THROMBOPHILIAS

A   26-year-old G4  P1  Ab2 woman   comes   in  for her first   prenatal    visit   at  8

weeks’  gestation   by  dates.  Her first   pregnancy   was a   spontaneous first-

trimester   loss,   for which   she underwent   a   D&C.    In  her second  pregnancy

she developed   right   lower   extremity   deep    venous  thrombosis  at  29  weeks,

which   was followed    by  an  unexplained fetal   demise  at  30  weeks.  Labor   was

induced with    PGE2.   The fetus   was normal  in  appearance, without

congenital  anomalies.  Autopsy on  the fetus   was unremarkable.   Her last

pregnancy   was also    a   spontaneous first-trimester loss.   Her sister  has a

history of  recurrent   deep    venous  thrombosis.

The thrombophilias are disorders which promote blood clotting due to an excess
of clotting factors or a deficiency of anticlotting proteins that limit clot
formation. Prevalence is as high as 20% of the population, but most individuals
are asymptomatic. Some will develop deep vein thrombosis or venous
thromboembolism (VTE) that can become life-threatening.

Risk factors include immobilization, surgery, or pregnancy. Pregnant women
with a thrombophilia are also at higher risk than other pregnant women of
developing a VTE.

Pulmonary embolus is the leading cause of maternal death in the United States;

50% of pregnant women who develop a pulmonary embolus or other VTE have
an underlying thrombophilia.