The transplantation here is the test tube transplantation, the test tube transplantation 20 days flow brown discharge small abdominal pain, may be aura miscarriage, fetal arrest, ectopic pregnancy, gynecological diseases and other causes. 1. Miscarriage with aura: the lack of progesterone in a woman’s body after in vitro fertilization may cause miscarriage with aura, which stimulates the uterus to contract with brown discharge accompanied by abdominal cramps. 2. Fetal arrest: 20 days after the IVF transplantation of brown discharge small abdominal pain may be fetal arrest, the embryo due to chromosomal abnormalities, maternal viral infections and other factors leading to fetal arrest, and not be able to normal pregnancy in the uterus, spontaneous detachment from the uterine wall, the beginning of the symptoms of brown discharge small abdominal pain. 3. Ectopic pregnancy: after in vitro fertilization, the embryo does not normally settle in the uterine cavity, but settles in places other than the uterine cavity, such as the fallopian tube, with the gradual development of the embryo, may stimulate the fallopian tube to swell and rupture, and initially show the symptoms of brown discharge and abdominal cramps. 4. Gynecological diseases: women themselves have gynecological diseases, such as pelvic inflammatory disease, stimulated by inflammation, there may be brown discharge small abdominal pain symptoms. There are many reasons for brown discharge and abdominal pain after 20 days of IVF transplantation, and it is recommended to seek medical treatment in time for serious cases.