50% will have a benign cause, the other 50% will have a life threatening cause
Life Threatening Causes:
Placenta Abruption
Placenta Previa
Uterine Rupture
Vasa Previa (fetal vessels crossing or running in close proximity to the inner cervical os.
Benign or Non-OB Causes
Contact Bleeding (local trauma)
Cervical Inflammation (i.e. infection)
Cervical effacement and dilation
Cervical cancer
Other sites:
rectal bleeding
urinary bleeding
Evaluation:
ABC's: Stablilize mother, consider 2 large bore IVs
Consult OB/GYN early (most centers with OB/Gyn will have these patients evaluate and treated in Labor and Delivery), if not readily available complete evaluation as listed below:
Initially avoid bimanual exam
Obtain baseline labs (CBC, Coags, Chemistries, Consider LFTs if suspecting eclampsia or HELLP syndromes). If not known obtain Rh status
Fetal Monitioring ideally with continous fetal heart rate and tocometry
Sterile Speculum exam for culture and check for active bleeding.