Chance of getting pregnant 3 days before ovulation

So you've made the big decision -- you're going to start a family! But while you were certain that getting pregnant would be fast and easy, after six months of trying it's just not happening.

Could something be wrong? Of course that's always a possibility. But if you are young (between 18 and 34) and you and your partner are generally healthy, doctors say more often than not some simple problems -- with easy fixes -- may be standing in your way.

Among the most common: Miscalculating your most fertile time of the month.

"By far, the single most important thing stopping healthy couples from getting pregnant is they are not having intercourse at the right time -- and the reason for that is many women simply aren't calculating their ovulation time, or most fertile period, correctly," says Steven Goldstein, MD, professor of obstetrics and gynecology at NYU School of Medicine in New York City.

Goldstein says that, while most women know they must ovulate in order to conceive, many don't realize that waiting for this to happen before having sex causes them to bypass their most fertile time.

"After ovulation, an egg is only viable for about 24 hours -- so if you are waiting until you ovulate to have intercourse, chances are you are going to miss the opportunity to get pregnant that month," says Goldstein.

Since sperm can live in your reproductive tract for up to 72 hours, doctors say having sex beginning at least three days before ovulation dramatically increases your chance of conception.

"I tell my patients to start having sex a full five days before they expect to ovulate -- this way even if they are off a day or two in calculating their ovulation, the bases are still covered. It's better to have sex too early, than too late," says Sharon Winer, MD, an obstetrician at Cedars Sinai Medical Center in Los Angeles.

Indeed, a 10-year study published in the New England Journal of Medicine in 1997 found that having sex beginning six days prior to ovulation is the most conducive to achieving conception. In the same study, not one pregnancy occurred when sex took place 24 hours after ovulation.

But how do you know when you are about to ovulate? Goldstein tells WebMD you should keep an accurate menstrual calendar, tracking your period for at least two or three months prior to when you want to conceive.

"Ovulation takes place 14 days before you get your period, so you need to keep an accurate calendar for a couple of months, marking down when your period arrives -- and day one is always the first day of bleeding," says Goldstein.

Then, he says, when you are ready to get pregnant use the calendar to predict when your next period will arrive, and simply count back 14 days from that date. "This will be your projected ovulation date -- and you should begin having sex several days prior to that date, " says Goldstein.

But what if your periods aren't regular?

" If your cycle is irregular, between 26 and 29 days, for example, then you are probably ovulating somewhere between day 12 and day 15," he says.

In this instance, Goldstein says consider having sex from day nine through day 16.

"If you have sex every other day, start on day 9, then have it on 11, 13, 15, and 16 for the highest likelihood of conception," says Goldstein.

To help you further hone in on your most fertile time, both Goldstein and Winer say ovulation predictor kits can help. But, says Winer, be certain to read the directions carefully, since every kit works a little differently in terms of how and when it predicts ovulation and that can influence the timing of intercourse.

Because a rise in body temperature also correlates with ovulation, many couples use daily temperature readings to guide them to the right time for conception. However, experts warn that most don't use the information correctly, and also wind up missing their pregnancy opportunity month after month.

"Many couples believe they should have sex when a woman's temperature rises; and throughout the years, many situation comedies and movies have perpetuated that myth," says John F. Randolf, Jr. MD, division director of reproductive endocrinology and infertility at the University of Michigan Health System.

In truth however, Randolf tells WebMD that, once your temperature goes up, it's probably already too late -- and your chances of getting pregnant are slim.

"The correct way to use body temperature to predict ovulation is to keep a daily chart for at least one or two months -- then use that information to determine when your temperature is likely to rise the next month, and start having sex several days prior to that," says Randolf.

And how often should you "try" to conceive and can there ever be "too much sex?"

Since it is sperm and not egg that is affected by the frequency of intercourse, for a long time doctors believed that having sex every day might decrease sperm count, making pregnancy more difficult. Today experts are less concerned.

