Infertility is defined as the inability for a couple to become pregnant after a year of unprotected intercourse. The male partner, the female partner, or both may have a fertility problem. A person who is infertile has a reduced ability to have a child. It usually doesn’t mean a person is sterile — that is, physically unable ever to have a child.
For many couples, infertility is a crisis. Fertility problems often come with feelings of guilt or inadequacy. Up to 15% of all couples are infertile, but only 1% to 2% are sterile. Half of couples who seek help can eventually bear a child, either on their own or with medical assistance. Men and women are equally likely to have a fertility problem. In about 1 in 5 infertile couples, both partners have contributing problems, and in about 15% of couples, no cause is found after all tests have been done, called “unexplained infertility.”
What Causes Fertility Problems in Men?
In men, the most common reasons for infertility are sperm disorders. These problems include:
- Low sperm count. This means there are too few or no spermatozoa in the semen.
- Low sperm motility. This means that the sperm don’t move as well as they should.
- Malformation of the sperm.
- Blocked sperm ducts.
Another common problem is a temporary drop in sperm production. This happens when the testicles have been injured, such as when the testicles have been too hot for too long or the man has been exposed to chemicals or medications that affect sperm production. Spending a long time in a hot tub, for example, or wearing underwear that holds the testicles too close to the body can increase the testicular temperatures and impair sperm production.
Sometimes there is a physical reason. In the relatively common condition called varicocele, veins around the vas deferens (the duct that carries sperm from testicle to urethra) becomes dilated — similar to a varicose vein in the leg. The pooling of blood in these veins keeps the temperature inside the scrotum too high.
Certain lifestyles, like increased alcohol intake and smoking, can also have a negative effect on sperm count. Men who are 40 or older often have decreased fertility.
What Causes Fertility Problems in Women?
Anovulation, or lack of ovulation (release of eggs from the ovary) is the primary reason for infertility in women. The major cause of anovulation is a condition called polycystic ovary disease, or PCOS.
Another reason for female infertility is the inability of the fallopian tubes to carry eggs from the ovary to the uterus, usually due to scar tissue that may have resulted from prior infection or from a condition called endometriosis.
Rarely, in the uterus, fibroid growths, endometriosis, tumors, cervical problems, or irregular uterine shape can keep the egg from implanting in the uterus.
Fertilization may not happen if the cervical mucus damages sperm or impedes their progress.
Age is a major factor of female infertility. In women, fertility declines with age, and even more so after the age of 35. Conception after age 45 is rare. Being overweight or underweight can also play a role in having trouble getting pregnant.
Evidence suggests that couples trying to get pregnant should see a doctor for a periconception visit as soon as they start trying to conceive. This is especially important for couples with medical issues. During the periconception visit, they can explore whether there are any problems that should be treated to improve fertility and increase their chances of getting pregnant and having a healthy baby.
Women trying to conceive should add a supplement of at least 600 mcg folic acid, either alone or as part of their prenatal vitamins, to decrease the risk of fetal malformations. Folic acid may also decrease the risk of a miscarriage. The folic acid supplement should be started at least 1 to 2 months prior to conception to maximize its efficacy.