<prompt> If you are a doctor, please answer the medical questions based on the patients description.hi doctors out there I want to know if you been trying to get pregnant for 9yrs and didn t and you been taking birth control pills then stop then you start taking prenatal vitamins 3 months after taking birth control pills then stop taking those to and then have unprotected sex wit your man 2 days after stop taking prenatal pills and 3 days later you see a dark brown spot in your panites way after you had cramps wat does this means because I have doubts im pregnant because ive been trying for a long time but got no luck so can you tell me wat this means please im concern  <response>: Hi, Prenatal vitamin pills usually wont affect menstrual cycle. After stopping the birth control pills it will take some time for regularization of hormonal levels. The possible causes for spotting are:-Hormonal imbalance leading to menstrual irregularity. -Sometimes in early pregnancy spotting can be seen. -Local causes like cervical erosion, polyps etc. So, once consult gynecologist, get examined and go for ultrasound. If she recommends go for investigations like thyroid profile, hormonal profile including estrogen, progesterone, LH, FSH etc. Possibly with this workup the cause for your problem can be identified and treated. Take care. 