How to Prepare for a Semen Analysis: Abstinence, Collection and Timing

Two to seven days. That is the window specified in the WHO laboratory manual, now in its sixth edition (2021), and it is what laboratories calibrate their reference ranges against.

The range exists for a practical reason rather than a biological one: it is wide enough to fit around normal life while narrow enough to keep results comparable between men and between laboratories.

Staying inside it matters because abstinence changes the numbers in opposite directions:

• Longer abstinence, roughly 4 to 7 days and beyond — raises semen volume and total sperm count, but motility falls and DNA fragmentation rises
• Shorter abstinence, around 2 days or less — lowers volume and count per ejaculate, but motility and DNA integrity are better

So a sample taken after ten days may look better on count and worse on motility, and one taken after twelve hours the reverse. Neither reflects your actual fertility; both make the result hard to interpret against reference values.

If you are asked to repeat the test, use the same abstinence period as the first time. Comparing two samples collected after two days and nine days tells you very little.

Most avoidable errors happen here rather than in the days beforehand.

1. Collect by masturbation, into the sterile container the clinic provides
2. Collect the whole ejaculate, including the very first drops
3. Note the exact time of collection — the laboratory needs it
4. Deliver within 30 to 60 minutes, keeping the container close to body temperature
5. Tell the laboratory if any part of the sample was lost

The first fraction point is the one most often missed. Sperm are not evenly distributed through the ejaculate — the first portion carries the highest concentration. Losing it can make a normal sample look severely abnormal.

What not to use:

• Ordinary lubricants, saliva, or soap — many are toxic to sperm
• Standard condoms — most are coated with spermicide; if collection during intercourse is necessary, the clinic can supply a special non-toxic collection condom
• Withdrawal — the first fraction is routinely lost

Collecting at the clinic avoids the transport and temperature problems entirely. If you collect at home, ask how far away is acceptable before you book.

Much less matters here than the internet suggests, but a few things genuinely do:

• Report any fever in the previous three months — sperm take roughly 74 days to develop, so an illness two months ago can still show in today's result
• Tell the clinic about all medication, including testosterone, anabolic steroids, finasteride, chemotherapy, and some antibiotics
• Avoid heavy alcohol in the days before
• Skip the sauna, hot tub, and very hot baths in the run-up

Supplements started a week ago will not have changed anything measurable. The production cycle is about two and a half months, so any real effect of a lifestyle change shows on a test taken roughly three months later, not three weeks.

Semen parameters vary substantially in the same man from week to week. That variation is normal biology, not laboratory error.

Because of it, a single abnormal result does not establish a diagnosis. A confirmatory second sample, usually a few weeks later, is standard practice before any conclusion is drawn.

Two further points about interpretation:

• WHO reference values are the fifth centile of men whose partners conceived within 12 months — they are a statistical cut-off, not a threshold for fertility
• Results slightly below a reference limit do not mean conception is impossible, and results above it do not guarantee anything

A result should be read alongside your history and your partner's assessment, not on its own.

Knowing what is being assessed makes the preparation rules make sense.

A basic semen analysis reports:

• Volume — how much fluid, in milliliters. Mostly seminal vesicle and prostate secretions rather than sperm
• Concentration — sperm per milliliter
• Total sperm number — concentration multiplied by volume, and generally more meaningful than concentration alone
• Motility — the proportion moving, graded by how well they move
• Morphology — the proportion with normal shape, assessed against strict criteria
• Vitality — the proportion alive, checked when motility is very low
• pH, appearance, liquefaction time, and white blood cells

The WHO sixth edition reorganised these into basic, extended and advanced examinations. Extended tests, such as DNA fragmentation, are used in specific situations rather than routinely. Advanced tests remain largely research tools.

Two preparation rules map directly onto this list. Abstinence affects volume and total number. Transport time and temperature affect motility and vitality. That is why those two instructions are emphasized above everything else.

The lower reference limits published by WHO are widely misread, so it is worth being precise about what they are.

They are the fifth centile of results from men whose partners conceived within twelve months. In other words, five per cent of men with proven recent fertility fall below each limit.

