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Does more frequent intercourse improve sperm quality?

How often should we have intercourse to get pregnant? | Princeton IVF blog

Abstinence and sperm quality

For years, fertility specialists and gynecologists have been encouraging couples to limit sexual intercourse in order to maximize their chances for pregnancy. Some doctors advise their patients their patients to try daily at ovulation time, while many others advise intercourse ever other day. For semen analysis, an even longer period of abstinence is recommended. The presumption behind these recommendations is that frequent intercourse is harmful to semen quality. It turns out that this assumption may not be true.

Research from the UK suggests abstinence may not improve sperm

A study presented at the European Society of Human Reproduction and Embryology by doctors at the North Middlesex Hospital looked at using a second sperm sample (instead of the first) for IUI (intrauterine insemination) cycles. The specialists at the clinic started out using the first semen sample of the day, and then later in the study had the men produce a first sample, and then produce a second sample an hour later. That second semen sample was used to perform the IUI. What they found next was unexpected. Pregnancy rates increased between 2 and 3 fold by using the second sample.

Will this change the practice of fertility medicine?

Possibly, but not likely. If this technique is able to improve success rates with IUI, given the lower cost of the procedure, more physicians and patients could ultimately chose to go with IUI. However, first the findings will need to be replicated elsewhere and the technique of using the second sperm sample demonstrated to be more effective in much larger studies. It is also not clear whether the improvement is pregnancy rates was mainly due to changes in the fertility drugs used with the IUI. Even if this method proves to be more effective, IUI still will never be as effective as IVF. 

Will this change doctors recommendations for intercourse frequency?

It may very well. This study suggests that more frequent ejaculation may improve sperm quality. Even if abstinence is not beneficial, it likely that more frequent intercourse is at the very least not harmful. The recommendations that couples abstain for a period prior to IUI or IVF may become outdated. However, it is not correct to assume that just because abstinence may not be helpful for insemination cycles, that it not helpful for natural conception either.