Case: 32-year-old newly pregnant patient admitted to the ICU with Pulmonary Embolism, and now getting discharged. The clinician decided to keep her on unfractionated heparin with a dose of 5000 units every 12 hours. As the pregnancy progresses, the dose of unfractionated heparin should be increased proportionally.
A) True
B) False
Answer: A
The unfractionated heparin dose should be increased as pregnancy progresses, as Heparin prescription is weight-based. A general rule of thumb is every 12 hours dose of:
- 5000 to 7500 units in the first trimester
- 7500 to 10,000 units in the second trimester
- 10,000 units in the third trimester
That said, clinical judgment and close monitoring of bleeding risks are required.
#ob-gyn
#hematology
References:
1. American College of Obstetricians and Gynecologists' Committee on Practice Bulletins—Obstetrics. ACOG Practice Bulletin No. 196: Thromboembolism in Pregnancy. Obstet Gynecol 2018; 132:e1. Reaffirmed 2022.
2. Barbour LA. Current concepts of anticoagulant therapy in pregnancy. Obstet Gynecol Clin North Am 1997; 24:499.
3. Mok T, Nguyen AV, Kwan L, et al. Prophylactic Unfractionated Heparin in Antepartum Hospitalizations: A Randomized Controlled Trial. Obstet Gynecol 2024; 144:118.

