[Feto-maternal metabolism in human normal pregnancies: study of 73 cases]. / Métabolisme foeto-maternel au cours de grossesses humaines normales: étude de 73 cas.

From 73 normal pregnancies of gestational age between 17 and 41 weeks of gestation (WG), the concentrations of glucose, pyruvate and lactate, free fatty acids, ketone bodies (aceto-acetate and beta-hydroxybutyrate) and cholesterol were assessed on maternal venous blood (MVB) and umbilical venous blood (UVB), sampled by cordocentesis. The objective of this work was to study feto-maternal metabolism, as well as nutritional exchange between maternal blood and fetal blood during the second and third trimesters of pregnancy. Maternal and fetal glycemias, as well as maternal-fetal glucose concentration gradient, were found stable during the studied gestational period; maternal glucose is always higher than fetal glucose, with a mean concentration delta of 0.69+/-0.34 mmol/L. Maternal lactate level (1.26+/-0.38 mmol/L) is lower than fetal lactate level (1.48+/-0.46 mmol/L), whereas maternal blood pyruvate concentration (0.042+/-0.020 mmol/L) is higher than fetal blood pyruvate concentration (0.025+/-0.010 mmol/L). Consequently, mean lactate / pyruvate ratio is found twice lower in maternal blood (31.77+/-9.89) than in fetal blood (64.10+/-17.12). Free fatty acids concentration is approximately three times higher in maternal blood than in fetal blood (respectively 0.435+/-0.247 mmol/L and 0.125+/-0.046 mmol/L). Maternal venous aceto-acetate (0.051+/-0.042 mmol/L) and beta-hydroxybutyrate (0.232+/-0.270 mmol/L) concentrations are significantly lower than those in UVB (respectively 0.111+/-0.058 and 0.324+/-0.246 mmol/L) and the beta-hydroxybutyrate/aceto-acetate ratio is on average 1.7 times higher in MVB (4.75+/-2.5) than in UVB (2.82+/-1.18). Cholesterol concentration is significantly higher in maternal blood (6.26+/-1.40 mmol/L) than in fetal blood (1.66+/-0.34 mmol/L). Our results show the characteristics of oxidative metabolism of the fetus compared with that of the adult. Blood concentration in energy substrates, measured with glucose and free fatty acids levels, is low in UVB and suggests increased energy needs of the growing fetus. Mean high concentrations in aceto-acetate and beta-hydroxybutyrate in UVB, indicate probably fetal ketogenesis. UVB low cholesterolemia suggests high cholesterol consumption in the fetal compartment for cellular membrane synthesis and steroid biosynthesis.

[Biochemical profile of fetal blood sampled by cordocentesis in 35 pregnancies complicated by growth retardation]. / Etude biochimique du sang foetal prélevé par cordocentèse au cours de 35 grossesses compliquées de retard de croissance.

AIM OF THE STUDY: Intra-uterine growth retardation (IUGR) is a frequent pathology in obstetrics characterized by high heterogeneity. Fetal smallness is sometimes constitutional, but can also be accompanied by fetal distress and vital risks for the infant. In 35 pregnancies complicated by IUGR of different etiologies, we measured on fetal blood obtained by cordocentesis, biochemical variables characteristic of the fetuses' respiratory and metabolic status. The aim of the study was to identify the discriminative biological alterations, related to growth retardation and fetal distress. PATIENTS AND METHODS: The studied population includes 27 cases of severe IUGR, of gestational age 30,2+/-4,6 weeks of gestation (WG) (divided into 20 cases of isolated IUGR and 7 cases of IUGR associated with malformative syndrome), as well as 8 cases of moderate IUGR, of gestational age 26+/-4,5 WG; all fetuses had normal karyotypes. A group of 73 normal fetuses, of gestational age 26,3+/-5,7 WG, constituted a reference population. PH, pCO(2), bicarbonate concentration, pO(2) and SaO(2), as well as glucose, pyruvate, lactate, free fatty acids, aceto-acetate, beta-hydroxybutyrate and cholesterol concentrations were measured on umbilical venous blood (UVB). RESULTS: In case of severe but isolated growth retardation, UVB analysis showed the frequency of acid-base and gasometric disturbances: acidemia and hypoxemia (65% of cases), hypercapnia (60% of cases). Metabolic abnormalities were shown: decrease in glycemia (35% of cases), increase in pyruvatemia and lactatemia (40% of cases), increased free fatty acids serum concentration; a diminution of umbilical venous cholesterol level, the most frequent abnormality, can be seen in 70% of fetuses. In case of severe IUGR associated with malformative syndrome, UVB acid-base and metabolic changes were rarely seen; however, UVB cholesterol level is low in some cases. In case of growth retardation classified as moderate, modifications are relatively not frequent and essentially gasometric. CONCLUSION: In about 60% of cases of severe and isolated IUGR, there is a risk of fetal distress, related to an alteration of the transplacental transfer of respiratory gases and nutritional substrates; chronic fetal malnutrition can be involved, with an impact on the growth of the fetus. In case of IUGR associated with malformative syndrome, fetal smallness is probably a result of intrinsic fetal damage, without nutritional origin.

