A small amount of bleeding after pregnancy progesterone supplementation may be caused by insufficient drug dosage, poor embryo quality, gynecological diseases and other reasons. 1. Insufficient drug dosage: after pregnancy women due to progesterone insufficiency caused by aura miscarriage, to use progesterone under the guidance of the doctor to protect the fetus, if the dose of drugs used is not enough, there will be a small amount of bleeding after progesterone supplementation phenomenon. 2. Poor embryo quality: After pregnancy is caused by poor embryo quality miscarriage, such as chromosome number abnormalities, structural abnormalities, supplemental progesterone does not have much effect on the failure of birth control will still have a small amount of bleeding. 3. Gynecological diseases: after pregnancy, women themselves have vaginitis, cervicitis and other gynecological diseases, inflammation stimulation of the mucous membrane congestion, edema caused by bleeding, may be manifested in the pregnancy after supplemental progesterone there is a small amount of bleeding, this bleeding has nothing to do with the embryo itself. There are more reasons for a small amount of bleeding after pregnancy supplement progesterone, persistent bleeding is not clean to go to the hospital for a review, to further understand the reasons, do not self-medication, in order to avoid adverse effects.