Ovulation’ is the process of an egg being released from an ovary and this happens 12-16 days before her next period starts. ‘Fertile days’ are the days during a woman’s menstrual cycle, leading up to and including the day of ovulation, when she has the ability to become pregnant if she has unprotected sex.
There are many ovulation calculators available today that estimate when your fertile days will occur. These calculators are a form of ‘calendar method’ and work on average data without reading anything about your personal hormone levels. However, none of us are ‘average’:
1. Cycle lengths vary from woman to woman and cycle to cycle – in fact nearly 50% of menstrual cycles vary by 7 or more days1
2. The timing of ovulation can vary by a few days, even in regular cycles.