Biggest effects seen for younger women with older men
MONDAY, July 10, 2017 (HealthDay News) -- A man's age makes a difference in whether or not a couple undergoing in vitro fertilization (IVF) ends up having a baby, a new study suggests.
The older the potential dad-to-be, the less likely the couple will have a live birth from IVF, the research showed.
For the study, the investigators examined nearly 19,000 IVF cycles performed with more than 7,700 couples in Massachusetts. The women were divided into four age groups: under 30; 30 to 35 years; 35 to 40 years; and 40 to 42 years.
As expected, the live birth rate was lowest in couples where the female was aged 40 to 42. In this group, the age of the male had no impact. However, when the woman was younger, the age of the man seemed to have a significant effect on childbirth success, according to the report.
For example, the live birth rate for couples with a female younger than 30 and a male aged 40 to 42 was 46 percent. In comparison, the live birth rate was 73 percent for couples with a woman younger than 30 and a man aged 30 to 35.
Also, couples with a female aged 35 to 40 had higher live birth rates if the male was younger rather than older, the study found.
The findings were presented recently at the annual meeting of the European Society of Human Reproduction and Embryology in Geneva, Switzerland.
"Our study found an independent effect of male age on the cumulative incidence of live birth," Dr. Laura Dodge, of Beth Israel Deaconess Medical Center and Harvard Medical School in Boston, said in a society news release.
"Generally, we saw no significant decline in cumulative live birth when women had a male partner the same age or younger. However, women aged 35 to 40 did significantly benefit from having a male partner who is under age 30," Dodge said.
"Where we see significant decreases in the cumulative incidence of live birth is among women with male partners in the older age bands. For women age 30 to 35, having a partner who is older than they are is associated with approximately 11 percent relative decreases in cumulative incidence of live birth -- from 70 percent to 64 percent -- when compared to having a male partner within their same age band," Dodge said.
Age-related DNA damage in sperm may affect fertilization, implantation or embryo development, she suggested.
Since the exact reason behind the lower live-birth success rate is unknown, Dodge said it's hard to offer couples advice. She said the best advice is to maintain healthy lifestyles before conception.
The study did not prove cause and effect between a man's age and in vitro fertilization success, just an association.
Research presented at meetings should be viewed as preliminary until published in a peer-reviewed journal.
The U.S. National Institute of Child Health and Human Development has more on assisted reproductive technology.