Having sex on ovulation day or just prior to ovulation day is the time that most doctors recommend for ensuring the highest chances of becoming pregnant. The most commons one are using an opk, a bbt thermometer and online ovulation tracking. If you time having unprotected sex during ovulation, your average chance of conceiving within three cycles ranges from 20 to 37 percent, the american society of reproductive medicine (asrm) states. The average chance of conception from having intercourse on the day of ovulation was about 33 percent in the nejm study cited above. i had sex on the day i ovulated and the two days before that (and i know i ovulated because i have this online ovulating chart that tells me when im fertile,ovulating and when my period is supposed to come). Well, i ovulated on july 3,2006, my period is supposed to come on july 17 but im already having bad cramps. I never get cramps till the day i get my period but these cramps come and go. Its been about a week and a day since then i havent experienced breast tenderness but my nipples are sensitive, i have a constant back ache, im nauseated, im emotional & i can feel something is different. If a woman has sex six or more days before she ovulates, the chance she will get pregnant is virtually zero. If she has sex five days before she ovulates, her probability of pregnancy is about 10 percent. Once you get a positive ovulation predictor test result, or otherwise think that you are ovulating, you can go ahead and have sex. If you are quite sure when you ovulate each month you can give yourself the best chance of getting pregnant by having sex in the days leading up to ovulation. I used the ovulation kits as well but we had sex every other day from the day my period ended until cd20. ovulation usually occurs between day 11 and day 21 of the menstrual cycle. Youve probably heard that ovulation occurs on day 14 of your cycle, but thats not necessarily true. so, if you have unprotected sex during the six-day window which includes five days prior to the ovulation day and the ovulation day, chances are you can get pregnant.