This study will use thromboelastometry in ED patients with vaginal bleeding, as well as healthy pregnant controls, to determine if abnormal results are associated with the presence of vaginal bleeding as well as later complications during pregnancy.

First, a case control study with samples collected from patients in the ED and OB clinic at Mount Sinai Hospital will be performed. Blood samples are being collected at time of study entry. Patient health history will be collected and blood samples will be tested using thromboelastometry in prospective fashion. Samples will be compared between groups.

A prospective cohort will then be established using the subjects from the case control study. The purpose of this prospective cohort will be to collect outcomes of pregnancies to determine association with the initial thromboelastometry results.

Inclusion Criteria:

• Subjects will include pregnant women seen in the ED and OB clinic.

The ED patients will include those seen for vaginal bleeding during pregnancy at less than 20 weeks gestation.

OB Clinic patients will include those seen for first prenatal visit at which blood draw is performed, as long as this is also within 20 weeks estimated gestational age.

Exclusion Criteria:

• Patients with known histories of recurrent miscarriage, previously diagnosed thrombophilia, or other coagulopathy will be excluded.
• Patients with ectopic pregnancies will also be excluded.

Patients with known histories of recurrent miscarriage, previously diagnosed thrombophilia, or other coagulopathy will be excluded. Patients with ectopic pregnancies will also be excluded.