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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 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.