What follows from that:

• A result just below a limit does not mean you cannot conceive — some men with proven fertility sit there
• A result above every limit does not confirm fertility, since the test measures the sample rather than the sperm's ability to fertilize
• The limits are not treatment thresholds, and no single parameter decides anything

The sixth edition explicitly repositioned these values as reference distributions rather than cut-offs separating fertile from infertile men. Results are meant to be read alongside your history, your partner's assessment, and how long you have been trying.

Laboratories reject or flag more samples than most people expect. The usual reasons are all preventable:

• Abstinence outside the 2 to 7 day window
• Incomplete collection, especially loss of the first fraction
• Delay beyond 60 minutes between collection and analysis
• The sample getting cold in transit
• Collection into a non-sterile or unsuitable container
• Use of an ordinary condom or lubricant

Beyond collection errors, a repeat is often requested simply because parameters vary. Two samples a few weeks apart give a far more reliable picture than one.

If your first result was abnormal, some questions worth asking before repeating:

• Was my abstinence period recorded, and was it inside the window?
• How long was the sample in transit?
• Was any of it lost during collection?
• Have I had a fever or illness in the last three months?

A surprising proportion of alarming first results resolve on a properly collected second sample.

The 2 to 7 day window has to fit around normal life, and a few situations make that harder than it sounds.

Situations worth planning around:

• Travel — a sample cannot be posted or carried for hours, so book the test for a period when you can attend in person
• Shift work — collection is usually needed during laboratory hours, and the sample must reach them within an hour
• Illness — if you have a fever, postpone. The result will be depressed and you will be repeating it anyway
• Recent vaccination with fever — the same applies, though routine vaccination without fever is not a reason to delay
• A partner cycle already underway, where the clinic may want the analysis by a particular date

If you are testing to investigate infertility rather than for treatment, there is no reason to rush a badly timed sample. A test collected under the wrong conditions produces a number that has to be discarded, which delays things more than waiting a week would have.

Book the appointment first, then count back to plan the abstinence window rather than the other way round. Two to seven days is wide enough that this is almost always achievable.

Results are usually described with a single word that combines the abnormal parameters. Knowing the vocabulary makes the report readable:

• Oligozoospermia — fewer sperm than the reference limit
• Asthenozoospermia — reduced motility
• Teratozoospermia — reduced proportion of normally shaped sperm
• Oligoasthenoteratozoospermia — all three together
• Azoospermia — no sperm found in the sample at all
• Cryptozoospermia — none seen initially, but sperm found after centrifugation
• Aspermia — no ejaculate produced

Some patterns point towards particular explanations:

• Low volume with low count — consider incomplete collection first, then partial retrograde ejaculation or ejaculatory duct obstruction
• Normal count with poor motility — consider heat exposure, varicocele, infection, or a transport and temperature problem with the sample
• Azoospermia — needs distinguishing between obstruction and a production problem, which requires hormone testing and specialist review
• All parameters low — often reflects a systemic factor such as recent illness, testosterone use, or heavy alcohol intake

Azoospermia on a first sample should never be treated as final. It requires confirmation on a second properly collected sample examined after centrifugation, because the finding carries serious implications and is occasionally a collection artefact.

What follows depends on the result and on your partner's assessment, which is usually happening in parallel.

If the result is normal:

• The male factor is unlikely to be the main obstacle, though the test does not confirm sperm function
• Attention moves to ovulation, tubal status and cycle timing
• No routine repeat is needed unless circumstances change

If the result is abnormal:

• A confirmatory second sample after a few weeks, using the same abstinence interval
• Referral to a urologist or andrologist if the second sample confirms it
• Physical examination for varicocele and testicular volume
• Hormone testing, typically FSH, LH and testosterone
• Scrotal ultrasound where indicated
• Genetic testing in severe oligospermia or azoospermia

Because the production cycle is about 74 days, any lifestyle change is assessed on a test roughly three months later. Repeating sooner tends to measure normal variation rather than the effect of the change.

• Fertility Myths vs Facts: Ten Claims Checked Against the Evidence
• IUI vs IVF — Which Treatment Is Right for You? (2026)
• Fertility Tests for Women: What Each One Checks, and When
• How Long to Abstain Before Fertility Testing
• Does Masturbation Lower Sperm Count? What the Evidence Says
• Hormonal Testing: What to Expect
• How to Prepare for a Fertility Test