Infertility is the inability to become pregnant after 12 months of unprotected sex (intercourse).

Primary infertility is the term used to describe a couple that has never been able to achieve a pregnancy after at least 1 year of unprotected sex.

Secondary infertility describes couples who have been pregnant at least once, but have not been able to achieve a pregnancy again.

Causes of infertility include a wide range of physical and emotional factors. About 30 - 40% of all infertility is due to a "male" factor such as:

• Decreased sperm count
• Environmental pollutants
• Hormone deficiency
• Impotence
• Retrograde ejaculation
• Scarring from sexually transmitted disease

Some factors that affect sperm count are:

• Heavy marijuana use
• Use of prescription drugs such as cimetidine, spironolactone, and nitrofurantoin

"Female" factor causes include:

• Abnormal egg transport from the cervix through the fallopian tubes (causes 40 - 50% of infertility in couples)
• Hormone imbalance
• Ovarian cysts
• Pelvic infection
• Poor nutrition
• Problem with ovulation
• Scarring from sexually transmitted disease or endometriosis
• Tumor

The other 10 -30% of infertility cases may be caused by factors from both partners, or no cause that can be identified.

About 10 - 20% of couples will be unable to conceive after 1 year of trying to become pregnant. It is important that you try to get pregnant for at least 1 year.

The chances for a pregnancy in healthy couples who are both under the age of 30 and having sex regularly is only 25 - 30% per month. A woman's peak fertility occurs in her early 20s. As a woman ages beyond 35 (and especially after age 40), the likelihood of getting pregnant drops to less than 10% per month.

In addition to age-related factors, other infertility risks include:

• Anovulatory menstrual cycles
• Autoimmune disorders, such as antiphospholipid syndrome (APS)
• Clotting disorders (thrombophilia)
• Defects of the uterus (myomas) or blockage of the cervix
• Eating disorders (women)
• Endometriosis
• Exposure to the drug diethylstilbestrol (DES)
• History of orchitis or epididymitis in men
• Long-term (chronic) disease such as diabetes
• Pelvic inflammatory disease (PID)
• Many sexual partners
• Mumps (men)
• Sexually transmitted diseases
• Varicocele (men)

• A range of emotions by either or both members of the couple. In general, such reactions are greater among childless couples. Having at least one child tends to soften these painful emotions.
• Inability to become pregnant.

A complete history and physical examination of both partners is essential.

Tests may include:

• Blood hormone levels
• Cervical mucus to detect ovulation
• Endometrial biopsy
• Hysterosalpingography (HSG)
• Laparoscopy
• Luteinizing hormone urine test
• Pelvic exam
• Postcoital testing (PCT)
• Progestin challenge
• Semen analysis
• Serum progesterone
• Temperature first thing in the morning to check for ovulation (basal body temperature)
• Testicular biopsy (rarely done)