Yes, it is possible to get pregnant after having your menstrual period and then having sex. While the likelihood of becoming pregnant is generally lower during menstruation, it is still possible under certain circumstances.

The menstrual cycle consists of several phases, including menstruation, the follicular phase, ovulation, and the luteal phase. During menstruation, the uterus sheds its lining along with unfertilized eggs, and it is less likely for a woman to conceive during this time. However, sperm can survive in the reproductive tract for up to five days, so if you have sex towards the end of your period and ovulate shortly after, it is possible for the sperm to fertilize an egg and result in pregnancy.

Furthermore, the timing of ovulation can vary from woman to woman and can sometimes occur earlier or later in the menstrual cycle. Therefore, if you have a shorter menstrual cycle or experience irregular cycles, the chances of becoming pregnant shortly after your period may be higher.

If you are trying to avoid pregnancy, it is important to use appropriate contraception consistently and correctly, regardless of where you are in your menstrual cycle. If you are concerned about pregnancy or have specific questions about your menstrual cycle, it is always best to consult with a healthcare professional for personalized advice.