Fetal Medicine Center Research Articles

Fetal plasma erythropoietin in pregnancies complicated by maternal diabetes mellitus

Our purpose was to investigate the relationship between fetal plasma erythropoietin concentration and measures of short-term and long-term glycemic control and fetal oxygenation in pregnancies complicated by maternal diabetes mellitus. A cross-sectional study was performed at The Harris Birthright Research Centre for Fetal Medicine, London. Cordocentesis was performed in 31 diabetic pregnancies for the measurement of umbilical venous blood pH, PO2, PCO2, lactate and glucose concentration, erythroblast count, hemoglobin, and plasma erythropoietin concentrations. The mean pH was significantly lower and the PCO2, lactate, erythropoietin, hemoglobin, and erythroblast counts were significantly higher than the appropriate normal mean for gestation. There were significant associations between (1) fetal erythropoietin and erythroblast count, (2) fetal erythroblast count and hemoglobin, (3) fetal hemoglobin and maternal glycosylated hemoglobin, and (4) maternal glucose and fetal glucose, pH, and lactate. We postulate that maternal hyperglycemia causes fetal hyperglycemia and acidemia. Increased erythropoietin may be caused by tissue hypoxia or hyperinsulinemia. The increase in fetal hemoglobin may be the consequence of increased erythropoiesis, mediated by either erythropoietin or hyperinsulinemia.

Serum prolactin concentration in normal and small for gestational age fetuses.

To study fetal and maternal serum prolactin concentrations in appropriately-grown (AGA) fetuses and in small for gestational age (SGA) fetuses. A cross-sectional study of 27 AGA and 27 SGA fetuses undergoing cordocentesis for prenatal diagnosis or for determination of fetal karyotype and acid-base balance. Serum prolactin concentration was measured by radioimmunoassay. Harris Birthright Research Centre for Fetal Medicine. In the AGA group, both fetal and maternal serum prolactin concentration increased significantly with gestation (P < 0.001 and P < 0.01, respectively). In the SGA group, the fetal concentration of prolactin was significantly higher (P < 0.05), but the maternal serum prolactin concentration was not different from that of the AGA group. The finding of prolactin in the fetal circulation suggests that the anterior lobe of the pituitary is functioning from at least 12 weeks gestation. The increased serum prolactin concentration in SGA fetuses may be the consequence of hypoglycemic stress on the pituitary or the relative immaturity of the inhibitory hypothalamic-pituitary pathways.

Doppler velocimetry and fetal heart rate studies in nephropathic diabetics

OBJECTIVES: Our objectives were to determine in pregnancies complicated by diabetic nephropathy (1) if impedance to flow in the uterine and umbilical arteries is normal and (2) if these fetuses are hypoxemic and acidemic and if they have decreased fetal heart rate variation and Doppler blood flow redistribution. STUDY DESIGN: In a cross-sectional study at the Harris Birthright Research Centre for Fetal Medicine, London, serial assessment of fetal heart rate variation and Doppler velocimetry of the placental and fetal circulations was undertaken in six pregnancies complicated by diabetic nephropathy. In all cases cordocentesis was performed within 24 hours before delivery for the measurement of umbilical venous blood gases. RESULTS: Cordocentesis demonstrated these fetuses to be hypoxemic and acidemic. The fetal heart rate variation was decreased; however, impedance to flow in the uterine artery was normal, and increased impedance to flow in the umbilical artery with evidence of blood flow redistribution was observed in only one case. CONCLUSIONS: Fetal hypoxemia and acidemia in pregnancies complicated by diabetic nephropathy is not a consequence of impaired placental perfusion, and the degree of metabolic derangement may be obscured by the apparent normal growth and failure of these fetuses to demonstrate blood flow redistribution.

Fetal nuchal translucency: ultrasound screening for chromosomal defects in first trimester of pregnancy.

