Can low progesterone levels cause a mmc that requires d&c because my body wouldn't naturally miscarry? i was 11 1/2 weeks, baby was 8 1/2.

Unlikely this case: Very sorry for your loss. Low progesterone levels are sometimes linked to pregnancy losses, but in most women it's a non-isuue. Most all 1st trimester losses (98-99%) are due to genetic causes in the embryo/fetus. A case like yours where the baby is much smaller than gestational age is 99.9% not due to a progesterone problems. Good wishes, hope this helps.