It is possible to gain weight by taking progesterone, depending on individual circumstances and varies from person to person. Progesterone is a natural progesterone, if used blindly, it will have side effects on the body, such as nausea, dizziness, significant weight gain or loss, vaginal bleeding and swelling, etc. It must be used under the guidance of a doctor. Progesterone is mainly used for habitual miscarriage or pre-eclampsia caused by insufficient luteal secretion and progesterone deficiency. The application of progesterone in the early stage can lead to an increased chance of fetal malformation, so consult your doctor before using the medication. Frequent use of progesterone can also lead to decreased menstrual flow, vaginal inflammatory infections, endometrial atrophy, and, if synthetic progesterone is used, fetal masculinization.