The male factor represents 35% of primary infertility cases
When we talk about primary infertility we are referring to couples who have not been able to conceive after a year of having sexual intercourse without using birth control methods. This period of time, in fact, is shorter for women over 37 years of age ( six months)
In this regard, the male factor represents 35% of the causes of primary infertility.
In addition to the above, we can say that male factor infertility also contributes to 30% of mixed‑cause cases. This refers to cases in which male and female‑factor infertility are associated with one another. Finally, the remaining 35% of primary infertility cases are due to female infertility factors.
These percentages are the findings of a study we carried out at the Centro Gutenberg Reproduction Unit by analysing data from 2014 to the present.
Study on male factor infertility
The study we carried out at URE analysed the clinical results obtained using the in vitro fertilisation with sperm microinjection (ICSI) technique. This technique was used in couples with male factor infertility and in couples with mixed‑cause infertility, in women under the age of 40. We came to the conclusion that couples have a very good prognosis when the male factor is the sole cause of their infertility.
In this regard, we were able to achieve a pregnancy for 7.6 out of every 10 couples who underwent ICSI treatment due to male factor infertility. In cases where the female also contributed to the couple’s infertility, the success rate with ICSI decreased, though it remained favourable: 5.5 out of every 10 couples achieved a pregnancy.
Decline in sperm quality
It is estimated that 75% of males who go to assisted reproduction clinics will have an abnormal sperm analysis. This percentage clearly differs from the numbers we observed twenty years ago, so much so that the World Health Organization needed to set new fertility parameters in terms of establishing assessment criteria.
The decline in sperm quality in 40% of the cases of unexplained infertility could be attributed to lifestyle and environmental factors.
The deterioration of sperm quality, together with the delay in the age at which women begin trying to conceive their first child, are the main causes of the alarming increase in infertility rates. The age of the male, until very recently, was not taken into account, but it seems as though it can also have a negative impact on conception. Pregnancy rates specifically start to decrease after a male turns 45.
Male infertility at Spain
According to data from the National Statistics Institute, Spain has one of the world’s lowest birth rates (1.3 children per woman), females who become first‑time mothers, on average, at 32.1 years of age (later than the average age worldwide), and is a country where practically 11% of child are born to women over the age of 40.
At present, it is estimated that one in every five couples will require assisted reproduction in order to have children. In spite of the fact that it has always been believed that females were the main reason for a couple’s infertility, data published over the last few decades has shown that the male factor has also been having an increasing impact on fertility issues as well.