How Often And When Should You Have Sex During Your Fertile Days?

When and how often should we have sex?

When trying to get pregnant, how often should you have sex? Every day or every other day? And when in relationship to ovulation? Wait for the ovulation predictor kit (OPK) to become positive? Or when the basal body temperature goes up? 

Make love every 1-2 days during the 5-6 days of the fertile window

To improve your chances of getting pregnant, you need to make love on your fertile days. You only have 5-6 fertile days each cycle, the 4-5 fertile days before and the day of ovulation. Making love more than 5 days before the day of ovulation or making love the day after ovulation will not get you pregnant. Your chances of getting pregnant improve if you make love every day during your six most fertile days. 

Timing Intercourse

Timing intercourse is when you try to make love only once or twice and then only when you think you could be oivulating, within a day or two of ovulation. The problem with timing is that has never been shown to improve your pregnancy chances. In addition, many women often do not know the exact day that they will ovulate and studies have shown that even in women with regular cycles, ovulation can possibly happen any time.

You are probably not improving your chances of getting pregnant if you wait for intercourse until the ovulation predictor kit has become positive. The problem with the OPK is that by the time it's positive you may already have ovulated, and sex after ovulation is unlikely to get you pregnant. Waiting until the BBT temperature has gone up is even worse, as the temperature goes up after ovulation.

On which days of my menstrual cycle am I more likely to get pregnant?

According to research, here are your chances of getting pregnany if you have sex only once during your fertile window:

  • 6 days before ovulation (-6 dpo) : 0 %
  • 5 days before ovulation (-5 dpo) : 8 %
  • 4 days before ovulation (-4 dpo) : 17 % 
  • 3 days before ovulation (-3 dpo) : 8 %
  • 2 days before ovulation (-2 dpo) : 36 %
  • 1 day before ovulation (-1 dpo) : 34 %
  • The day of ovulation (dpo) : 36 %
  • Any day (24+ hours) after ovulation: (1+ dpo) : 0%

Adapted from Wilcox, AJ. et al. NEJM (1995)

Wilcox NEJM 1999

Frequency of Intercourse

Couples who tried to get pregnant were previously told to have sex once every other day during their fertile days. But studies have shown you can improve your chances if you have sex once a day, every day (as long as his sperm are OK) during the fertile 4-5 days prior to, and including the day of, ovulation. In those rare circumstances when the man does not have enough sperm (oligospermia), the old rule of once every other day still holds true.

In addition, researchers recommend that the average couple who is trying to conceive should make love regularly 2-3 times a week, every week because you don't know exactly when ovulation happens.  

Frequency and Pregnancy Chance

Sex during fertile days   % Pregnancy
Sex every fertile day 37%
Sex every other fertile day 33%
Only once during fertile days 15%

Source: The New England Journal of Medicine (December 7, 1995 -- Vol. 333, No. 23). Allen J. Wilcox, Clarice R. Weinberg, Donna D. Baird