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Background and Objectives: Non-invasive assays for predicting foetal blood group status in pregnancy serve as valuable clinical tools in the management of pregnancies at risk of detrimental consequences due to blood group antigen incompatibility. To secure clinical applicability, assays for non-invasive prenatal testing of foetal blood groups need to follow strict rules for validation and quality assurance. Here, we present a multi-national position paper with specific recommendations for validation and quality assurance for such assays and discuss their risk classification according to EU regulations. Materials and Methods: We reviewed the literature covering validation for in-vitro diagnostic (IVD) assays in general and for non-invasive foetal RHD genotyping in particular. Recommendations were based on the result of discussions between co-authors. Results: In relation to Annex VIII of the In-Vitro-Diagnostic Medical Device Regulation 2017/746 of the European Parliament and the Council, assays for non-invasive prenatal testing of foetal blood groups are risk class D devices. In our opinion, screening for targeted anti-D prophylaxis for non-immunized RhD negative women should be placed under risk class C. To ensure high quality of non-invasive foetal blood group assays within and beyond the European Union, we present specific recommendations for validation and quality assurance in terms of analytical detection limit, range and linearity, precision, robustness, pre-analytics and use of controls in routine testing. With respect to immunized women, different requirements for validation and IVD risk classification are discussed. Conclusion: These recommendations should be followed to ensure appropriate assay performance and applicability for clinical use of both commercial and in-house assays. (Less)

Background: Doppler ultrasonographic assessment of maternal and foetal blood flow/perfusion has become an indispensable diagnostic tool in veterinary obstetrics. Periodic Doppler examination of critical canine pregnancies to interpret vascular information such as blood velocity, flow direction/pattern and vascular pathologies would ensure safety of dam and survival chances of conceptuses.Methods: The present study included twenty apparently healthy bitches of different breeds presented at University Veterinary Hospital, Thrissur, Kerala for the management of breeding and pregnancy. Doppler examinations were conducted from fourth week of pregnancy at 10 d interval to evaluate blood flow in uteroplacental artery (UPA), umbilical artery (Uma) and foetal abdominal aorta by measuring pulsatility (PI) and resistive indices (RI). Result: Throughout the study the UPA showed biphasic wave. Up to 40 days of gestation the UPA showed diastolic notch and from 41-50 days it disappeared completely. The PI and RI decreased significantly at 5 per cent level between each 10 d interval. Similarly, the PI and RI of Uma decreased significantly at 5 per cent level between each 10 d interval. The PI of foetal abdominal aorta increased significantly at 5 per cent level from £ 30 d to 31-40 d of gestation and thereafter it decreased significantly up to whelping. During early pregnancy the diastolic wave form was absent for Uma and abdominal aorta although at later stages both these vessels showed biphasic wave forms. The study also included the early diagnosis of two abnormal pregnancies, viz., a complete foetal resorption in a Labrador bitch and an incomplete abortion in a Rottweiler bitch by Doppler ultrasound. The incomplete abortion was critically managed and the bitch whelped five healthy puppies fourteen days from the date of the incomplete abortion of three puppies. Thus, the study demonstrated the potential applicability of Doppler Ultrasound in the management of normal and abnormal pregnancies and predicting survival chances of neonates after whelping.

Introduction: Magnesium (Mg) is the second most abundant intracellular cation, and is vital for a multitude of cellular functions and enzymes. Derangement of Mg homeostasis often leads to various diseases such as, Diabetes Mellitus (DM) and Insulin Resistance (IR), hypertension, atherosclerosis and depression. In pregnancy particularly, hypomagnesaemia has been associated with preterm delivery and low birth weight. Aim: To measure maternal and cord blood Mg levels at delivery to calculate the prevalence of hypomagnesaemia in pregnancy, and to correlate Mg levels with other maternal and foetal variables at birth. Materials and Methods: This cross-sectional correlational study was conducted in a 1000- bedded tertiary care centre in Northern India, and consisted of 110 pregnant women admitted for delivery. Maternal and cord blood was obtained at birth and analysed for serum Mg levels. The normality of continuous data was assessed by the Shapiro-Wilk test. Pearson’s correlation analysis was used to determine the relationship between continuous variables. Comparison of means of different groups was done by using unpaired t-test. A p-value

