RESUMO
Objective To detect amniotic fluid ABH blood group substances and ABO blood group genotype by the polymerase chain reaction with sequence-specific primers(PCR-SSP) to increase the prenatal diagnosis of fetal ABO blood group .Methods 53 pregnant women with gestational age 16 -25 weeks were selected .Amniotic fluid was extracted for detecting ABH blood group substances by the serological indirect agglutinating reaction ;the amniotic fluid cells were separated for extracting DNA .Then the PCR-SSP technique was adopted to analyze the ABO blood group genotypes .Results 16 specimens of amniotic fluid were non-se-creting type phenotype(30 .2% ) and 37 specimens of amniotic fluid were secreting type phenotype (69 .8% );48 specimens of amni-otic fluid were detected out the ABO blood group genotype by the PCR-SSP method .ABO blood group of fetal amniotic fluid cells by the gene identification was consistent to the detection results of amniotic fluid secreting type ABH blood group substances .Con-clusion The PCR-SSP technique can accurately detect the fetal amniotic fluid cells ABO blood group .