Traditionally, women have been told not to delay childbearing too long due to their ticking biological clocks, with fertility significantly declining after the age of 32. The responsibility and stress of getting pregnant and having a child according to a particular timeline is typically solely on women, with men not having to face the same pressure.
But new research indicates some not-so-great news for men — their age, too, may affect a couple's chance of conceiving and having a healthy child. According to a new study from Harvard Medical School and Beth Israel Deaconess Medical Center, the older a man gets the incidence of live birth declines.
That's right, guys — the pressure to have a baby before one's biological clock runs out is no longer just on the women.
Researchers came to this conclusion by analyzing data from 7,753 couples going through in-vitro fertilization (IVF) between 2000 and 2014. The female partners were divided into four categories according to their age: under 30, 30-35, 35-40 and 40-42. Men were also divided into categories based on age, but they had a fifth group: 42 and over.
Researchers found that couples with women ages 40-42 had the lowest number of live births with the male partners' ages having no impact. What was particularly interesting, however, is that the number of live births for couples with women in all the other three age groups was impacted by the age of the male partner — that number significantly declined as the man’s age increased.
Specifically, in couples with the female under age 30 and the male between 40-42, the live birth rate was 46 percent, while women in the same age group partnered with men between the ages of 30-35 had a 73 percent birth rate. In other words, some women's chances of giving birth to a healthy child improved when they were with younger men.
While the reasons that women's fertility declines with age has been well-studied, it isn’t yet understood why male fertility does as well. “Declining sperm quality certainly plays some role, but our work shows that this is not the whole picture,” explains lead researcher Laura Dodge in The Guardian. “We found similar results among couples with no documented male infertility, so something else is happening.”
For example, older sperm is suspected to carry more DNA damage — which can affect live birth rates — and Dodge plans to investigate the causes for this and, hopefully, will uncover more answers in the future.
Obviously, a lot of men have children later in life: Clint Eastwood was 66 when he had his seventh child, Ronnie Wood was 68 when he welcomed twins, and Charlie Chaplin was 73 when his last child was born. But just because they succeeded in making babies later in life, doesn't mean every man will be able to.
Next time you think about pressuring a woman to have kids sooner rather than later, this study is a reminder that men, too, are fighting a similar reproductive battle against time.
What Do YOU Think?
Are you surprised by the findings of this study? Why do you think fertility decreases the older a man gets? Will this change your family planning tactics?