London: Baby boys conceived through a common type of IVF treatment have lower sperm quantity and quality than men who were spontaneously conceived, suggests new research.
The findings are based on first results from the world's oldest group of young men conceived by means of intracytoplasmic sperm injection (ICSI) fertility treatment because of their fathers' infertility.
"These findings are not unexpected," said one of the co-authors of this study Andre Van Steirteghem, Emeritus Professor at Vrije Universiteit Brussel (VUB) in Brussels, Belgium.
"Before ICSI was carried out, prospective parents were informed that it may well be that their sons may have impaired sperm and semen like their fathers. For all the parents this information was not a reason to abstain from ICSI because, as they said: 'if this happens ICSI can then also be a solution for our sons'," Van Steirteghem noted.
"These first results from the oldest group of ICSI-conceived adults worldwide indicate that a degree of 'sub-fertility' has, indeed, been passed on to sons of fathers who underwent ICSI because of impaired semen characteristics," he added.
ICSI is a procedure by which sperm from the father is injected directly into the mother's egg in the laboratory, and then the fertilised egg is placed in her womb.
The technique was pioneered in 1990s at VUB's Centre for Reproductive Medicine headed by Van Steirteghem.
The first ICSI baby was born on 14 January 1992. The current study reports on 54 men, born in the early years of ICSI between 1992-1996, when ICSI was only used to treat male infertility.
The study, published in the journal Human Reproduction, found that these men, who were aged between 18 to 22, had almost half the sperm concentration and a two-fold lower total sperm count and total count of motile sperm (sperm that could swim well) than did naturally conceived men of a similar age.
In addition, compared to men born after spontaneous conception, the men born through the IVF technique were nearly three times more likely to have sperm concentrations below 15 million per millilitre of semen, which is the World Health Organisation's definition of "normal," and four times more likely to have total sperm counts below 39 million.
The study was carried out at University Hospital Brussels (UZBrussel) between March 2013 and April 2016. It is part of a larger project that is following the health of young adults, male and female, born as a result of ICSI.