How does estrogen stop bleeding in acute uterine bleeding?

No, tends to ↑ bleed: because it stimulates growth of underline lining. Conversely, progesterone, which triggers maturation of uterine lining, not growth, tens to stop bleeding. However both of slow onset to alter behavior because, like all steroids (derivatives of cholesterol) they alter transcription of genes within cell nuclei & there is typically a 12 to 24 hour delay before changes become apparent.