eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2020-09-25 13 3 1215 1220 10.13005/bpj/1989 34961 article Hala A.Youssef 1 Ayman F. Armaneous 2 Hatem M. Hasan 3 Eman R. Youness 4 Marwa W. Abouelnaga 2 Departments of Neonatology, El-Galaa Teaching Hospital. Departments of Neonatology Child Health. Departments of Neonatology Reproductive Health. Departments of Neonatology Medical Biochemistry, National Research Center, Egypt. Endothelin -1 appears to be the predominant member of the family (endothelins ET-1, ET-2 and ET-3), which is exclusively produced by vascular endothelial cells and has the most potent vasoconstrictor activity of all naturally occurring press or substances. Our objective is to evaluate whether Endothelin -1 has a role in altered umbilical arterial blood flow velocity in pregnant mothers with IDDM and its relation to neonatal outcome. 60 pregnant women were recruited for this study and were divided into two groups: 30 IDDM pregnant women with abnormal umbilical Doppler flow velocity waveforms and 30 IDDM pregnant women with normal umbilical artery flow velocity waveform studies. Levels of glycosylated hemoglobin and plasma concentration of ET-1 were determined. Neonatal assessment using the 5 minutes Apgar score and birth weight were estimated; also, plasma level of ET-1 was done for all neonates. A highly significant statistical difference of ET-1 levels between newborns of diabetics with abnormal flow velocity Doppler waveforms and newborns of diabetics with normal Doppler waveforms (P<0.001). In addition, there was a highly significant statistical difference of Apgar score and birth weights between newborns of diabetics with abnormal flow velocity Doppler waveform and newborns of diabetics with normal Doppler waveform. We can conclude that although IDDM pregnant women have markedly elevated ET-1 levels, it is not responsible for the vascular changes associated with abnormal umbilical Doppler studies. Higher neonatal ET-1 levels were associated with low Apgar score in newborns of mothers with abnormal umbilical Doppler studies, suggesting that ET-1 could be a marker of perinatal asphyxia. https://biomedpharmajournal.org/vol13no3/relation-of-endothelin-1-to-abnormal-umbilical-doppler-waveform-studies-in-pregnancies-complicated-by-iddm-and-its-relation-to-the-neonatal-outcome/ Endothelin-1 Umbilical Doppler waveform IDDM pregnant women