[Fetal RHD in maternal plasma in prenatal follow-up].

Since the beginning of RHD genotyping in maternal plasma, no Rh D positive baby was diagnosed RHD negative in our institution. Genotyping from circulating DNA in maternal plasma is as efficient as genotyping on amniocyts but without the associated risks. We propose a prophylactic injection based on fetal genotyping RHD in maternal blood with 300 microg anti-D immunoglobulin at 28 weeks of amenhorrea in all of Rh D negative pregnant women whitch fetuses positive RHD.