New Scientist: A father’s genes can increase the risk of a lengthy pregnancy by 30 per cent, new research shows. The discovery was made by Danish researchers analysing late births in pregnant women.

They found that women who had an unusually long first pregnancy, were less significantly less likely to have a second long pregnancy if the second baby had a different father.

This shows, says Annette Wind Olesen at the University of Aarhus, that a father’s genes partly determine the timing of his child’s birth. “It was very exciting to find out that there was a difference between fathers,” she says. “Knowledge about the birth mechanism is very sparse.”