Is it possible to be pregnant after 18 days of period?

Yes, it is possible to be pregnant 18 days after the start of your period, depending on your menstrual cycle. If you have a typical 28-day cycle, ovulation usually occurs around 14 days after the first day of your period, which is when you are most fertile. Sperm can survive in the female reproductive tract for up to five days, so if you had unprotected intercourse close to ovulation, there is a chance of pregnancy. If you suspect you might be pregnant, taking a pregnancy test or consulting a healthcare provider is advisable.