Hello, Your wife is sexually active and you had sex with her on the day she was done with her periods. You had unprotected sex but she took emergency CP within 36 hours. Presently, she is not having periods and the pregnancy test is negative. You are suggested to let her wait for a couple of days and if she does not get periods, she should repeat pregnancy test with the first morning, mid stream urine. If the test is positive she will be managed accordingly and if she is not pregnant, she will be asked by her treating doctor to get few more tests to detect any hormonal problems, thyroid dysfunction, anemia, PCOS, stress, etc. The pathology causing the symptom will be treated accordingly. Sometimes, due to the side effects of the emergency CP taken your wife may experience delay in menses, scanty periods, irregular periods or at times even heavy periods. In the meantime, you are suggested to stay away from addictions if any & take home made, balanced, nutritious food. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician