A 29-year-old woman presents for heavy vaginal bleeding. She is hemodynamically stable. She had an uncomplicated vaginal delivery of a full-term baby 1 week ago. She denies fever or pain. There is active bleeding from the os. No cervical motion tenderness or signs of trauma or foul-smelling discharge. What is the most likely diagnosis? 

A. Uterine Atony

B. Retained products of conception

C. Cervical Trauma

D. Endometritis 

Answer: B is Retained products of conceptoin

-Given this occured 1-2 weeks after delivery, retained products of conception is most likely. 

-An ultrasound should be performed and OB/GYN should be consulted for possible D&C.

-Uterine atony is the most common cause of post-partum hemorrhage but this occurs immediately after delivery.