For Sperm, Quality Trumps Age in Fertility Treatment Outcomes

Fertility treatment outcome in terms of live birth is not affected by the age of the sperm donor, despite emerging evidence of a decline in sperm quality with increasing age, according to a study conducted in the United Kingdom.

These results reaffirm the observation that a couple's fertility appears significantly more dependent on the age of the female partner than on that of the male, said Meenakshi Choudhary, MD, PhD, the study’s principal investigator from Newcastle Fertility Centre at Life, Newcastle upon Tyne, United Kingdom.

Pertinent Points

- As expected, differences in live birth rate from IVF with donated sperm were found between women at peak reproductive age (18 to 34 years) and women older than 37 years (29% vs 14%, respectively).

- In the younger IVF patients, LBR was 28.3% with a sperm donor younger than 20 and 30.4% with a sperm donor aged 41-45.

- In the younger donor insemination patients, LBR was 9.7% with a donor younger than 20 and 12% with a donor aged 41-45.

These conclusions were based on an analysis of every first fertility treatment cycle (either IVF or donor insemination) performed between 1991 and 2012 in the UK using sperm donation registered by the Human Fertilisation & Embryology Authority (n=39,282). According to the researchers, this is the first study of the effect of sperm donor age on live birth using a large national database. The results of the study are reported this week at the Annual Meeting of European Society of Human Reproduction and Embrology in Munich by Dr Choudhary's colleague, Dr Navdeep Ghuman.

With the assumption that female fertility clearly declines with age, the study divided its female subjects into two groups: those who were treated with donor sperm between the ages of 18 and 34, and those who were treated after the age of 37. They were further subdivided according to treatment type-either donor insemination or IVF. The sperm donors were then divided into six age groups for the analysis (< 20, 21-25, 26-30, 31-35, 36-40, and 41-45).

As expected, results showed a difference according to female age in both treatment groups. The live birth rate from IVF with donated sperm was around 29% in the 18-34 age group, but only around 14% in the over-37 age group. However, within these same two female age bands, no significant differences were found in live birth rate (LBR) relative to the age of the sperm donor.

In the younger IVF patients, LBR was 28.3% with a sperm donor younger than 20 and 30.4% with a sperm donor aged 41-45. In the younger donor insemination patients, LBR was 9.7% with a donor younger than 20 and 12% with a donor aged 41-45.

Women aged 18 to 34 were considered to be at peak reproductive potential, whereas women older than 37 were thought to be less likely to conceive. Some differences were observed between these age groups, although none were of statistical significance. There was a trend, for example, that sperm donors younger than 20 had less successful outcomes than older donors. Thus, in the older IVF patients, LBR was 11% with a donor younger than 20, 17% with a donor aged 26-30, and 16.6% with a donor aged 41-45. Similarly, in the older donor insemination patients, LBR was 3.1% with a sperm donor younger than 20, and 4.6% with a donor aged 41-45.

Dr Choudhary suggests that the slightly lower rates of live birth from younger sperm donors “might simply be explained by the fact that younger men who donate sperm are less likely to have proven fertility themselves than older sperm donors with proven fertility."

However, these results from such a large cohort study show that the age of the sperm donor is of little significance in achieving a live birth. "It's sperm quality rather than male age that matters," Dr Choudhary said.

In the United States, the preferred age for sperm donors typically is younger than 40 years.

References:

Choudhary M et al. Age of the sperm donor: does it really matter - an analysis of 1,048,576 assisted reproduction treatment cycles. Paper presented at: 30th Annual Meeting of the European Society of Human Reproduction and Embrology. Munich, Germany. July 1, 2014. Abstract O-157.