[Acid-base equilibrium and oxygenation of the human fetus. Study of 73 samples obtained by cordocentesis]. / Equilibre acido-basique et oxygénation du foetus humain. Etude de 73 prélèvements obtenus par cordocentèse.

Acid-base state and oxygenation of fetal blood were evaluated in a group of 73 appropriate for gestational age fetuses between 17 and 41 weeks of gestation; fetal blood was obtained by cordocentesis. We measured, on umbilical venous blood, pH, pCO2, bicarbonates and total CO2, pO2 and percent oxygen saturation; we obtained following results: pH = 7.309 +/- 0.054; pCO2 = 5.99 +/- 0.85 kPa; HCO3 = 22.16 +/- 1.90 mmol/l; total CO2 = 22.53 +/- 1.97 mmol/l; pO2 = 6.02 +/- 1.68 kPa; SaO2 = 0.71 +/- 0.18. In comparison with adult normal values, our results report in fetuses a frequent state of mild and mixed acidosis (in about 80% of cases), rather gazeous; pH is significantly correlated with pCO2 (r = -0.799), moreover there is also a metabolic origin in acidosis. We observed progressive modifications of acid-base state and oxygenation in fetal blood with advancing gestational age: decrease of pH and pO2, increase of pCO2 and bicarbonates; these changes appear mainly from 35th week of gestation, except for bicarbonates, which increase regularly during gestational period we have studied. Fetal acid-base state may be explained by physiological differences due to fetal life conditions, in comparison with adult life conditions. Results obtained in this population of normal fetuses can be considered as reference values for studied parameters.

[Value of an assay of enzymatic activity in amniotic fluid for the detection of fetal anomalies]. / Intérêt du dosage d'activités enzymatiques dans le liquide amniotique pour la détection d'anomalies foetales.

Gamma-glutamyl transpeptidase (GGT), and alkaline phosphatase (ALP) and its intestinal and placental isomers were measured at between 12 and 32 weeks after the LMP in the amniotic fluid of 492 pregnancies, including 400 used to establish normal values. Three cases of trisomy 21, 2 of trisomy 18 and one case of mucoviscidosis were tested. Amniotic GGT decreased during normal pregnancies while total ALP and the intestinal isoenzyme remained stable. These intestinal enzyme levels were lowered in the presence of chromosomal abnormalities (autosomal trisomy) or mucoviscidosis. Levels of these enzymes were determined in 5 multiple pregnancies which culminated in the birth of normal infants.

[Microalbuminuria and pregnancy. Is microalbuminuria predictive of pregnancy toxemia?]. / Microalbuminurie et grossesse. La microalbuminurie est-elle prédictive d'une toxémie gravidique?

Several authors have suggested that estimating the levels of microalbuminuria will help in early screening for pre-eclampsia. The purpose of this work has been to look for the absence of microalbuminuria in normal pregnancies and to work out its predictive value for the risk of toxaemia of pregnancy when it does appear. The study was carried out on 257 women of whom 43 were controls and 214 women who were pregnant and had neither diabetes nor hypertension and had no kidney infections. The samples of urine were gathered in a 12 hour period of night and those that gave a positive reaction for albumin were rejected. RIA techniques were used to work out the levels of albuminuria and these were confirmed by immunoassay. We have compared microalbuminuria, the relationship between urine albumin and creatinine and the clearance of albumin in relationship to albuminuria (as defined by the relationship of albumin and creatinine clearance). We have calculated the sensitivity and the specificity and the prognostic value both positive and negative for these four parameters. Our results show that in a normal pregnancy there should not be any microalbuminuria, and on the other hand that if microalbuminuria does appear according to the four parameters studied, they are all equally sensitive for predicting pre-eclampsia. The relative clearance of albumin from the urine seems to be the most interesting parameter as far as we are concerned, and it could lead to early screening for toxaemia.