New York: Men who delay starting a family have a ticking "biological clock" - just like women - that may affect the health of their partners and children, according to the researchers.
Men who delay fatherhood should consult their doctor and consider banking sperm before age 35, said the study which reviewed 40 years of research on the effect of parental age on fertility, pregnancy and the health of children.
"While it is widely accepted that physiological changes that occur in women after 35 can affect conception, pregnancy and the health of the child, most men do not realize their advanced age can have a similar impact," said Gloria Bachmann, Director of the Women's Health Institute at Rutgers University's Robert Wood Johnson Medical School.
The study, published in the journal Maturitas, found that men aged 45 and older can experience decreased fertility and put their partners at risk for increased pregnancy complications such as gestational diabetes, preeclampsia and preterm birth.
Infants born to older fathers were found to be at higher risk of premature birth, late still birth, low birth weight, higher incidence of newborn seizures and birth defects such as congenital heart disease and cleft palate.
As they matured, these children were found to have an increased likelihood of childhood cancers, psychiatric and cognitive disorders, and autism.
Bachmann attributes most of these outcomes to a natural decline in testosterone that occurs with ageing, as well as sperm degradation and poorer semen quality.
"For example, just as people lose muscle strength, flexibility and endurance with age, in men, sperm also tends to lose 'fitness' over the life cycle," she said.
The study also found that older men struggled with fertility issues even if their partner was under 25.
"While women tend to be more aware and educated than men about their reproductive health, most men do not consult with physicians unless they have a medical or fertility issue," Bachmann said.
She recommended that physicians counsel older men as they do older women on the effect their age will have on conception, pregnancy and the health of their child.