Perinatal mortality in Rh alloimmunized patients.

OBJECTIVE

Evaluate and compare the perinatal mortality of Rh-negative pregnancies managed at São Paulo Federal University during a 9-year period, using either amniocentesis or middle cerebral artery peak systolic velocity.

METHOD

Descriptive observational study involving 291 consecutive Rh-negative pregnancies managed between January 1995 and January 2004. The perinatal mortality of 99 alloimmunized patients was compared with 192 Rh-negative unimmunized patients (control group). The perinatal mortality of patients managed with amniocenteses was compared to those managed with Doppler studies.

RESULTS

There were 74 patients managed with amniocenteses and 25 managed with Doppler studies. Perinatal mortality was significantly higher in the 99 Rh-negative isoimmunized patients than in the 192 unimmunized patients (12.1% versus 1%, p=0.0001) and did not differ according to the management protocol used (amniocentesis 13.5% versus cerebral Doppler 8.0%, p=0.725). Mean gestational age and mean weight at birth in pregnancies managed with amniocenteses (35.7 weeks and 2586 g) did not differ significantly from those managed with Doppler (36.3 weeks and 2647 g).

CONCLUSIONS

Perinatal mortality in Rh-negative alloimmunized patients remains high and does not differ whether pregnancies are managed through amniocentesis or cerebral Doppler evaluation.