To establish whether foetal blood sampling for pH is a reliable test of foetal acidosis in labour by comparing paired foetal blood samples taken at a single procedure.We conducted a prospective study assessing 293 consecutive attempts at foetal blood sampling in labour over a four month period from February to May 2012. A total of 100 paired samples were suitable for analysis. We compared the consistency of pH results of paired foetal blood samples, evaluated cases where inconsistent results would result in conflicting clinical decisions, and explored factors associated with discordant results.There was a statistically significant difference between the mean pH of the two samples: 7.297 (SD 0.065) versus 7.315 (SD 0.059), p0.0005. Of the 100 paired samples, 43 had a difference greater than the laboratory acceptable maximum analytical difference of 0.038. There was discordance between the samples in 16 cases with results crossing a decision threshold, and in 11 cases (69%) delivery was by emergency caesarean section. Inconsistent results were not associated with specific clinical factors and occurred more often with senior operators.Foetal blood sampling is considered by many as the gold standard in assessing intrapartum foetal wellbeing. We have demonstrated inconsistency of paired foetal blood pH results which suggests that foetal blood sampling should not be considered infallible.

HIV infection is diagnosed using serological tests (detection of HIV1/2-specific antibodies) and tests based on molecular biology techniques (detection of viral nucleic acids: HIV RNA, HIV DNA). Currently, infection with HIV mediated by blood-derived preparations is practically impossible. HIV-specific antibodies pass through placenta to foetal blood, where they may persist till 18th month of life and, therefore, serological tests in children below this age may be falsely positive, which makes establishing a correct diagnosis more difficult. In Poland, only 10% of pregnant women undergo tests aimed to detect infection with HIV while in some Western countries such tests are performed in as many as 98% of pregnant women. During pregnancy in a HIV(+) woman, HIV blood load and number of Th CD4+ lymphocytes should be monitored. In Poland, compulsory tests for presence of HIV infection are performed in persons suspected of HIV infection/AIDS; newborns and infants, pregnant women, carriers and individuals in contact with the infected material.

It is possible to predict most clinically important blood group phenotypes from genomic DNA. Clinical applications include the following: determining foetal blood group to assess risk of haemolytic disease of the foetus and newborn or whether the pregnant woman requires antenatal anti-D prophylaxis; testing multiply transfused and autoimmune haemolytic anaemia patients; defining D variants; detecting donors with very weak D antigens; testing donors and patients when appropriate antisera are not available; RHD zygosity testing; zygosity testing of panel cells; assisting in solving difficult serological problems; and, with the use of high-throughput technologies, extended blood grouping of donors. Over the last 7 years, ISBT Workshops have provided external quality assurance. Future technologies may involve matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and massively parallel (next generation) sequencing.

