Infertility
In this condition factsheet:
The Facts on Infertility
Infertility is usually defined as the inability to become pregnant after 1 year of vaginal intercourse without birth control. Without contraception, frequent intercourse results in pregnancy for 50% of couples within 3 months, 75% of couples within 6 months, and 90% of couples within 1 year.
Infertility affects about 1 in 6 Canadian couples. While it was often considered only a woman’s problem, both men and women can contribute to infertility. In about a third of couples with infertility, a male factor is identified along with a female factor.
People shouldn't assume that they or their partners are infertile until they've tried and failed to conceive for at least 6 months if the female partner is 35 years or older, or for at least 1 year if the female partner is less than 35 years of age. If you are still unable to get pregnant after this time, check with your doctor. You may want to see your doctor after 6 months of trying to get pregnant if the female partner has an irregular menstrual cycle or known reproductive abnormalities, or if the male partner is known to have fertility issues. Fortunately, it's not uncommon for couples to suddenly conceive a child after years of trying unsuccessfully without treatment.
Causes of Infertility
Infertility in both women and men can be caused by a variety of medical conditions and problems.
Causes of infertility in women include:
- age
- chlamydia and other sexually transmitted infections (STIs)
- damaged ovaries
- blocked fallopian tubes
- hypothyroidism (a thyroid disorder)
- endometriosis (a condition where cells from the womb lining are found outside the womb)
- polycystic ovary syndrome
- scarring in the uterus
- fibroids (benign tumours of the uterus)
- congenital diseases like cystic fibrosis
- excessive exercise (leading to missed menstrual periods)
- anorexia or bulimia
- frequent changes in weight
- damage to the cervix (e.g., through an abortion or dilatation and curettage [D&C])
- hyperprolactinemia (higher than normal levels of the hormone prolactin in the blood)
- untreated celiac disease or other autoimmune condition
Infertility may seem more common these days because more people are choosing to have children later in life. But because female fertility decreases with age, women in their late 30s and early 40s naturally have a harder time conceiving, even with treatment. Although 25% to 50% of women dealing with infertility are found to have at least some traces of endometriosis upon examination, it is not known in some cases if this is the cause of the infertility.
Some women suffer repeated miscarriages, which are often due to immune problems, genetic problems, hormonal problems, or occasionally, a uterus that is slightly misshapen. Occasionally, the man's sperm is unable to penetrate the woman's egg, but there is a treatment for this which requires in-vitro fertilization (IVF).
Hyperprolactinemia is another possible cause of infertility in women. This is an excess of the hormone prolactin, which normally stimulates breast milk production in women. High prolactin levels can interfere with ovulation and menstruation. Stress, marijuana, and hypothyroidism are among the factors believed to contribute to high prolactin levels. Certain prescription medications can also cause an elevated prolactin level. Rarely, it may be caused by a very small tumour in the pituitary gland of the brain that is easily treated with medication.
Women may also be concerned that having used birth control pills, vaginal rings, patches, and injections could possibly make them less fertile after they have stopped using them. There is no evidence that using birth control pills, vaginal rings, or patches increases the risk of infertility; however, you may want to delay trying to get pregnant for at least one menstrual cycle after stopping these medications. This is to help you get the cycle restarted even though your periods were regular when you were using these birth control methods. However, if you had irregular or infrequent periods before you began taking birth control pills or any one of these hormonal methods of birth control, your periods are likely to go back to the way they were. That is, if you were having periods every 1 to 2 months or so, the pattern will restart itself and return.
Using intrauterine devices (IUD) has also not been shown to increase the risk of infertility in women. Some women who use injection birth control methods (progesterone injections) may notice that it may take almost a year for their periods to restart and for fertility to return. Talk to your doctor or pharmacist about whether infertility may result from your method of birth control and if so, how long this time may be.
Causes of infertility in men include:
- hormone disturbance
- smoking
- overheating of the testicles caused by exercise, hot water, tight clothing, excessive sitting (truck drivers) and other conditions and situations
- cancer medications and radiation therapy
- mumps after puberty
- STIs
- anatomical abnormalities of the genitals such as undescended testicles
- use of some medications, such as some for high blood pressure, some antidepressants, and male hormones
- genital injury
- prostate surgery
- varicose veins in the testicles
- excessive alcohol
- intercourse problems such as premature withdrawal or poor timing with their partner's menstrual cycle
- spinal cord injury
- genetic abnormalities
- urinary tract infection
- cystic fibrosis
- illicit drug use (e.g., using cocaine, smoking marijuana)
- opiates
- steroids
- pesticide exposure
Some men are more prone than others to infertility problems. These factors contribute to the risk of infertility:
- diabetes
- poor nutrition
- smoking (lowers sperm count and reduces erections)
- hot baths
- being very overweight or underweight
The environment may also affect fertility. Sperm counts are going down in industrialized countries due to unknown environmental factors.
Types of male infertility include:
- azoospermia – no sperm in the ejaculate
- oligospermia – low concentrations of sperm in the ejaculate
- asthenospermia – sperm are present but can't swim normally
- teratospermia – high proportion of abnormally-shaped sperm
- retrograde ejaculation – the tube through which sperm normally travel is blocked and sperm may end up in the bladder
Symptoms and Complications of Infertility
A young, reproductively healthy couple who isn't using contraception has roughly a 20% chance of conceiving in any given month. If someone is young and has no reason to think they might be infertile, they should try for up to a year before considering consulting a physician regarding some kind of infertility treatment. If the female partner is over 35, most fertility specialists recommend seeking treatment after 6 months, so that the chances can be improved while the woman is still young enough to be fairly confident of a problem-free pregnancy.
