Anticoagulants – drugs that stop blood from clotting – are widely used in medicine, including in some women of childbearing age. But while they can be useful and even life-saving, they can also be very risky during pregnancy, both for the mother and the baby.
Dr. Raymond O. Powrie, an obstetric internist and senior vice president for quality and clinical effectiveness at Women & Infants Hospital, and an associate professor at The Warren Alpert Medical School of Brown University, recently published an article in The Cleveland Clinic Journal of Medicine on this sensitive topic.
Powrie answered questions about the issues he addressed and the advice he offered.
PBN: What are the most common uses for anticoagulants in women of childbearing age?
POWRIE: Anticoagulants are most commonly used in pregnancy, to treat or prevent thromboembolic disease (TED) such as deep venous thrombosis and pulmonary embolism. TED is a leading cause of maternal death in the developed world, and so its treatment and prevention is essential. Anticoagulants are also used sometimes in women who have a clotting disorder that can be a cause of recurrent miscarriages.
For Leaders Who Don't Have Time to Get Sick
Top performers guard their calendars, delegate relentlessly and optimize every hour of the day. Health,…
Learn More
PBN: Is TED a problem specific to pregnancy?
POWRIE: TED is three to seven times more common in pregnancy and can be fatal if untreated .
PBN: Why are anticoagulants so dangerous in pregnancy?
POWRIE: The most commonly used anticoagulant used outside of pregnancy is the pill warfarin. We know that warfarin use in pregnancy can cause abnormalities in the fetus and so if possible, we try to avoid its use, especially in the first trimester. Fortunately, there is an injectable alternative, heparin, that comes in [two forms] that both appear to be completely safe for the baby, although like any anticoagulant, they do increase the mother’s risk of bleeding.
PBN: In general, anticoagulants are very carefully dosed and monitored, both in inpatient and outpatient care. When you do administer them to pregnant women, what extra precautions do you take?
POWRIE: We rarely use the heparins in non-pregnant patients for the long periods that we do in pregnant women, since we have the option of the pill warfarin. We do watch the patient for side effects such as bone loss, abnormalities in the blood counts and skin reactions as well as bleeding. Many physicians will do additional blood tests in pregnancy to make sure the dose that is being given is the right one, since we are not always sure that the dosing recommended for non-pregnant patient can be applied to the changing body of pregnant patients.
PBN: How familiar are most ob/gyns with these issues?
POWRIE: Obstetricians are very aware of the possibility of TED affecting their patients, and I think in our state very vigilant about watching for it. The message that warfarin is not safe in pregnancy, but that heparin, in its various formulations, is, is pretty well disseminated among physicians. Managing anticoagulation in pregnancy can be a little more tricky, and thankfully we have both an obstetric medicine team (internists trained in the care of medical illness in pregnancy) and maternal fetal medicine team (obstetricians trained in high-risk pregnancy care) at Women & Infants with broad experience in this management.
