Have sperm counts declined? Is male factor infertility on the rise? What you need to
This is a red hot topic today especially after a recent report by Hagai Levine et al in
Human Reproduction that showed sperm counts significantly declined from 1973-2011
with a 1.4% drop per year and an overall decline of 52.4% over that time period. On the
surface, this is truly remarkable and scary. But is male factor infertility really on the rise
and are these findings valid?
First, all infertility experts recognize that a male factor may exist in about 40% of couples
that have infertility. So, regardless of the findings of the above study, male factor
infertility is very common. This study, while very interesting, has many limitations.
Levines’ study was a meta analysis of previously published studies and that lends itself to
bias and error. In addition, the Levine study used 2010 WHO standards defining an
abnormal sperm count as less than 40 million sperm per ml. The current WHO standard
defines an abnormal count as less than 15 million per ml. In fact, the WHO has
continually decreased the minimum normal threshold from 80 million to the current
standard of 15 million per ml. This suggests that the previous standards were too strict,
mislabeling many men as abnormal who are, in fact, not infertile. The 40 million WHO
standard used by the Levine study is not used today.
Infertility experts recognize that a male factor may exist in about 40% of couples
that have infertility.
In my experience, the current WHO standards are very helpful and reliable when
evaluating male factor infertility. The current normal standards are: Count >14 million
per ml, motility >39% per ml and morphology >3% with a volume of 1.5-5 ml. Many
experts including myself believe that motility and especially morphology are the more
important parameters. Obviously, if the sperm is not moving then the count becomes
irrelevant. Morphology defines the shape of the sperm and if the sperm are not properly
shaped then they are not able to penetrate the egg, again causing infertility.
What’s new and most interesting is a new test for male factor infertility called “seed” that
is now clinically available from a company called Episona. It’s very different from the
traditional semen analysis in that it tests for “epigenetic” factors that can impair DNA
gene expression. Epigenetic markers affect the way our genes are read by the cell. This
test can identify the number of abnormal epigenetic sites on the sperm. These sites can
be influenced by factors such as chronic stress, diet, alcohol abuse, smoking and other
environmental factors. So, this test allows one to potentially improve sperm function by
altering ones’ life style. Although “Seed” is a new test, it may have value in further
evaluating, diagnosing and treating male factor infertility especially in those couples with
unexplained infertility or those who have failed IVF with poor fertilization rates or
embryo development. Dominion Fertility offers this new test for our patients.
In summary, male factor infertility is most common and sometimes difficult to diagnose.
I find the current WHO standards to be valid and I believe the “Seed” test is a interesting
genetic test that may further add to our ability to diagnose and manage male factor
infertility. Stay tuned as more exciting and clinically worthwhile tests become available
in the area of male factor infertility.
Michael DiMattina, M.D. Medical Director,
Dominion Fertility, Arlington Virginia.