Ovulation happens when one of your ovaries releases a mature egg (ovum) that will await fertilisation. The egg is then available for fertilisation. The fertilisable lifespan of an ovum is approximately 24 hours. The fertilisable lifespan of a sperm is 48 hours. The most fertile days in the menstrual cycle are 12 to 16 days before the start of the next period. Try out this handy ovulation calculator.
(Ilse Pauw, Health24)