Safety and use of autologous blood donation during the third trimester of pregnancy.

To examine autologous blood donation during the third trimester of pregnancy, records of 272 blood donors who donated by standard procedures were reviewed. The incidence of vasovagal reactions at autologous donation was 2.1% (7/341) versus 1.1% (1370/121,539) at homologous donation (p = 0.17). Follow-up was available for 199 of these donors and 10 additional donors with fetal monitoring. Infant morbidity and mortality rates were not higher than expected; 0.5% (1/214) was stillborn. Although 11% (24/209) of deliveries was associated with autologous transfusion, only 4.3% (9/209) would have had a hemoglobin level less than 8 gm/dl without transfusion. Patients with placenta previa had the highest incidence of transfusion, 83% (5/6). Transfusion incidence was higher for women donating within 1 week of delivery, 21% (8/38), versus 9.4% (16/171) for women donating earlier in pregnancy (p = 0.044). We recommend that donation be completed by 2 weeks before the estimated date of confinement to allow for recovery of red cell mass.