"I think the more times you have intercourse during your 'window of opportunity,' the more likely you are to get pregnant. I don't think you should worry about having too much sex when you are trying to conceive," Winer tells WebMD.

The same 1997 the New England Journal of Medicine study cited previously found that having sex every day is slightly more likely to result in pregnancy than intercourse every other day.

However, experts do caution couples not to put their love making on a schedule. That, they say, just might decrease chances of conception.

"The scientific evidence is scarce, but when you are stressed, when love making is on 'schedule,' there is some data to show that hormones may be affected, and that in turn could influence conception," says Goldstein.

In a study conducted at Harvard Medical School on 184 women with fertility problems, 55% of those who completed a 10-week course of relaxation training, and stress reduction had a viable pregnancy within one year, compared with just 20% of the group who had no stress reduction training.

In a second study conducted at the University of California at San Diego, doctors found that women undergoing fertility treatments, who remained relaxed and optimistic, had better overall outcomes than women who were pessimistic about their ability to conceive.

"If you are worried all the time about getting pregnant, if you obsess over it and think about only that, you might influence your body chemistry in a way that does affect your fertility," says Randolph. The key, he says, is to "think about making love -- and not just about making babies."

So you say you're relaxed, you're having sex at all the right times and you still can't get pregnant? Doctors say try pillow therapy!

"This involves propping your pelvis up on pillows after you have intercourse, and lying in bed for at least 20 to 30 minutes after sex, to facilitate the movement of sperm through your reproductive tract," says Goldstein, who says that he's a firm believer in this tenet as an important pregnancy aid.

What probably won't make a difference, however, are the position you are in when you have sex, that is, unless you're standing up at the time.

"As long as you are lying down -- so sperm can't run out of the vagina -- then the position is probably not going to make all that much difference, particularly if you do remain in bed with your pelvis propped up afterwards," says Goldstein.

Conception Misconceptions

As easy as it might be for some women to get pregnant, doctors say there are also some common "myths" about conception, which, for some couples, could make it harder to conceive.

One such notion is that using a lubricant makes it easier for sperm to slip slide and get inside. Not only is this not true, it could actually prevent you from getting pregnant.

"Most lubricants can change the pH or acid balance inside the vagina, and that in turn may affect sperm motility and ultimately prevent, or at least reduce the chances of a pregnancy occurring," says Goldstein.

If you find you must use a lubricant avoid petroleum jelly. It's just too sticky he says. Instead he advises trying a natural vegetable product, such as olive oil, which is less likely to cause sperm any serious problems.

Winer also cautions women to avoid douching, either prior to, or especially after intercourse, citing possible changes in the vaginal environment that could negatively impact sperm.

As to the boxers vs. briefs controversy -- the idea that wearing loose boxer shorts instead of tight briefs may help a man's fertility, mostly by keeping their sperm-making apparatus cool and comfortable. Randolf says this is simply an "old husband's" tale. The type of underwear your partner wears is of little consequence, he says.

Finally, many women are concerned that coming off the birth control pill might affect their ability to get pregnant, but doctors say that generally there is little to worry about.

"The only issue with birth control pills is making sure you have at least one normal menstrual period prior to trying to conceive, which is important for the dating of the pregnancy," says Winer.

As far as safety goes, Goldstein says the steroids used in the pill are out of your body within a week or less -- so they won't affect your baby or stop you from getting pregnant.

"You may need to be off the pill for a few months in order to regulate your menstrual cycle and begin ovulating, but otherwise, once you stop using the pill, it should have no residual effects on your ability to get pregnant, " says Goldstein.

If, in fact, you are between the ages of 18 and 30 and you and your partner are relatively healthy and having regular intercourse, particularly during your most fertile times, doctors say you should conceive within 12 months or less. If more than a year goes by and you are not pregnant, check with your gynecologist about whether or not you or your partner could benefit from fertility testing.

Colette Bouchez is the author of Getting Pregnant: What You Need To Know and the forthcoming book Your Perfectly Pampered Pregnancy.