BERGEN, Norway, Feb. 16 (UPI) -- Men diagnosed with cancer before age 25 are much less likely to have children, and are less likely to get married than men without cancer, according to a large study of men in Norway.
The University of Bergen study found men who survived cancer early in life were less likely to reproduce or marry, and those who did reproduce were much more likely to seek fertilization assistance to have children.
Nearly 80 percent of those diagnosed with a range of cancers during childhood or adolescence will survive, a percentage researchers note increased significantly since the study started in the mid-1960s.
"It is important to be able to assure young, male cancer survivors that their illness and treatment will not have a negative impact on their own children," Maria Gunnes, a doctoral candidate at the University of Bergen, said in a press release.
For the study, published in the British Journal of Cancer, researchers analyzed medical records and data on the 626,495 men born in Norway between 1965 and 1985, as collected from national birth and health registries.
In the 20-year period, 2,687 men under age 25 were diagnosed with cancer, compared to 607,668 who were cancer-free. Of the survivors, less than half, or 1,087, had children, compared to 368,469 in the non-cancer group.
Of the cancer diagnoses, 30 percent were before age 14, 26 percent were between ages 15 and 19, and 43 percent were in young adulthood between ages 20 and 24. The most common forms of cancer diagnosed were testicular, central nervous system, lymphoma, and leukemia.
The researchers found that relatively few of the survivors, just 9 percent, were born between 1965 and 1979, with the majority diagnosed and benefiting from advances in cancer care after 1980. And while cancer survivors were found to be three times more likely to seek fertilization assistance, the researchers found no increased chance of prenatal death or congenital defect.
"These finds are important for male cancer survivors, seeing as we can identify groups at risk of having reproduction problems," Gunnes said.