Prenatal determination of the fetal RhD blood group by multiplex PCR: a 7-year Portuguese experience.

Objectives: This is a retrospective study to evaluate the efficacy and accuracy of the multiplex polymerase chain reaction (PCR) amplification, for early detection of fetuses at risk for hemolytic disease, in the population living in Portugal, and to characterize the RhD-negative individuals at serologic and molecular level.

Methods: 2030 uncultured amniotic fluid samples and 2012 blood samples from the respective RhD-negative pregnant women were studied by multiplex PCR of intron 3/intron 4, exon 7 and 3'UTR. Amniocentesis was performed for a variety of medical indications.