Men have a variety of reasons for choosing to have a vasectomy, a surgical procedure in which the small tubes in the scrotum that carry sperm are cut or blocked off, so sperm can’t leave the body and cause pregnancy. For some men, it is a decision not to father any more children. For younger men, it may be motivated by a desire to assume responsibility for birth control.

With more men deciding to become fathers later in life, in some cases these older, hopeful dads-to-be have previously undergone a vasectomy. Vasectomies can be reversed, but until recently it has not been clear whether reversal could be equally effective at reestablishing fertility in older men.

No doctor wants to perform vasectomy reversals if it’s not appropriate for the patient.

The good news is a study from the University of Southern California’s Keck School of Medicine which found that partners of men over 50 who undergo a vasectomy reversal have about the same pregnancy rate as those of younger men who undergo a reversal. The rate of success for both is less than 50 percent, but not as different between age groups as had been expected.

Knowing pregnancy outcomes were the same for partners of older men and younger men who had vasectomy reversals gives couples and fertility providers more information to go on. “I think it’s good news for patients, because it gives them options,” Mary Samplaski, lead investigator of the study, told TheDoctor.

There is some decline in sperm quality as men age, she explained. Men's loss of fertility is not as dramatic as it is in women, but sperm count, sperm motility and ejaculate volume all begin to slowly decline once men are about 45 years old.

Almost 3,000 men younger than 50 years old and about 350 men 50 years old or older were included in the study. All the men had a vasectomy reversal at one of two healthcare facilities. All the procedures were performed by the same surgeon.

Factors such as when the man underwent the vasectomy, the age of his female partner and the man’s smoking status were taken into account. Among men younger than 50, about a third of couples achieved pregnancy after a vasectomy was reversed, as compared to 26 percent among men 50 years old or older who had had a vasectomy reversal.

The odds of achieving pregnancy were higher if the man had had a vasectomy less than 10 years earlier and/or if his partner was under 35. The odds were lower if the man smoked.

Going forward, Samplaski, an assistant professor of clinical urology at the Keck School of Medicine, and her colleagues would like to see if there is an age at which doctors should refuse to perform vasectomy reversals because it is unlikely to result in a pregnancy; or whether reversal may be an option no matter how old the man is, as long as he is reasonably healthy.

The study is published in Urology.