It is not possible to achieve 100% pregnancy on the day of ovulation, because pregnancy is a very complicated process for women, first of all there must be a combination of sperm and egg, the sperm needs the help of the man, if the man’s sperm is less active and has more dead sperm, then it is impossible for the woman to get pregnant. If the sperm and egg have combined, but still need to reach inside the uterine cavity in order to get pregnant, the process of reaching the uterine cavity from the fallopian tube, if the fallopian tube is blocked, in this case it is also impossible to conceive. If the sperm is mobile, but cannot reach the follicle and combine with the egg, pregnancy will not occur either.