Male fertility is becoming a bigger global health conversation

What happened?

In April 2023 the World Health Organization published its first major set of global infertility estimates in years, covering data from 1990 to 2021. Its headline figure was that about one in six people of reproductive age experience infertility at some point in their lives. The report stressed that infertility is common in every region of the world, in wealthier and poorer countries alike.

In the same year, the journal Human Reproduction Update published an analysis by Levine and colleagues that pooled studies of sperm counts collected across the 20th and 21st centuries. It reported a decline in average sperm concentration not only in North America, Europe and Australia, as earlier work had suggested, but also in South and Central America, Asia and Africa. The authors also suggested the decline may have become steeper after 2000.

Neither publication is brand new. They are discussed here because they continue to shape how doctors, health organisations and the media talk about male fertility.

Why are doctors talking about it?

For a long time, fertility care focused mainly on women. Yet infertility is a shared issue, and a male factor is often involved. The WHO figures gave the subject a clear, global scale, and the sperm count analysis added a sense that something may be changing at population level.

Together, they have strengthened the case for assessing men early, at the same time as their partners, rather than only after tests on the woman have come back normal. European urology guidelines already describe a structured assessment of the male partner, including history, examination and semen analysis.

What does it mean for men?

For most men, very little changes day to day. A population trend cannot tell you anything definite about your own fertility. What it does is make it more reasonable to raise the question sooner.

• If you and your partner have been trying for a while without success, both of you can be assessed. For men, this usually starts with a semen analysis carried out to standard laboratory methods.
• Some factors are worth knowing about, such as a history of undescended testes, previous testicular surgery or infection, or use of testosterone or anabolic steroids, which can suppress sperm production.
• General health matters. Doctors commonly discuss weight, smoking, alcohol and other health conditions as part of the assessment.

What we know

• Infertility is common worldwide, affecting roughly one in six people of reproductive age at some point, according to the WHO's 2023 estimates.
• Men are involved in a meaningful share of couples' fertility difficulties, and can be assessed with simple, standard tests.
• The Levine analysis found a downward trend in average sperm concentration in published studies from several regions.

What we still don't know

• Why sperm counts appear to be falling. Lifestyle, environmental exposures and other factors have been suggested, but the analysis was not designed to identify causes.
• How precise the trend is. The studies it combined used differing methods and populations over many decades, which makes comparisons harder.
• What it means for birth rates. Sperm concentration is one measure of fertility, not the whole picture, and many men with lower counts still father children.

Headlines about sperm counts can sound alarming. Our piece on how to read a health headline explains how to tell a population trend from a personal risk.

Questions men also ask

How is male fertility tested?

The usual starting point is a semen analysis, carried out in a laboratory using standard methods such as those in the WHO laboratory manual, alongside a medical history and examination.

Does a lower sperm count mean a man cannot have children?

Not necessarily. Fertility depends on several factors in both partners, and many men with results below reference values still father children, with or without treatment.

Sources & further reading

1. WHO Infertility prevalence estimates, 1990–2021 (opens in a new tab) (2023) World Health Organization
2. Human Reproduction Update Temporal trends in sperm count: a systematic review and meta-regression analysis of samples collected globally in the 20th and 21st centuries (opens in a new tab) (2023) Levine H, et al.
3. WHO WHO laboratory manual for the examination and processing of human semen, sixth edition (opens in a new tab) (2021) World Health Organization
4. EAU EAU Guidelines on Sexual and Reproductive Health (opens in a new tab) (2024) European Association of Urology

This article is general health information. It does not replace an individual medical consultation, examination or diagnosis. Read our editorial policy and medical review policy.