Usually it is women wanting to get pregnant who watch their diet and lifestyle and even go in search of unproven alternative therapies to increase their fertility.
But studies of a new supplement for men suggest he should play his part if he wants to become a dad.
Menevit, which has shown to increase pregnancy rates among IVF couples, is now available over the counter to any man concerned about his sperm count.
Fertility doctor Mary Birdsall explains how and why it works. Watch the video.