To examine the significance of fetal nuchal translucency at 10-14 weeks' gestation in the prediction of abnormal fetal karyotype. Prospective screening study. The Harris Birthright Research Centre for Fetal Medicine, King's College Hospital, London. 827 fetuses undergoing first trimester karyotyping by amniocentesis or chorionic villus sampling. Incidence of chromosomal defects. The incidence of chromosomal defects was 3% (28 of 827 cases). In the 51 (6%) fetuses with nuchal translucency 3-8 mm thick the incidence of chromosomal defects was 35% (18 cases). In contrast, only 10 of the remaining 776 (1%) fetuses were chromosomally abnormal. Fetal nuchal translucency > or = 3 mm is a useful first trimester marker for fetal chromosomal abnormalities.

Relations between the fetal circulation and pituitary‐thyroid function

To study the relation between changes in the fetal thyroid hormone and thyroid stimulating hormone (TSH) concentrations and alterations in the fetal circulation as assessed by Doppler ultrasound. A cross-sectional study of small for gestational age (SGA) and red-cell isoimmunized fetuses undergoing cordocentesis and Doppler studies for the assessment and determination of fetal karyotype, acid-base balance and haemoglobin concentration. Harris Birthright Research Centre for Fetal Medicine, King's College, London. 38 growth retarded and 38 red-cell isoimmunised fetuses. Cordocentesis. Serum TSH total and free thyroxine (T4, FT4) and total and free triiodothyronine (T3, FT3) concentrations; middle cerebral artery (MCAVm) and descending thoracic aorta (AoVm) mean blood velocities; fetal Po2 and haemoglobin concentration (Hb). Delta values (delta) calculated as the number of SDs from the respective normal mean for gestation were used to compare the results with those from a previous study of normal fetuses. Mean AoVm was increased in the isoimmunized fetuses (P less than 0.001) but decreased in the SGA fetuses (P less than 0.001). Mean MCAVm was increased in both groups (P less than 0.01; P less than 0.001). There were significant associations between the gestational age adjusted values for TSH and MCAVm (r = 0.23, P less than 0.05) and between T4, FT4 or FT3 and AoVm (r = 0.41, P less than 0.01; r = 0.50, P less than 0.01; r = 0.36, P less than 0.01 respectively). In addition, T4 and FT4 were associated with delta Po2 and delta Hb. In the hypoxaemic hypoxia of growth retardation and the anaemic hypoxia of rhesus disease there are significant associations between changes in fetal thyroid hormone concentrations and changes in fetal blood flow as assessed by Doppler. Irrespective of whether altered blood flow is the cause or effect of changes in thyroid hormone concentrations, the observed changes could have beneficial effects for fetal survival, in the presence of a hostile intrauterine environment.

Prostaglandin levels and fetal breathing activity in pregnancies complicated by premature rupture of the membranes : P.J. Thompson, A. Greenough and K.H. Nicolaides, Dept. of Child Health and Harris Birthright Research Centre for Fetal Medicine, King's College Hospital, London SE5 9RS, U.K.

Prostaglandin levels and fetal breathing activity in pregnancies complicated by premature rupture of the membranes : P.J. Thompson, A. Greenough and K.H. Nicolaides, Dept. of Child Health and Harris Birthright Research Centre for Fetal Medicine, King's College Hospital, London SE5 9RS, U.K.

Effect of Anaemia on Fetal Acid-Base Status

Harris Birthright Research Centre for Fetal Medicine, Department of Obstetrics and Gynaecology, King's College School of Medicine and Dentistry, Denmark Hill, London, England

Ultrasound-Guided Sampling of Umbilical Cord and Placental Blood to Assess Fetal Well-being

Harris-Birthright Research Centre for Fetal Medicine, Department of Obstetrics and Gynaecology, King's College School of Medicine and Dentistry, Denmark Hill, London, England Lancet 1: 1065, 1986

Ultrasound-Guided Sampling of Umbilical Cord and Placental Blood to Assess Fetal Well-being

Harris-Birthright Research Centre for Fetal Medicine, Department of Obstetrics and Gynaecology, King's College School of Medicine and Dentistry, Denmark Hill, London, England Lancet 1: 1065, 1986

Fetal Haematology in Rhesus Isoimmunisation

Harris Birthright Research Centre for Fetal Medicine, Department of Obstetrics and Gynaecology, and Department of Haematology, King's College School of Medicine and Dentistry, London, England