The first day after menstruation is usually not pregnant, but there is still a possibility of pregnancy, only the chances of pregnancy are smaller.
In general, women with regular menstrual cycles, the average cycle is 28 days, about 14 days before the next menstrual period is the day of ovulation, sex at this time, the probability of pregnancy will be greater, but the day of ovulation is not set in stone, because ovulation will be affected by mood, weather, nutrition and other factors, if a woman’s cycle is already irregular, the day of ovulation is even more impossible to deduce.
It is not recommended to have sex immediately after the first day of menstruation because it will increase the possibility of infection of the female reproductive system. It is recommended to consider having sex 3 days after the end of menstruation, and if there is no plan to get pregnant, it is important to take good contraceptive measures, and you can’t rely on the projection of the day of ovulation to determine whether there is a possibility of pregnancy.