Zusammenfassung Am geburtsreifen Schafplazentom wurden Reaktionen auf NADH-Tetrazoliumreductase, Cytochromoxydase, Succinatdehydrogenase, NAD-spezifische Isocitratdehydrogenase, Lactatdehydrogenase, Glucose-6-phosphatde-hydrogenase, α-Glycerophosphatdehydrogenase, β-Hydroxybuttersauredehydrogenase, Adenosintriphosphatase, alkalische Phosphatase, Leucinaminopeptidase, Glucose-6-phosphatase sowie auf Glycogen und Mucopolysaccharide durchgefuhrt. Uterussepten und Chorionzotten enthalten relativ wenig Glycogen, welches infolgedessen weder als Reservestoff fur den Eigenbedarf des Plazentoms noch als Zwischenstufe bei der Bereitstellung der fetalen Blutfructose eine besondere Rolle spielt. Nach der Enzymverteilung ist im Chorionepithel ein anaerober, ein aerober und ein direkter (Pentosephosphatzyklus) Glucoseabbau moglich, im mutterlichen Septensyncytium findet dagegen nur ein anaerober Abbau bis zur Milchsaure statt. Einer stark positiven Reaktion auf Adenosintriphosphatase im mutterlichen Septensyncytium steht ein schwacherer Ausfall auf der fetalen Seite gegenuber. Wir deuten diese Verteilung der ATPase als sichtbaren Ausdruck eines intensiven Stoffaustausches zwischen Syncytium und Chorionepithel, wobei die starkere Aktivitat auf der mutterlichen Seite entfaltet wird. Die Anwesenheit von Leucinaminopeptidase in den beiden fetomaternen Kontaktschichten konnte auf einen Prozes hinweisen, bei dem im Syncytium Eiweis zu einfachen Bausteinen abgebaut, anschliesend aktiv zum Trophoblasten transportiert und hier resynthetisiert wird. Summary Histochemical enzyme studies on the sheep placenta at the time of parturition Observations were made on the sheep placenta just before parturition in respect of reactions for glycogen and mucopolysaccharides, as well as the following enzymes NADH-tetrazole-reductase, cytochrome-oxydase, succinate dehydrogenase, NAD-specific isocitrate dehydrogenase, lactate dehydrogenase, glucose-6-phosphate-dehydrogenase, α-glycero-phosphate dehydrogenase, β-hydroxybutyric acid dehydrogenase, adenosine-triphosphatase, alkaline phosphatase, leucine amino-peptidase, and glucose-6-phosphatase. The uterine septa and chorionic villi contained very little glycogen, which suggests that this substance plays no special role either as a reserve foodstuff for the placenta's own needs or as an intermediary substance for the formation of foetal blood fructose. The distribution of enzymes shows that in the chorionic epithelium an anaerobic, an aerobic and a direct (pentose phosphate cycle) glucose breakdown is possible, whereas in the maternal septal syncytium there exists only an anaerobic breakdown as far as lactic acid is concerned. A marked positive reaction for adenosine-triphosphatase in the maternal septal syncytium is in contrast with a much weaker reaction on the foetal side. We interpret this division of adenosine-triphosphatase as a visible expression of an intensive metabolic exchange between the syncytium and the chorion epithelium, whereby the more marked activity occurs on the maternal side. The presence of leucine amino-peptidase in both foeto-maternal contact layers could be seen as a process in which protein in the syncytium is broken down into its simpler components and then actively transported to the trophoblast and resynthesised there. Resume Recherches histochimiques sur les enzymes des cotyledons du mouton au moment de la parturition On effectua sur les cotyledons preleves chez le Mouton au moment de la parturition des reactions permettant de mettre en evidence le glycogene, les mucopolysaccharides et les ferments suivants: NADH-tetrazole-reductase, cytochromoxydase, succinate-dehydrogenase, NAD-isocitrate-dehydrogenase specifique, lactate-dehydrogenase, glucose-6-phosphate-dehydrogenase, α-glycerophosphate-dehydrogenase, β-acide hydroxybutyrique-hydrogenase, adenosine-triphosphatase, phosphatase alcaline, leucine-aminopeptidase, glucose-6-phosphatase. Les cloisons sanguines et les villosites du chorion contiennent relativement peu de glycogene, si bien que ce dernier ne joue un role important ni comme reserve pour les besoins propres des cotyledons, ni comme stade intermediaire dans la preparation du fructose sanguin foetal. Selon la repartition des enzymes dans l'epithelium du chorion, une degradation anaerobie, aerobie et directe (cycle du phosphate de pentose) est possible, alors que dans le syncytium septal de la mere, il ne se produit qu'une degradation anaerobie jusqu'au stade acide lactique. Alors que la reaction a l'adenosine-triphosphatase est fortement positive dans le syncytiom maternel, on ne rencontre qu'une reaction plus faible du cote du foetus. Les auteurs interpretent cette repartition de l'adenosine-triphosphatase comme l'expression visible d'un echange intensif entre le syncytium et l'epithelium du chorion, dans lequel l'activite la plus importante se trouve du cote de la mere. La presence de leucine-aminopeptidase dans les deux couches de contact foeto-maternel pourrait indiquer un processus dans lequel les proteines du syncytium sont degradees jusqu'a un niveau plus simple, puis transportees activement jusqu'aux trophoblastes et resynthetisees. Resumen Estudios enzimaticohistoquimicos en el placentoma ovino maduro para el nacimiento En el placentoma de la oveja, maduro para el nacimiento, se efectuaron reacciones para valorar la NADH-tetrazolioreductasa, citocromooxidasa, succinatodehidrogenasa, NAD-isocitratodehidrogenasa especifica, lactatodehidrogenasa, glucosa-6-fosfatodehidrogenasa, α-glicerofosfatodehidrogenasa, β-dehidrogenasa del acido hidroxibutirico, adenosintrifosfatasa, fosfatasa alcalina, leucinaminopeptidasa, glucosa-6-fosfatasa, asi como el glucogeno y los mucopolisacaridos. Los septos uterinos y las vellosidades del corion contienen poco glucogeno relativamente, el cual por consecuencia no juega un papel especial ni como substancia de reserva para la demanda propia del placentoma ni como fase intermedia en el aprontamiento de la fructosa sanguinea fetal. Con arreglo a la distribucion enzimatica, en el epitelio corionico resulta posible el desdoblamiento anaerobio de la glucosa, el aerobio y el directo (ciclo fosfato de pentosa), mientras que en el sincicio materno de los septos solo se produce una disgregacion anaerobia hasta el acido lactico. A una reaccion fuertemente positiva a la adenosintrifosfatasa en el sincicio materno de los septos se enfrenta un deficit escaso en el lado fetal. Esta distribucion de la ATFasa la interpretamos como expresion visible de un intercambio intenso de substancias entre el sincicio y el epitelio corionico, desarrollandose la actividad mayor en el lado materno. La presencia de leucinaminopeptidasa en ambas capas de contacto feto-maternas podria remitir a un proceso, en el cual en el sincicio se desintegra la proteina hasta simples componentes, que a continuacion son transportados activamente hasta los trofoblastos y se resintetizan alli.

