When am I most fertile. Last month 1st of my period was on the 24 feb 2015. When should I have sex to conceive?

March 7-13. You are most fertile around the time of ovulation. Most women ovulate about 14 days before their next period. You can test for ovulation using an ovulation prediction test available at good pharmacies without a prescription. If your period started Feb 24, the best time to "try" is between March 7 and 13. Best wishes!