<s>[INST] my gf has regular period on 20 to 26 but we had sex on 21st of august...and next day i gave her unwanted 72....so she got her period on 28 to 2 September...and in the next month now it s 6 oct sgedidn t get her next cycle what could be the reason???help me out [/INST] Hello, and I hope I can help you todayUnwanted 72, when taken correctly, reduces a woman's chance of pregnancy from an unprotected encounter to less than 10%. However, unfortunately that means that one in 10 women still can conceive even if they take the medication correctly. Furthermore in the cycle that she takes it the medication can delay or affect her cycle.So just to be safe, I would recommend that your girlfriend do a urine pregnancy test. It does not need to be done in the doctor's office you can purchase one over-the-counter. However, she did have a normal menstrual cycle since she took the unwanted, which is a good sign that she is not pregnant.Women can have irregular menstrual cycles from hormonal changes due to stress, weight or schedule changes, and other medical hormonal problems.If her pregnancy test is negative, and your girlfriend is not menstruate for three months, she should see a GYN doctor for an evaluation to figure out why.I hope I was able to adequately answer your question today, and that my advice was helpful.Best wishes, Dr. Brown </s>