In the foetal erythropoiesis in mouse foetuses, a change from nucleated erythroblasts to anuclear erythrocytes takes place within a period of a little more than 24 hours. This change is due to extrusion of the nuclei. The present findings give rise to the assumption that it would be reasonable to consider the primitive erythroblasts which are characteristic of early foetal erythropoiesis as well as the subsequent definitive erythroblasts to be links in a continued and gradual developmental series, not as two generations of foetal blood cells. The possibility of nuclear extrusion in human foetal erythropoiesis and medullary erythropoiesis is discussed.

Analysis of foetal haemodynamics using Doppler ultrasound is widely applicable in obstetrics in assessing foetal well-being. To evaluate the parameters of foetal circulation we examined 205 pregnant women to ascertain normal velocity ranges of the foetal internal carotid artery and the foetal renal artery. By establishing the ratio between the pulsatility indices of the foetal internal carotid artery, the foetal aorta and the renal artery of the foetus, standards of these were obtained. From this it seems to be possible to gain information on the extent and degree of the centralisation of foetal blood circulation.

The aim of this study was to assess the role of middle cerebral artery peak systolic velocity (MCA-PSV), as measured by doppler ultrasound, in detecting foetal anaemia in Rh- isoimmunised pregnancies. Intra-uterine foetal blood transfusion was performed in such anaemic foetuses to tide over the crisis of foetal immaturity till considered fit for extra-uterine survival.Rh-isoimmunised pregnancies reporting to a tertiary institute from 2003 to 2005, were screened by doppler ultrasound to estimate MCA-PSV to detect foetal anaemia. If the foetus developed MCA-PSV of more than 1.5 multiple of median (MoM) for the gestational age, foetal blood sampling through cordocentesis was performed to confirm foetal anaemia, followed by intrauterine foetal blood transfusion to all anaemic foetuses at the same sitting. Neonatal outcome was evaluated by recording gestational age at the time of delivery, duration of gestational time gained and need for blood transfusion in the neonatal period.A total of thirteen isoimmunised pregnancies were evaluated. Three pregnancies did not require in-utero foetal blood transfusion. Twenty-one intrauterine foetal blood transfusions were performed in the remaining ten patients. Five received blood transfusion in the neonatal period. Intra uterine foetal death occurred in one grossly hydropic foetus and favourable neonatal outcome was recorded in the rest.The clinical outcome of these pregnancies justifies the use of doppler studies of MCA-PSV in detecting foetal anaemia and intra uterine foetal blood transfusion is the only hope of prolonging pregnancy and salvaging such foetuses.

