A semen analysis report can be full of numbers and worrying descriptions, especially when the percentage of normal forms is low. But the test isn't read as a series of pass-or-fail marks. It is a picture of several aspects of the sample, which are interpreted together and alongside the couple's history, and which can change from one test to the next.
What the test measures
The laboratory checks the volume of semen, the sperm concentration and total sperm count, their movement (motility), their shape (morphology) and, when needed, how many are alive (vitality). Concentration is the number per millilitre, while the total count also depends on the volume of the sample. Progressive motility describes sperm that swim forwards, which is different from sperm that simply move.
What the reference values mean
The lower reference limits in the World Health Organization's sixth edition laboratory manual include a concentration of about 16 million per millilitre, 30% progressive motility and 4% normal forms. These values come from the results of men whose partners became pregnant, and they are not a hard line separating fertility from infertility. Pregnancy can happen with lower results, and it can be delayed despite results within the reference range.
Does a low percentage of normal forms mean the baby will have abnormalities?
It shouldn't be read that way. Morphology is assessed against strict criteria for the sperm's head and other parts, and a large proportion of sperm can fall outside the ideal shape even in men who are able to father children. So a morphology result on its own doesn't mean the sperm will cause abnormalities in a child, and it doesn't decide treatment in isolation from the rest of the assessment.
How the sample is collected affects the result
Follow the laboratory's instructions on abstinence, usually between two and seven days, and use the container provided. Tell the laboratory if any of the sample was lost, especially the first part, and deliver it within the stated time. Also mention any recent fever, medicines or anabolic steroids, as these can help explain changes in the result.
When the test is repeated
If a result is abnormal, the test is usually repeated before conclusions are drawn, at a time that suits the situation. A severe shortage or complete absence of sperm needs a specialist consultation. Don't let a single number decide your chances: what matters is what the whole picture means and what the practical next step is.
This article is general health education and doesn't replace a consultation with your doctor.
