Brief Answer: I will try to help Detailed Answer: The first day of bleeding is day 1 of the menstrual cycle. Once you ovulate, the first day of the next cycle is twelve to fourteen days away. In other words it's the fist part of the cycle ( to ovulate) that varies, not the last part. You are most fertile right around that 2 day ovulation window. If your cycle varies from 19 to 25 days then you are ovulating anywhere from day 5 through 13 [(19-12 to 14 days= days 5 to7) and days (25- 12-14 days= days 9-13)]. sperm can live up to 3 days. So you should be intimate at least every other day beginning day 3-9 of your cycles. I added a few days either side of your range to not miss an opportunity. if your longest cycle is more than 25 days then extend this interval. There are commercial kits that test urine to pinpoint ovulation, and a very precise thermometer can be used called a basal body thermometer. Taking your temp everyday before activity, even going to the WC, a half degree rise occurs after ovulation. This confirms when you ovulate but you'll miss a few days of fertility just before. I hope this helps. I wish you an easy pregnancy and good health.

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