Please be reassured that taking progesterone from the third to the seventh month of pregnancy is generally safe and highly unlikely to harm your baby. Progesterone is a natural hormone crucial for maintaining pregnancy. It is commonly prescribed during these specific months to prevent preterm labor or miscarriage in at-risk pregnancies. Extensive medical research shows that using progesterone during the second and third trimesters does not cause birth defects or harm the baby's development. It was likely prescribed to protect the pregnancy. I recommend discussing this with your obstetrician during your next prenatal visit for personalized reassurance.