It depends on the person. Sometimes fertility lasts for just a few hours and sometimes it lasts for three days or even longer. The ovulation kit can help you monitor your fertile days.
There are five days of the menstral cycle in which you can become pregnant, determining when these days occur can only be done via taking your core temperature every morning before getting out of bed and charting.
Each person differs slightly in their days in which they are fertile. The time ranges anywhere from three to five days, but it may be different for some people. It is a little difficult to figure out exactly when you are most fertile.
