What is the usual story with secondary infertility?  Secondary infertility happens to men who have conceived naturally, often easily, and who have a child already.  Confident that they will have another baby, they may wait for a couple of years before trying again and… it does not happen, so what is the story?

Clearly, everything was okay for them two or three years or so previously, but of course time has passed and something which was not significant then, now has become the problem.

For men, secondary infertility falls into two categories.  The first is a tendency to male subfertility which was always present, but which was compensated for by excellent or above average female fertility.  This is because the younger eggs were able to compensate for the less good-quality sperm.  This situation is typical of varicocele – a condition of harmless veins always present, but which warm the testicles and reduce the DNA quality of the sperm.  The sperm count may be reduced or can be normal, but the little packet of DNA in the sperm head is fragmented or slightly damaged, which affects both the creation of the embryo and the ability of those embryos to survive without miscarriage.  So this sort of secondary infertility can occur in any man who was a little subfertile, often with a low sperm count, when he was responsible for a naturally conceived live birth.  The reason for the subsequent secondary infertility is only because the passage of time has meant that his partner’s eggs have become older and are unable to compensate for the inadequacies of his sperm.

The other causes of secondary infertility relate to conditions or injuries which may have reduced fertility in a previously entirely and normally fertile man.  The most obvious cause is vasectomy, which prevents the sperm from leaving the testicles at all.  The same sort of obstruction can occur with infections which may block the tiny ducts which emerge from the testes in structures called the epididymides.  These infections are broadly known as epididymitis (that is, an inflammation of those tubules, often by organisms like a chlamydia).  Sometimes these genital infections involve the testicles, also known traditionally as orchids, and then this inflammation of the testicles is called an orchitis, in which the whole testicle is swollen and painful.  Orchitis can damage sperm production and therefore cause secondary infertility.  The sort of orchitis which might damage sperm production is associated with mumps, but not always.  Damage is more likely when the man is in young adulthood and when both testicles are swollen and painful.

Other causes of secondary damage to the testicles are relatively rare.  ‘Twisting’, or torsion, is uncommon in adults, but both the torsion which interrupts blood supply and the surgery to fix the testicle (an orchidopexy) can reduce fertility.

Other more generalised conditions can affect fertility, but these effects are usually transient in nature.  Sometimes, the treatment of these conditions compounds the effect of the condition.  Examples might be severe psoriasis and arthritis treated with methotrexate, and an inflammatory bowel disease treated with sulfasalazine.

Finally, in 2023, we have to mention COVID.  Evidence rather than data is very hard to get with the effects of any pandemic.  There are several reasons for this.  First, and most importantly, to change ‘observations’ (not scientific and open to bias) into evidence requires a prospective trial which cannot be randomised or controlled.  Therefore, scientists would have had to take known fertile men, look at a semen analysis, and even two analyses, then randomise them into two groups and regularly do further checks with COVID tests and sperm tests.  To prove that COVID positively caused a decrease in sperm numbers and quality would probably require a thousand willing subjects; such a study would take a great deal of medical time and money, and during a pandemic this was just not feasible, nor in fact was ever thought of.

The second built-in reason for the absence of evidence relates to the nature of COVID infections.  If fertility was affected, was it the direct effect of the virus or merely the effect of an illness with fever?

Finally, it may be that the different COVID mutations may have had different effects on fertility, so we are left with individual observations, which are otherwise known as clinical impressions, but my own conclusion is that COVID, particularly in the first and second waves, often affected both sperm count and sperm quality.  This conclusion is based purely on observations and we must say quite clearly that this is what I think, rather than what I know!

Therefore, secondary infertility and subfertility is important, but it does not necessarily mean that anything has substantially changed with the male other than the passage of time, but as you can see most cases are amenable at least to explanation and often to treatment.

To discuss your fertility please do contact us for an appointment.