Every one to two days during the fertile window, and every two to three days across the rest of the cycle. That is the American Society for Reproductive Medicine's committee opinion on optimizing natural fertility, and the NHS puts it as sex every 2 to 3 days. Saving up does not help: in a 2016 study, 20 men who ejaculated daily for two weeks saw volume, concentration and total motile count fall over the first three days and then hold steady, with motility and morphology unchanged. A 2025 meta-analysis of 22 studies and 31,640 samples found that abstaining for two days or less, compared with the standard 2 to 7 days, meant about 8 million per mL less concentration and 0.8 mL less volume, but 2 percentage points more progressive motility and 4 points less DNA fragmentation. Frequency changes what is in a sample within days; it does not change the 74-day cycle that makes sperm.
What the guidance says
The ASRM committee opinion (Fertility and Sterility, 2022) reviews the evidence on timing and concludes that intercourse every one to two days during the fertile window, the five days before ovulation plus ovulation day, gives the highest chance of pregnancy per cycle, and that every two to three days at other times is reasonable. The NHS puts the general advice as: if you are aged 39 or under and have sex without contraception every 2 to 3 days, it is likely you will get pregnant within a year. Neither body recommends abstaining to build up a sample, and both have moved away from the older advice to save it for ovulation.
What daily ejaculation does to a sample
Welliver and colleagues (Translational Andrology and Urology, 2016) had 20 healthy men ejaculate every day for 14 days and analyzed every sample. Semen volume, sperm concentration and total motile count all fell, mostly during the first three days, and then leveled off for the rest of the fortnight. The share of motile sperm and the share of normally shaped sperm did not change. Each daily sample carried fewer sperm than a rested one, but the sperm were the same quality, and the supply did not run out: after the initial drop the men produced a steady daily output. The old picture of a reservoir that needs days to refill does not match the data.
Short abstinence versus long
Raditya and colleagues (World Journal of Men's Health, 2025) pooled 22 studies and 31,640 semen samples comparing abstinence of two days or less with the WHO's standard 2 to 7 days. Short abstinence meant lower semen volume (0.83 mL less) and lower concentration (8.4 million per mL less), but higher progressive motility (2.2 percentage points), higher total motility (2.3 points) and lower DNA fragmentation (3.8 points), with morphology unchanged. An earlier systematic review of 28 studies (Hanson and colleagues, 2018) reached a more cautious verdict: volume and count rise with longer abstinence, motility, morphology and DNA fragmentation tend to improve with shorter, and "no clear recommendations can be made regarding ideal abstinence" because the studies conflict. Read together: longer gaps buy more sperm per ejaculate, shorter gaps buy fresher ones, and neither side of that trade is large.
Why saving up doesn't help
Sperm that sit in the epididymis for a week are older, and the DNA fragmentation figures above are the measurable sign of that. Meanwhile the chance of conception in a cycle depends on there being sperm in the right place across the fertile window, not on a single large deposit on one day. Frequent sex covers the window; abstaining to time one attempt tends to miss it. That is the logic behind the every-one-to-two-days guidance, and the studies of short abstinence show it costs nothing in sperm quality.
Before a semen analysis
A lab test is different from trying to conceive. The WHO manual asks for 2 to 7 days without ejaculation before the sample, because the reference limits were set on samples collected that way; a one-day gap will read low on volume and count, and a two-week gap will read low on motility, and both will be compared with the wrong reference. Pick a number in the range, use the same number for the retest, and tell the lab what it was. The retest guide covers the rest of keeping two tests comparable.
Does it change the 74-day cycle?
No. Ejaculation frequency changes which sperm are in a given sample and how many, within days. Production runs continuously on its own clock of about 74 days, and the lifestyle factors on this site act on that. Frequency is the one lever that moves a sample this week; everything else moves the sample in three months. The how-long guide explains the cycle.
What to do
- During the fertile window, aim for every day or every other day. The five days before ovulation plus the day itself are the window.
- Outside it, every two to three days keeps the supply fresh and covers an ovulation that comes early or late.
- Don't abstain to build up a sample for trying. The evidence says it costs freshness and gains little.
- Before a semen analysis, abstain for 2 to 7 days, use the same gap for the retest, and tell the lab.
- If your partner shares her fertile window in the Motily app, it appears on your Today tab; log intercourse there and the timing takes care of itself.
Related guides
Sources
- Practice Committee of the American Society for Reproductive Medicine. Optimizing natural fertility: a committee opinion. Fertility and Sterility, 2022.
- NHS. Trying to get pregnant.
- Welliver C, et al. Analysis of semen parameters during 2 weeks of daily ejaculation. Translational Andrology and Urology, 2016.
- Raditya M, et al. Impact of shorter abstinence periods on semen parameters: a systematic review and meta-analysis. World Journal of Men's Health, 2025 (online 2024).
- Hanson BM, et al. The impact of ejaculatory abstinence on semen analysis parameters: a systematic review. Journal of Assisted Reproduction and Genetics, 2018.
- World Health Organization. WHO laboratory manual for the examination and processing of human semen, 6th edition. 2021.
- Chung E, et al. Sixth edition of the World Health Organization laboratory manual of semen analysis: updates and essential take away for busy clinicians. Arab Journal of Urology, 2023. (Abstinence of 2 to 7 days.)
- Heller CG, Clermont Y. Spermatogenesis in man: an estimate of its duration. Science, 1963.