This pilot study will assess the performance of the Quantra System with the QStat Cartridge versus standard of care coagulation testing in bleeding pregnant women at delivery.

The Quantra System is a fully integrated and automated in vitro diagnostic device which uses SEER Sonorheometry, an ultrasound-based technology, to characterize the viscoelastic properties of a whole blood sample during coagulation. The QStat Cartridge was developed to monitor hemostasis in patients that may experience a range of coagulopathies of various etiologies including fibrinolytic defects. These patients include the tobstetric hemorrhage population. The cartridge consists of four independent channels each containing different sets of reagents, which provide four measurements performed in parallel yielding five parameters that depict the functional status of a patient's coagulation system.

This single-center, prospective, observational pilot study will evaluate the performance of the Quantra System with the QStat Cartridge as compared to standard of care coagulation testing in bleeding pregnant women at delivery.

Inclusion Criteria:

• Subject is > 18 years.
• Subject is pregnant or at least 24 h postpartum
• Subject is fluent in English language.
• Subject is experiencing significant bleeding resulting in activation of the stage 2 OB hemorrhage protocol as defined by blood loss ≥1500ml at delivery or within the first 24 hours after delivery, and/or is hemodynamically unstable and/or is experiencing increased abnormal bleeding not responsive to OB stage 1 hemorrhage resuscitation.
• Subject or subject's legally authorized representative (LAR) is willing to provide informed consent, either prospectively or by deferred consent.

Exclusion Criteria:

• Subject is incarcerated at the time of the study.
• Subject is currently enrolled in a distinct study that might confound the results of the proposed study
• Subject is affected by a condition that, in the opinion of the clinical team, may pose additional risks

Pregnant females

Pparturients 18 years or older who experience an obstetric hemorrhage around the time of delivery or cumulatively over 24h after delivery or unstable vital signs or clinical signs of a coagulopathy managed with activation of the stage 2 OB hemorrhage protocol.