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About this tool
Score nineteen heat, substance, sleep, nutrition and timing habits linked to sperm quality, and get a review date.
Male Fertility Lifestyle Checklist scores nineteen habits with published links to semen quality — scrotal heat exposure, smoking, alcohol and cannabis, body weight, sleep, diet, ejaculation timing and occupational toxins — weighting each by how consistent the evidence is. Because one cycle of human spermatogenesis takes about 74 days plus roughly two weeks of epididymal transit, it also sets a review date about 88 days out, when a change could realistically show up in a semen analysis. It scores habits, not fertility: only a semen analysis interpreted by a clinician does that.
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Smoking, anabolic steroid use and body weight carry more weight than saddle time, because the data does.
Sets the re-test date one full 88-day sperm cycle ahead instead of encouraging a pointless early re-test.
Shows the 2021 sixth-edition reference limits so a lab report is easier to read.
About three months. One cycle of spermatogenesis takes roughly 74 days, and sperm need a further two weeks to travel through the epididymis, so a semen analysis repeated sooner than about 88 days will still reflect the old habits.
Yes. The testes normally sit around 2 °C below core body temperature, and repeated wet heat — hot tubs, saunas, very hot baths — has been linked with lower sperm concentration and motility, with recovery over three to six months after the exposure stops.
The WHO 2021 lower reference limits are 16 million sperm per mL, 39 million total per ejaculate, 42% total motility, 30% progressive motility and 4% normal forms, from a semen volume of at least 1.4 mL. These are 5th centiles of fertile men, not a pass or fail line.
Every one to two days across the fertile window — the five days before ovulation plus the day itself — works better than saving up for a single day. Long abstinence raises volume but reduces motility and DNA integrity. If you have been trying for 12 months, or 6 months when the female partner is over 35, both partners should be assessed.