Some patients after embryo transfer, especially before the 12th week of pregnancy, are very nervous as they notice a coffee-colored vaginal discharge or a small amount of bleeding. Today we will learn about the causes and treatments. First, why will the flow of coffee or bleeding? 1, luteal insufficiency Progesterone secreted by the corpus luteum makes the endometrium metaplasia-like changes, which is an important contributor to the implantation of the fertilized egg and the development of the embryo. Therefore, if the corpus luteum function is insufficient in early pregnancy, and make the meconium poorly developed, it will affect the development of the embryo. Especially for patients after down regulation treatment, as the pituitary function has not been restored, luteinizing hormone (LH) production is suppressed, resulting in early luteal atrophy and insufficient function, and these patients are prone to post-transplantation abortion symptoms. This is why luteal support is routinely given in both fresh and resuscitation cycles. Luteal support drugs to progesterone (such as chenodeoxycholone, daflon, progesterone injection and other drugs), other drugs include small doses of HCG (after pregnancy will be ovarian corpus luteum into the corpus luteum of pregnancy, to maintain the production of sufficient amount of progesterone in early pregnancy), rLH, GnRHa. 2, uterine fluid IVF process of the uterine fluid mainly has the following three generation mechanisms: fertilized egg implantation of the accompanied by normal physiological state, Tubal pathology (such as tubal obstruction and effusion caused by salpingitis), and complex changes in the hormonal environment. The latter two pathologically generated uterine effusions are usually treated prior to implantation. The small amount of uterine fluid generated by physiological state is either absorbed by the organism or discharged, which is the manifestation of vaginal curry or dark red bleeding after transplantation. 3, embryo chromosome abnormality Some patients do the second ultrasound after the transfer of no fetal heart, or the sudden disappearance of the fetal heart after 8 weeks of pregnancy, suggesting that the empty gestational sac or embryo degeneration, fertilized egg chromosome abnormality is the most common reason for it. This kind of embryo will be eliminated naturally, the result of natural selection, do not have to force the birth control. Usually accompanied by bleeding and abdominal pain. It is important to understand that post-transfer abortion or a small amount of bleeding is not the same as having miscarried. The condition of the fetus should be judged directly according to the blood hCG level, progesterone measurement, ultrasound to check the morphology of the gestational sac and fetal heartbeat, so there is no need to worry about extra. Second, how to deal with? According to the above reasons, it is easy to see that the program that can be adjusted to preserve the fetus by adjusting the medication is mainly aimed at strengthening the luteal support. If the bleeding is small and there is no abdominal pain, it can be temporarily observed, keep a good attitude, bed rest, reduce activities, and usually can stop by itself. If the bleeding increases or persists, or is accompanied by abdominal pain, it is necessary to consult a doctor and follow medical advice.