I'm spotting and my periods stopped last week Tuesday and on Wednesday I had sexual intercourse now I am spotting what might be the cause?

Irregular periods. Irregular periods are one of the most common problems Obgyns treat. If this is one time problem it usually resolves on its own. If this is a recurring problem you should be evaluated. Infections & hormonal changes can cause spotting. If there is a concern for pregnancy then do a home pregnancy test . There are many options available to help regulate the menstrual cycle. Schedule a visit.
Few causes. Could be due to trauma, small polyp, cervical lesion, fibroid, contraception, and so forth If you think there is something not right there, get it checked by your doctor to find the cause and act accordingly.

Related Questions

Had my period last month, but a week after my period I was spotting, had sexual intercourse. Now my period is late. What is happening?

Check pregnancy test. Because you're late, check HPT. Irregular menses are very common in young women. Check out http://en.Wikipedia.Org/wiki/anovulatory_cycle for info re anovulatory cycle as cause of irregular menses. Hormonal birth control pills can be used to regulate menses but don't prevent sexually transmitted diseases. You'll need to make your partners wear condoms each & every time to lower infection risk. Read more...