June 30, 2014
In Vitro Fertilization Birth Outcomes Unaffected By Sperm Donor Age
Brett Smith for redOrbit.com - Your Universe Online
Due to economic or other reasons, many women are putting off having children until their late 30s or 40s and some research has found this delay could mean an increased risk of pregnancy complications or the child having a developmental disorder.
The new study was based on a national database for over 39,000 in-vitro fertilization first treatment cycles conducted in the United Kingdom between 1991 and 2012.
"Whilst advancing female age is clearly associated with fertility decline, there is still no consensus about advancing paternal age and fertility outcome,” said Dr. Meenakshi Choudhary, a study author from the Newcastle Fertility Centre. “This is an area which is still much under-researched.”
“A few studies show an effect on DNA mutations which might explain a higher rate of miscarriage, pregnancy loss and birth defect,” Choudhary added. “Advanced paternal age has also been associated with long-term disorders in offspring. But the available evidence is limited.”
The researchers split female volunteers into two groupings: those who had been treated with donor sperm between 18 and 34, and those that were seen after age 37. These women were then divided up based on treatment method – a donor insemination or IVF. The sperm donors were then split into six age groups for the investigation: under 20 years old, 21 to 25, 26 to 30, 31 to 35, 36 to 40, and 41 to 45.
The researchers found a difference based on female age, for both treatment methods – with live birth rate from IVF with donated sperm around 29 percent in the 18-34 age group and 14 percent in the over-37 age group.
The more unexpected result was that there was no major difference in live birth rate for either age group with respect to the age of the donor. The live birth rate for women in the older group was slightly affected by donor age, but not enough to be called significant.
"Despite these trends," Choudhary said, "it's important to note that the impact of sperm donor age on live birth failed to reach statistical significance in any of the age groups we studied. Indeed, this trend of less likelihood of live birth with younger sperm donor age 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."
"It doesn't matter up to the age of 45 years, there was no decline observed in this study,” Choudhary told the BBC's James Gallagher.
The fertility doctor noted that the study results are specific to fertility treatments and should only be viewed in this context.
"I don't think you can take this data and apply it uncritically to the general population, the advice would still be you should be trying to have a child before the age of 40 or 45,” she said.