John Hunter's work included description of the nature of digestion, child development, role of the lymphatic system and proof that the maternal and foetal blood supplies are separate. His contribution to the understanding of venereal diseases is reviewed. Hunter’s argument of the unitary nature of venereal diseases is examined and the progress he made in diagnosis and management is discussed.

For a better preservation and identification of Toxoplasma gondii isolates, we propose a new method of freezing of toxoplasma growth in THP-1 cell culture. A cystogenic strain isolated from foetal blood has been grown in these cells and frozen in liquid nitrogen. After thawing, toxoplasma recover the same growth rate and morphology in vitro and the same capacity to form brain cysts into mice compared to the initial strains. The freezing of the cell suspension provides a simple and appropriate method for preservation of Toxoplasma gondii within "bank" isolates.

Newborn piglets were exsanguinated (60% of blood volume) and retransfused 1 h later. One test group received adult pig red blood cells, the other piglet cord blood cells; controls were infused with plasma. While all controls died, satisfactory results were achieved in piglets transfused with either adult or foetal blood. The feasibility of collecting human cord blood for transfusion was assessed in 100 samples of human cord blood. Blood was collected aseptically and aerobic and anaerobic cultures set up. All samples of cord blood were sterile, and all were Mycoplasma negative. Coagulation parameters were analysed in eight cord plasma samples stored at -20 degrees C for 45 days. No significant abnormalities were found immediately after birth or after storage.

The newly synthesised Pβ,–Pγ-difluoromethylenebisphosphonate analogue 2 of nor-carbovir triphosphate is a potent inhibitor of HIV reverse transcriptase; it also exhibits a greatly enhanced stability to dephosphorylation, in foetal blood serum, relative to AZTTP and other nucleoside triphosphates.

Treatment of pregnant mares to prevent abortions due to equine piroplasmosis is a novel idea practised empirically at some Thoroughbred studs in South Africa. This paper presents the results of an investigation to ascertain whether imidocarb dipropionate crosses the equine placenta. Three pregnant mares were injected intramuscularly with imidocarb and their foetuses were mechanically aborted at varying time intervals thereafter. Imidocarb was found in foetal blood at a level similar to that in the dam's blood, suggesting that imidocarb administered to the dam would be available for anti-parasitic activity in the foetal circulation. Uncertainty concerning the time of treatment to achieve the desired effect currently makes this a questionable exercise.

The newly synthesised Pβ,–Pγ-difluoromethylenebisphosphonate analogue 2 of nor-carbovir triphosphate is a potent inhibitor of HIV reverse transcriptase; it also exhibits a greatly enhanced stability to dephosphorylation, in foetal blood serum, relative to AZTTP and other nucleoside triphosphates.

A procedure is described for the detection of specific antimicrobial antibodies in bloodstains. The technique is described and the relationship between antibody concentration and the age of the doner is reported. It is shown that, provided foetal blood can be excluded, an unknown bloodstain may be identified as that of a person over 15 years with a high degree of confidence.

1. The oxygen capacities of foetal and adult blood have been compared by direct measurement of their oxygen and carbon monoxide combining power. Corrections have been applied to the capacities obtained from oxygen content determinations for the presence of carboxyhaemoglobin and methaemoglobin.2. Mean values for the capacities of foetal blood derived from oxygen and carbon monoxide content were 1.312 ml./g (S.E. +/- 0.007) and 1.331 (S.E. +/- 0.002) respectively, while those for adult blood were 1.306 ml./g (S.E. +/- 0.006) and 1.331 (S.E. +/- 0.0005) respectively.3. For neither carbon monoxide nor oxygen was there a significant difference (P > 0.05) of capacity between adult and foetal blood. There was, however, a significant difference (P < 0.05) on comparing the two methods of measurement on each form of blood and values from both methods were significantly different (P < 0.001) from the theoretical value of 1.39 ml. oxygen/g haemoglobin derived from the molecular weight of haemoglobin.4. These results suggest that the International Cyanmethaemoglobin Standard gives values of haemoglobin concentration which are approximately 6% higher than levels indicated by oxygen combining power.

