What birth control pill would make you have a period?

Answer 1

You are probably referring the PLAN B, which is often called the Emergency Pill or Oral Contractive Pill. This is taken when unprotected sex takes place and the fear of pregnancy exists.

Plan B are two hormone pills which will trigger a menstrual cycle. You are basically forcing the body to menstruate and therefore prevent pregnancy from occuring.

If you are already pregnant, however, PLAN B pills will be ineffective.