<prompt> Answer this question truthfullyWhat are the main causes of post-partum hemorrhage and how can they be remembered using the 4 Ts?  <response>: <reason> The main causes of post-partum hemorrhage are uterine atony most common, trauma lacerations, incisions, uterine rupture, thrombin coagulopathy, and tissue retained products of conception. These can be remembered using the 4 Ts. 