability to conceive after having regular unprotected sex. Infertility can also refer to the biological inability of an individual to contribute to conception, or to a female who cannot carry a pregnancy to full term. In many countries, infertility refers to a couple that has failed to conceive after 12 months of regular sexual intercourse without the use of contraception.
Studies indicate that slightly over half of all cases of infertility are a result of female conditions, while the rest are caused by either sperm disorders or unidentified factors.
Causes of female infertility
- Causes of female infertility may include: Ovulation disorders, which affect the release of eggs from the ovaries. These include hormonal disorders such as polycystic ovary syndrome. Hyperprolactinemia, a condition in which you have too much prolactin — the hormone that stimulates breast milk production — may also interfere with ovulation. Either too much thyroid hormone (hyperthyroidism) or too little (hypothyroidism) can affect the menstrual cycle or cause infertility. Other underlying causes may include excessive exercise, eating disorders, injury or tumors.
- Uterine or cervical abnormalities, including abnormalities with the opening of the cervix, polyps in the uterus or the shape of the uterus. Noncancerous (benign) tumors in the uterine wall (uterine fibroids) may rarely cause infertility by blocking the fallopian tubes. More often, fibroids interfere with implantation of the fertilized egg.
- Fallopian tube damage or blockage, often caused by inflammation of the fallopian tube (salpingitis). This can result from pelvic inflammatory disease, which is usually caused by a sexually transmitted infection, endometriosis or adhesions.
- Endometriosis, which occurs when endometrial tissue grows outside of the uterus, may affect the function of the ovaries, uterus and fallopian tubes.
- Primary ovarian insufficiency (early menopause), when the ovaries stop working and menstruation ends before age 40. Although the cause is often unknown, certain factors are associated with early menopause, including immune system diseases, certain genetic conditions such as Turner syndrome or carriers of Fragile X syndrome, radiation or chemotherapy treatment, and smoking.
- Pelvic adhesions, bands of scar tissue that bind organs after pelvic infection, appendicitis, or abdominal or pelvic surgery.
Other causes in women include:
- Cancer and its treatment: Certain cancers — particularly female reproductive cancers — often severely impair female fertility. Both radiation and chemotherapy may affect fertility.
- Other conditions: Medical conditions associated with delayed puberty or the absence of menstruation (amenorrhea), such as celiac disease, poorly controlled diabetes and some autoimmune diseases such as lupus, can affect a woman’s fertility. Genetic abnormalities also can make conception and pregnancy less likely.
Causes of male infertility
- Abnormal sperm production or function due to undescended testicles, genetic defects, health problems such as diabetes or infections such as chlamydia, gonorrhea, mumps or HIV. Enlarged veins in the testes (varicocele) can also affect the quality of sperm.
- Problems with the delivery of sperm due to sexual problems, such as anejaculation , erectile dysfunction; certain genetic diseases, such as cystic fibrosis; structural problems, such as a blockage in the testicle; or damage or injury to the reproductive organs.
- Overexposure to certain environmental factors, such as pesticides and other chemicals, and radiation. Cigarette smoking, alcohol, marijuana or taking certain medications, such as certain antibiotics, antihypertensives, anabolic steroids or others, can also affect fertility. Frequent exposure to heat, such as in saunas or hot tubs, can raise the core body temperature and may affect sperm production.
- Damage related to cancer and its treatment, including radiation or chemotherapy. Treatment for cancer can impair sperm production, sometimes severely.
When to see a doctor
You probably don’t need to see a doctor about infertility, unless you have tried regularly to conceive for at least one year. Talk with your doctor earlier, however, if you’re a woman and:
- You’re age 35 to 40 and have been trying to conceive for six months or longer
- You’re over age 40
- You menstruate irregularly or not at all
- Your periods are very painful
- You have known fertility problems
- You’ve been diagnosed with endometriosis or pelvic inflammatory disease
- You’ve had multiple miscarriages
- You’ve undergone treatment for cancer
Talk with your doctor if you’re a man and:
- You have a low sperm count or other problems with sperm
- You have a history of testicular, prostate or sexual problems
- You’ve undergone treatment for cancer
- You have testicles that are small in size or swelling in the scrotum known as a varicocele
- You have others in your family with infertility problems