How often do you need to have sex to have the best chance of getting pregnant?

One of the most frequent problems we see as primary care physicians is couples having trouble trying to conceive. As a doctor, something that I find most gratifying is when I do a 6-week baby check having several months before having a consultation with the parents about how to optimize the chance of conception. Most good doctors, when advising couples on getting pregnant, will take a careful medical and lifestyle history to find out if there are any easily modifiable factors that may when addressed lead to an improvement in fertility. Thankfully, most of the time it really is just a matter of time before a couple conceives and the influence doctors have very little to do with it. Statistics show that 84% of couples having regular (at least three times per week) sexual intercourse will conceive within one year and 92% of couples within 2 years. 

The birds and the bees

An aspect that many couples find confusing is advice regarding the frequency and timing of sexual intercourse. There are innumerable sources of advice available but many lack quality of evidence or are confusing or contradictory. Knowledge of a few pointers of reproduction can help. Ovulation usually occurs 12 to 16 days before the first day of the next period. The egg lives for about 24 hours. Sperm can survive for up to 7 days. Therefore, for most couples ‘The Fertile Window,’ when the viability of sperm and the egg are at their highest, are the 6 days up to and including the day of ovulation. In terms of timing, the optimum time to have sex is 2 days before ovulation. A common mistake couples make is starting too late in the cycle.

Little Soldiers

A commonly held misconception (no pun) is that frequent ejaculations reduce semen quality. In fact, surprisingly, the opposite is the case. A study in 2005 that examined nearly 10,000 semen samples from men who were undergoing investigation for infertility found that even with daily ejaculation sperm concentration and movement remain normal. The same study found that optimal semen quality was found with no or only one day of abstinence from intercourse even in men who had low sperm counts.

The most recent guidelines on fertility in the UK from NICE (National Institute of Clinical Excellence) advise couples to have intercourse every 2-3 days. This advice on the optimal frequency of intercourse to conceive is based on more vintage studies from 1953 and 1962. These studies suggest that frequent ejaculations might reduce sperm number and movement capability. However, as we have already seen, it has been shown that this is not the case. In addition, another study published in the New England Journal of Medicine also found no evidence that couples trying to conceive should in any way limit their frequency of intercourse. In fact, this study demonstrated that daily sex results in the highest chance of getting pregnant. This is the bottom line. Daily intercourse gives the highest chance of getting pregnant. 

Don’t Stress

Trying to get pregnant can be a stressful time and many couples wonder whether it will ever happen.  In particular, intercourse set at a specific time can become stressful and feel contrived. The stress of trying to get pregnant can actually reduce not only satisfaction but also frequency. This is why ovulation predictor kits which require couples to follow a strict schedule can be counter-productive. The most important advice that I could give about trying to conceive is to make a big effort to enjoy the process. Make it fun and exciting. Once you have your newborn at home with you the opportunities for this kind of excitement are considerably less. So make the most of it.

If you can only manage every two days that is fine as the likelihood of success was almost as good compared to daily intercourse. Leaving it three days without intercourse on the basis of data from 69-year-old studies is more likely to result in a feeling that you are on a strict schedule and make the process less fun. Some couples might find that having frequent sex is stressful in itself and for these couples, ovulation predictor kits may offer a more useful guide.

Let there be cuckoos…

More frequent intercourse gives a higher chance of pregnancy and does not adversely affect the quality of semen. So don’t worry about delaying intercourse for three days during the narrow fertile window of 6 days as the guidelines suggest. Throw the ovulation predictor kit in the bin. Do all your going out for dinner, sleeping, and cinema trips (once COVID restrictions are lifted) while you can….. but most of all, please….. let there be love.

Dr. Hugh Coyne

Private GP Parsons Green