Understanding Your Semen Analysis Report

For most men, a semen analysis is the first and only window into their fertility. It is also, too often, handed over without a word of explanation: a grid of abbreviations, decimals and percentages, and a waiting room full of anxiety. This guide walks through the report line by line so that nothing on the page is a mystery.

What the test actually measures

A semen analysis assesses a fresh ejaculated sample under a microscope, usually after two to five days of abstinence. It describes four things: how much semen there is, how many sperm it contains, how well those sperm move, and what proportion are normally shaped. It also checks the chemistry of the seminal fluid.

What it does not measure is the genetic quality inside each sperm. Sperm can look and swim normally while carrying fragmented DNA, which is why separate tests exist for that. Understanding this limitation early saves a lot of false reassurance.

Volume and appearance

Volume is the total amount of semen produced, measured in millilitres. The WHO 2021 lower reference limit is 1.4 mL. A consistently low volume can point to a blockage, retrograde ejaculation, incomplete collection, or a problem with the seminal vesicles and prostate, which produce most of the fluid.

Your report may also note appearance, liquefaction time and viscosity. Semen normally liquefies within 15 to 30 minutes; if it stays thick, sperm can struggle to move freely.

Concentration and total count

These two are frequently confused. Concentration is the number of sperm per millilitre; the lower reference limit is 16 million per millilitre. Total sperm count multiplies concentration by volume to give the number in the whole ejaculate; the limit is 39 million.

The distinction matters. A man with excellent concentration but very low volume can still have a low total count, and vice versa. Below either threshold the report may use the term oligozoospermia. If no sperm are found at all, that is azoospermia, which always warrants specialist assessment.

Reference limits describe the lowest five per cent of men who fathered a child within a year. They are a signal to look closer, not a verdict.

Motility

Motility is reported in two ways. Total motility is the share of sperm showing any movement at all, with a lower limit of 42%. Progressive motility is the share swimming actively forward, with a lower limit of 30%. Progressive motility is the more meaningful figure for natural conception, because only forward-swimming sperm complete the journey to the egg. A result below these limits may be labelled asthenozoospermia.

Morphology

Morphology is the percentage of sperm with a normal head, midpiece and tail, assessed under strict criteria. The lower reference limit is just 4%, which surprises almost everyone who reads it for the first time. Even men who conceive easily typically have a large majority of imperfectly shaped sperm. Below 4% the term is teratozoospermia, but in isolation a low morphology figure is rarely the whole story.

Vitality and pH

Vitality measures the proportion of sperm that are alive, with a lower limit of 54%. It is particularly useful when motility is very low: it separates sperm that are alive but sluggish from sperm that are simply dead. pH should be 7.2 or above; an acidic sample can indicate a blockage or infection of the accessory glands.

You can read the reference table to understand the upper and lower limit of each parameters or you can enter your own concentration, motility and morphology into our semen parameter check to see each value flagged against these limits.

What a low result actually means

This is the part most reports leave out. The WHO limits are derived from the fifth centile of a reference population of roughly 3,500 men whose partners conceived within twelve months. By definition, five per cent of proven-fertile men fall below each limit. The sixth edition of the manual explicitly warns against treating the fifth centile as a hard threshold separating fertile from infertile men.

Sperm parameters also fluctuate substantially with illness, fever, abstinence period, stress and heat exposure. For that reason a below-range finding is normally confirmed with a repeat analysis, typically two to three months later, which is roughly one full sperm production cycle.

If a repeat test confirms a low value, the next steps usually involve a physical examination looking for a varicocele, a check for infection, and sometimes a hormone panel. Those are conversations for a clinician, and this article is designed to help you walk into that conversation already knowing what your numbers mean.