Brown discharge from IVF blastocyst transfer usually lasts for about 3-4 days, but there are individual variations. IVF is an in vitro fertilization embryo transfer technique, which is an assisted reproduction technique and has to be operated by a specialized doctor. Usually, the embryo will be implanted about 1 day after the blastocyst transfer, and luteal support therapy will continue to be given as prescribed by the doctor. At the time of blastocyst transfer, there may be a small amount of brown discharge, which usually lasts for about 3-4 days and then disappears on its own. However, the duration will be prolonged in case of symptoms of pre-eclampsia. A blood HCG (Human Chorionic Gonadotropin) test is usually performed at about 2 weeks after blastocyst transfer to confirm pregnancy, and an ultrasound can also be performed to check the development of the embryo. When the HCG doubling is not satisfactory, there may be a possibility of embryonic dysplasia, and there may also be brown vaginal discharge, which requires appropriate treatment as prescribed by the doctor.