Prevalence of coagulation abnormalities associated with intrauterine fetal death

The purpose of this study was to determine factors associated with abnormal coagulation in the setting of intrauterine fetal death (IUFD).

We reviewed the charts of 238 patients diagnosed with IUFD over ten years. Data included demographics, co-existing obstetric disease and coagulation studies. A coagulation score was assigned based on the platelet count, prothrombin time, activated partial thromboplastin time and plasma fibrinogen concentration. Approximately 90% of the study population had coagulation scores < 4. A score of > or = 4 was considered abnormal.

Complete coagulation analysis was available in 183/238 patients (77%) within 24 hr of delivery. One hundred and sixty-four of these (89.6%) had a coagulation score, < 4 and 19 had a score > or = 4 (10.4%). No relationship between the coagulation score and age, parity, gestational age at delivery, and number of days the dead fetus remained in utero was found. A coagulation score > = or 4 was associated with the presence of a pregnancy-related disease (P < 0.05), notably abruption (P < 0.001) and uterine perforation (P < 0.05). Four patients without co-existing disease (3.2%), had a coagulation score > or = 4.

In most pregnancies complicated by fetal demise, the fetus and placenta are delivered within one week of fetal demise. The previously reported severe coagulation disturbances are largely eliminated by early delivery. Our study shows that coagulation abnormalities occur in some patients with uncomplicated IUFDs (3.2%) and that this number rises in the presence of abruption or uterine perforation.