Getting Pregnant Naturally (29 page)

If you are among the one in three men or women of childbearing age who smoke cigarettes, do yourself a favor and quit. If you need another reason to kick the habit, consider the evidence supporting a link between smoking and infertility:

• Women who smoke have been found to be 3.4 times as likely as nonsmokers to take more than a year to get pregnant, according to a study of 678 women published in the
  Journal of the American Medical Association in 1985.
  

• A 1992 study in the British medical journal
  The Lancet
  found a 31 percent difference in fertility rates between nonsmoking couples and couples in which both the man and the woman smoked.
  

• Another study found that the fertility of light smokers (less than one pack—twenty cigarettes—a day) was 75 percent of that of nonsmokers; the fertility rate of heavy smokers (more than a pack a day) was 57 percent of that of nonsmokers.
  

• Doctors have known for many years that women who smoke during pregnancy tend to have smaller fetuses and shorter gestation periods than nonsmokers.
  

• Women who smoke during pregnancy miscarry more often. Women who smoke and do become pregnant are almost twice as likely to suffer miscarriage as women who don’t smoke, perhaps because smoking reduces estrogen levels.
  

• Even a relatively modest smoking habit can cut short a woman’s reproductive life. Women who smoke a half-pack of cigarettes a day experience menopause an
  average of one year earlier than nonsmokers, and those who smoke one pack enter menopause two years earlier.
  

• In men, as few as sixteen cigarettes a day can decrease sperm count and motility, increase the number of abnormal sperm, and make it less likely that the sperm will fertilize an egg. Evidence also exists that babies born to men who smoke are more likely to have birth defects. The most vulnerable time for smokers is the three-month period before conception when the sperm is being produced.
  

• Smoking saps the body of fertility-enhancing vitamin C, which appears to be one reason for the reduced sperm count among male smokers. Evidence indicates that smokers require at least twice as much vitamin C as nonsmokers. In one study, men with a pack-a-day habit were given either 0 milligrams, 200 milligrams, or 1,000 milligrams of vitamin C. After one month, the men in the 1,000-milligram group had a 140 percent increase in sperm count; those in the 200-milligram group had a 112 percent increase, and the men in the 0-milligram group had no change. More to the point, all the men in the vitamin C group got their partners pregnant within two months, while none of the men in the placebo group had conceived a child. If you smoke, take up to three grams of vitamin C a day (any your body doesn’t need will be excreted in your urine).
  

• Be wary of secondhand smoke. Standing in a very smoky room for one hour will be as toxic to your lungs—and your fertility—as directly inhaling ten to fifteen cigarettes.
  

Drinking alcohol—even in moderation—can affect the fertility of both women and men. In women, alcohol affects the liver’s ability to clear hormonal debris, disrupting hormone levels and interfering with egg production. While the amount of alcohol required to alter brain chemistry and hormone levels varies from woman to woman, evidence suggests that even moderate drinking can contribute to infertility. A 1994 study involving women who used alcohol moderately (one drink or less per day) found a strong correlation between drinking and ovulatory dysfunction and endometriosis. This was after adjustment for age, cigarette smoking, number of sexual partners, use of an intrauterine device, body mass index, and level of exercise.

In men, drinking three drinks a day can cause endocrine abnormalities, low testosterone levels and sperm counts, and an increase in abnormal sperm. Extreme alcohol use (more than five drinks a day) can cause impotence,
as well as a temporary inability to ejaculate if an erection does occur.

Recent studies have found that the babies of fathers who drank as few as two drinks a day in the month prior to conception weighed 6.5 ounces less than the babies of teetotaling fathers. This link had nothing to do with whether the mother drank or smoked.

There are plenty of good reasons not to use illegal drugs, and inhibiting fertility is just one of them.

• Marijuana carries all the risks and negative side effects of cigarette smoking—and more. Tetrahydrocannabinol (THC), the primary psychoactive ingredient in marijuana, reduces the size of the uterus and ovaries in women; it lowers hormone levels and disrupts menstruation and ovulation. (Female marijuana smokers are three times more likely than nonusers to have irregular menstrual periods.) In men, marijuana use is linked to lowered sperm counts and chromosomally damaged sperm. Smoking marijuana also decreases the male sex drive.
  

• Cocaine causes birth defects and can trigger miscarriage by stimulating the nervous system, increasing blood pressure and heart rate, and constricting blood vessels. In men, cocaine can raise the core body temperature
  and damage sperm; it can also cause hormonal imbalances that affect sperm production.
  

• Hallucinatory drugs, amphetamines, barbiturates, and narcotics all interfere with hormone levels in both men and women, interfering with ovulation in women and sperm production in men.