Diaplacental transition of CO is discussed in two cases of lethal CO intoxication of pregnant women. Foetal CO-Hb has a time lag of several hours against maternal CO-Hb. In highly acute CO intoxications noxious foetal CO intoxication may not occur in spite of high maternal CO concentrations. However, there is a possibility of foetal hypoxia based on maternal hypoxaemia. In cases of subacute CO exposure for several hours, higher CO concentrations may be found in the foetal blood than in the maternal blood. Oxygen therapy of such CO intoxication cases must continue for a certain time after the mother had been detoxicated, because foetal CO elimination lags behind that of the mother. Subacute CO intoxications with sublethal CO-Hb concentrations may cause foetal damage and intra-uterine death as a consequence of CO-Hb, cellular toxic CO-effects and the hypoxia caused by maternal hypoxaemia. Medical decision for interruption of pregnancy as a consequence of foetal indication should be taken after due consideration of the legal problems involved in such action.

Summary Placental transfer of chlorthalidone has been shown in subjects suffering from pre-eclampsic toxaemia of pregnancy. Drug levels in the foetal blood are shown to be about 15% of those in the maternal blood and a model has been developed to explain these observations based on differences in the concentration of carbonic anhydrase in the foetal and maternal circulations. As a result of this work it has been possible to comment on the usefulness of chlorthalidone in diuretic treatment of toxaemia of pregnancy.

SUMMARY The methaemoglobinaemia induced by prilocaine administered as a continuous epidural analgesic to women in labour has been examined. At delivery the level of methaemoglobin present in both the maternal and foetal blood was found to be similar in most of the ten cases examined. The decline in methaemoglobinaemia after birth of two infants born with high methaemoglobin levels (14.2 and 16 per cent) was examined. In both cases the level fell to very low values within 24 hours (2 and 3.7 per cent respectively). A parallel study was carried out on cats in labour when it was found that administration of prilocaine to the mother produced virtually no methaemoglobin in the foetus, illustrating the species difference of this response. Cats were chosen because they are particularly sensitive to the methaemoglobin formation induced by aromatic amines and amides.

Pudendal block with 20 ml of 1 per cent lidocaine (200 mg) with and without epinephrine was used in 24 patients for pain relief during the second stage of labour. The addition of epinephrine improved the quality and prolonged the duration of the anasthe-sia. Measurable amounts of lidocaine were detected in maternal venous And foetal scalp blood within 5 minutes after the injection with peak levels within 10-20 minutes. Lidocaine with epinephrine gave lower maternal and foetal levels than plain lidocaine. The peak levels were about 30 per cent lower in maternal and about 20 per cent lower in foetal blood when epinephrine was added to the solution injected. The lidocaine levels in foetal blood were lower than the corresponding concentrations in maternal blood. They were always far below levels reported to be toxic. No correlation existed between maternal or foetal blood lidocaine concentrations and acid-base changes in maternal or foetal blood. A slight but transient decline in the uterine activity was some...

The content of carbon monoxide in maternal and in foetal blood was studied at various times after exposure to CO in concentrations sufficient to produce COHb levels of about 15 per cent in the mother's blood. CO diffused slowly from maternal to foetal blood. When exposure to CO was brief, the readings in foetal blood did not attain the levels to which the concentrations in maternal blood had fallen until 3 to 5 hours after exposure. Even when sufficient CO was breathed to maintain the maternal COHb at about 15 per cent for 2 hours, the content of CO was still not quite so high in foetal as in maternal blood. The disappearance of CO was somewhat slower from foetal blood than from maternal blood.

The radiographic control of an intra-uterine foetal blood transfusion has been described. A preliminary amniogram is performed followed by the introduction of a catheter into the foetal peritoneum. The recognition of an incorrectly placed catheter has been described.

In regard to phosphorus partition, the same general relationship holds between the blood of lambs and of the mother ewes, as between the blood of calves and the mother cows. Total phosphorus is about twice as high in lamb blood as in maternal blood, inorganic phosphorus about twice as high, and organic acid-soluble phosphorus about three times as high. A considerable proportion of an acid-insoluble phosphorus fraction, probably nuclein, may be present in the red corpuscles of lamb blood and may even be present in foetal blood. The organic acid-soluble fraction is confined to the corpuscles, both in young blood and adult blood, but i n one case of a six-month calf foetus a small proportion was noted in plasma.