BACKGROUND: Hemolytic disease of the fetus and newborn (HDN) is caused primarily by feto-maternal RhD incompatibility. Although all RhD negative pregnant women undergo routine antenatal RhD prophylaxis at 28 weeks of gestation, and following delivery if the newborn is RhD positive, HDN has not been eradicated. Here, we investigated fetal Rhesus D (RHD) genotype in maternal plasma during the first trimester of pregnancy in our area. METHODS: Plasma samples were obtained from 111 RhD negative pregnant women, between 9 and 13 weeks of gestation. DNA from maternal plasma containing cell-free fetal DNA (cffDNA) was analyzed by quantitative PCR (qPCR) to detect RHD exons 5 and 7. A beta-globin (HBB) sequence was quantified to estimate total DNA concentration. qPCR results were compared with newborn RhD determined in cord blood serum. The influence of several gestational parameters on DNA concentration was also analyzed. RESULTS: The specificity and sensitivity of the assay was 93% and 100%, respectively, with 97% diagnostic accuracy. Cell-free DNA concentrations during the first trimester of pregnancy were not affected by the gestational parameters studied (free-beta fraction of human chorionic gonadotropin and pregnancy-associated plasma protein A concentrations, fetal sex, materno-fetal ABO blood group incompatibility, maternal weight and gestational age). CONCLUSIONS: Non-invasive fetal RHD genotyping during the first trimester of pregnancy can be determined with a high specificity, thus representing a valuable tool for improving the management of RhD negative pregnant women. As a high percentage of pregnant women participate in the routine first trimester combined screening program for aneuploidies, the fetal RHD study could be of immediate implementation, since the same blood collection could be used.
BACKGROUND: Hemolytic disease of the fetus and newborn (HDN) is caused primarily by feto-maternal RhD incompatibility. Although all RhD negative pregnant women undergo routine antenatal RhD prophylaxis at 28 weeks of gestation, and following delivery if the newborn is RhD positive, HDN has not been eradicated. Here, we investigated fetal Rhesus D (RHD) genotype in maternal plasma during the first trimester of pregnancy in our area. METHODS: Plasma samples were obtained from 111 RhD negative pregnant women, between 9 and 13 weeks of gestation. DNA from maternal plasma containing cell-free fetal DNA (cffDNA) was analyzed by quantitative PCR (qPCR) to detect RHD exons 5 and 7. A beta-globin (HBB) sequence was quantified to estimate total DNA concentration. qPCR results were compared with newborn RhD determined in cord blood serum. The influence of several gestational parameters on DNA concentration was also analyzed. RESULTS: The specificity and sensitivity of the assay was 93% and 100%, respectively, with 97% diagnostic accuracy. Cell-free DNA concentrations during the first trimester of pregnancy were not affected by the gestational parameters studied (free-beta fraction of human chorionic gonadotropin and pregnancy-associated plasma protein A concentrations, fetal sex, materno-fetal ABO blood group incompatibility, maternal weight and gestational age). CONCLUSIONS: Non-invasive fetal RHD genotyping during the first trimester of pregnancy can be determined with a high specificity, thus representing a valuable tool for improving the management of RhD negative pregnant women. As a high percentage of pregnant women participate in the routine first trimester combined screening program for aneuploidies, the fetal RHD study could be of immediate implementation, since the same blood collection could be used.
Authors: Elena Picchiassi; Gian Carlo Di Renzo; Federica Tarquini; Vittorio Bini; Michela Centra; Luana Pennacchi; Fabiana Galeone; Mara Micanti; Giuliana Coata Journal: Transfus Med Hemother Date: 2014-12-22 Impact factor: 3.747
Authors: Otchere Addai-Mensah; Edward Y Afriyie; Samuel Asamoah Sakyi; Christian Obirikorang; Max Efui Annani-Akollor; Eddie-Williams Owiredu; Francis A Amponsah; Richard Vikpebah Duneeh; Evans Asamoah Adu Journal: Obstet Gynecol Int Date: 2020-10-16