From Dr. Sarah Whitehead—Optimizing Your Chance of Becoming Pregnant, an Obstetrician’s View

Excited young couple view ultrasound of babyYou’ve decided you’re ready to start a family. In fact, you’ve decided that the next few months would be “ideal” to begin a pregnancy. But a month goes by, and then another, and no little + sign appears on the magic stick. You’re not exactly worried, nor should you be. Statistics say that around 20% of couples who will eventually have a spontaneous pregnancy do not conceive during the first six months that they attempt getting pregnant.  Obstetricians define infertility as the inability to achieve a successful pregnancy after twelve months of regular, unprotected intercourse. So, during this time we usually reassure young couples that most likely everything is normal. For older couples (beyond about 35) we may suggest some testing after about 6 months.

Still, you are just a little disappointed. Now and then, one of my patients in this situation will ask what she can do to “increase the chances” of becoming pregnant. It’s a good question. I am delighted to help you sort through the facts and myths that you’ve found on the Internet.

Fertility Facts

Your age affects the likelihood of a pregnancy. Women in their late 30s are about half as likely to become pregnant as women in their early 20s. Age affects men’s fertility too, but not as much as for women.

OK, but let’s consider the factors you have some control over. A common question is—more often or less often? Frequent intercourse does not decrease male fertility. In fact, some studies indicate that abstinence periods of greater than 5 days may decrease sperm counts. On the other hand, balance is important. The stress of “trying” may eventually reduce the frequency of intercourse for you. Best is what’s best for you as a couple. More frequent intercourse (every 1 to 2 days) may increase fertility, but not if it interferes with your relationship. This is especially true if you’re using ovulation predictors to choose your intimate moments.

That brings us to the question of “when?’ Intercourse is most likely to result in a pregnancy within the 3-day period before you ovulate. Some studies indicate that this peak of fertility occurs one to two days before ovulation. But predicting ovulation accurately is difficulty, even if your menstrual cycle is regular. In general, a woman’s “fertile window” will occurs within the week after her period ends (just an average). Ideally, you would try to have frequent intercourse during those days. This estimate of your fertility window should not be relied upon if you wish to avoid pregnancy.

Should you bring technology into your intimate life? There is very little reliable evidence that trying to accurately predict ovulation significantly improves the chance of getting pregnant. Precise timing of intercourse within the “fertile window” is probably not critical to success in any one cycle. But knowing approximately when ovulation occurs each month may result in an earlier successful pregnancy for couples who are unable to have intercourse frequently during those days. For couples wanting to monitor ovulation, changes in cervical mucous predict the fertile days about as well as more technical methods. Vaginal secretions increase and become more slippery and clear. These characteristics peak 2 to 3 days immediately before ovulation.

Having answered the question of when, couples sometimes wonder about how intercourse should occur. There is no convincing evidence that specific sexual practices or positions increase or decrease fertility. There is also no relationship between your position during intercourse and the sex of your baby. It would seem logical that a woman can prevent the leakage of sperm from the vagina by lying on her back for a time after intercourse, and thereby increase the chance of conception. But scientific evidence does not support this belief. Sperm has already travelled through the cervix within seconds after it is deposited in the vagina. On the other hand, some lubricants, and even saliva, seem to slow the movement of sperm in laboratory testing. If you find lubricants helpful, ask your doctor to recommend a product that does not have this effect.

preconception planning–talk with your ob/gyn

The last question—can you do anything else (besides frequent intercourse during your fertile days) to improve your chances for a pregnancy? Fertility rates decrease in woman who are either very thin or significantly obese. So, a program of reasonable weight management may be helpful, but no specific diet (vegetarian, low-fat, low-carb, etc.) has been shown to improve your chances of becoming pregnant. Likewise, no vitamin supplement, herbal remedy, anti-oxidant, or other supplement has been shown to improve fertility or to influence the sex of your baby. We do advise women to avoid a heavy seafood diet while trying to get pregnant. Fish contain varying amounts of mercury which—in sufficient quantities—can interfere with fertility. We recommend that reproductive-age women routinely take a supplement containing 400 mcg of folic acid.  Folic acid helps to prevent certain birth defects of the brain and spine. Having enough is so important that we recommend you begin taking a daily pre-natal vitamin containing 800 to 1000 mcg of folic acid as soon as you begin trying to become pregnant. 

Smoking has a substantial effect on fertility. Woman who smoke enter menopause 1 to 4 years earlier than nonsmokers. Smoking seems to speed up the natural loss of a woman’s eggs that occurs as she ages. Smoking also increases miscarriage rates. We cannot say for certain that moderate alcohol consumption reduces fertility, but heavier alcohol use (more than 2 drinks per day) should be avoided. And obstetricians strongly advise women to avoid alcohol altogether once a pregnancy has occurred. Moderate caffeine consumption (equal to 1 or 2 cups of coffee per day) should not reduce fertility for women or men.

We encourage you to see your Ob/Gyn physician if you are considering a pregnancy. Dr. Favor’s blog post on Preconception Health describes some of the issues we discuss at a preconception visit. We want to support your efforts to achieve a healthy pregnancy.