How does low progestrone cause miscarriage (in brief)? how far along in pregnancy does this kind of mc usually happen? pls no website links.thank you

Progesterone: Low progesterone, also referred to a luteal phase defect is most likely to produce a first trimester miscarriage. Most often 5 1/2-8 weeks, though your LMP based gestational age may say you're further along when it is discovered as it may take a week or two to get symptoms. The placenta takes over progesterone production around 12 weeks, which is why this is a first trimester issue