hi , i m a male of 21 yr n i m having a loyalful relation with my partner , from a past year ago we r doing unprotected sex in starting she had taken ipill & as we started doing alternate days i had made her stop to take that , and we use to do unprotected sex & doing also , but ther is not a single thing come to listen about any problem or pregnancy . so we bth are worried about that . we knw a single sperm can make a lady pregnanat . so y it is not happening in our case. . pls help us with your answer