The 11 weeks plus 4 days of pregnancy underpants a little brown secretion, do ultrasound did not see obvious abnormalities may be a precursor to miscarriage, inflammation and infection and other reasons. 1. Miscarriage precursor: women in early pregnancy brown discharge, do not rule out the aura of miscarriage, at this time to see the development of the gestational sac, if the embryo development is normal, ultrasound examination of the uterus embryonic tissues and fetal heartbeat, it is recommended to bed rest during pregnancy, avoid lifting heavy objects and strenuous exercise, so as not to cause miscarriage, can be in the guidance of the doctor to play progesterone or eat progesterone tablets to protect the fetus treatment. 2. Inflammatory infections: If pregnant women have inflammatory infections, brown discharge may also occur, such as mycosis vaginalis and other gynecological diseases, so pregnant women should pay attention to the hygiene of the private parts, wash their private parts with lukewarm water every day, maintain a happy mood, and appropriate exercise. If the ultrasound does not see obvious abnormalities, there is no need to worry too much, but if accompanied by other uncomfortable symptoms or other abnormal results, it is recommended to seek medical attention in a timely manner, under the guidance of the doctor to carry out professional treatment, do not blindly use their own medication or delayed treatment, so as not to cause adverse consequences.