You can’t get pregnant if you ejaculate on your underwear. Because sperm will not swim through the panties into the vagina and uterine cavity of a woman, it is impossible for them to combine with an egg to form a fertilized egg and cause a woman to become pregnant. Even if a woman puts on the semen-stained panties directly, it will not allow the sperm to enter the woman’s uterus, and the process of putting on the panties will only touch the outer tissues of the pubic area. In addition, usually after the male ejaculation, once the sperm leaves the vagina or prostate, the survival time outside the body becomes very short, usually not more than an hour or so, and with the time delay, the sperm vitality will become weaker and weaker, so generally the sperm simply stained on the panties will not lead to pregnancy.