couple days ago, my girlfriend gave me a list of days that have the highest percentage rate for her to get pregnant. She did all the math stuff and figuring it out. The dates she got were: (May) 14, 15, 16, 17, (18), 19, 20 ,21, 22. May 18th is the day that has the highest chance of getting pregnant (if we do it without protection). Today, May 11, we did it without the use of protection. We did it for about 20 minutes and i took myself out of her before any sperm came out. But I heard that while doing it, some sperm leak out anyways. And also, I felt that orgasm feeling a bit before I took it out (but I'm not sure if any came out..usually it never did when I masterbated). Do you possibly think that the sperm came out? and plus, May 11 is way off the 14 - 22 list, and she said all the numbers off that list are 1-3 percent. How likely is it for fertilization?

Overall Questions:
1. Did the small orgasm tingle feeling mean that sperm came out?
2. If May 11th is the day that she can have 1-3 percent of being pregnant... how sure can we be?

The problem is that I don't know if any sperm came out inside of her when I felt that small orgasm tingle.

Your girlfriend can be a whiz at math - but she you two are pretty dumb about sex. That little feelling you got was the excitement phase of your ejaculation and most likely precum came out of your penis. Precum can make her pregnant.

Unless your girlfriend is absolutely regular - has been taking her temperature every day and checking how thick her vaginal lubrication is - she can not be so sure as to when she is fertile or not. The dates give in books/online are a guideline and are not absolutes. Teenagers expecially may be fertile for longer or shorter periods unless they have been menstruating for at least four years. It takes that long for a period to become really regular.

The chance she is pregnant are probably very slim, but if you do not want her pregnant than you two are taking stupid chances. You should never have your penis inside her unless she is on birth control and/ or you are using a condom. All it takes is one drop of your ejaculation to make her pregnant - and that can be the first drop that comes out of you.

Susan