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Background: The incidence of acute kidney injury in pregnancy (P-AKI) is rising and is associated with detrimental maternal and foetal outcomes. Ethnic disparities in pregnancy outcomes are well recognized, with females who identify as Black or Asian being more likely to die during pregnancy compared to females who identify as White ethnicity., Methods: This study reports rates of P-AKI and associated risk factors in pregnant females of different ethnicities. All pregnancies were recorded between 2016 and 2020. AKI episodes were identified using electronic alerts. Ethnicity, AKI stage (1-3), obstetric outcomes and risk factors for P-AKI (chronic hypertension, pregnancy-induced hypertension and pre-eclampsia, and haemorrhage) were assessed., Results: There were 649 P-AKI episodes from 16,943 deliveries (3.8%). Black females were more likely to have P-AKI (5.72%) compared to those who were White (3.12%), Asian (3.74%), mixed ethnicity (2.89%) and Other/Not Stated (3.10%). Black females, compared to White females, were at greater risk of developing P-AKI if they had haemorrhage requiring blood transfusion (OR 2.44, 95% CI 1.31,4.54; p < 0.001) or pregnancy-induced hypertension (OR 1.79, 95% CI 1.12, 2.86; p < 0.001). After adjusting for risk factors, Black females had increased risk of developing P-AKI (OR 1.52, 95% CI 1.22, 1.80; p < 0.001) compared to White females. Black females were at increased risk of developing P-AKI compared to White females. Mode of delivery, pregnancy-induced hypertension and haemorrhage are likely to have contributed. The increased risk persists despite accounting for these variables, suggesting that other factors such as socioeconomic disparities need to be considered., Conclusions: The incidence of P-AKI is likely higher than previously stated in the literature. However, caution must be exercised, particularly with AKI stage 1, as the KDIGO system is not validated in pregnancy and gestational changes in renal physiology need to be considered. Pregnancy-specific AKI definitions are needed., (© 2023. The Author(s) under exclusive licence to Italian Society of Nephrology.)

Chronic hypertension complicates 1% to 2% of pregnancies, and it is increasingly common. Women with chronic hypertension are an easily recognized group who are in touch with a wide variety of healthcare providers before, during, and after pregnancy, mandating that chronic hypertension in pregnancy be within the scope of many practitioners. We reviewed recent data on management to inform current care and future research. This study is a narrative review of published literature. Compared with normotensive women, women with chronic hypertension are at an increased risk of maternal and perinatal complications. Women with chronic hypertension who wish to be involved in their care can do by measuring blood pressure at home. Accurate devices for home blood pressure monitoring are now readily available. The diagnostic criteria for superimposed preeclampsia remain problematic because most guidelines continue to include deteriorating blood pressure control in the definition. It has not been established how angiogenic markers may aid in confirmation of the diagnosis of superimposed preeclampsia when suspected, over and above information provided by routinely available clinical data and laboratory results. Although chronic hypertension is a strong risk factor for preeclampsia, and aspirin decreases preeclampsia risk, the effectiveness specifically among women with chronic hypertension has been questioned. It is unclear whether calcium has an independent effect in preeclampsia prevention in such women. Treating hypertension with antihypertensive therapy halves the risk of progression to severe hypertension, thrombocytopenia, and elevated liver enzymes, but a reduction in preeclampsia or serious maternal complications has not been observed; however, the lack of evidence for the latter is possibly owing to few events. In addition, treating chronic hypertension neither reduces nor increases fetal or newborn death or morbidity, regardless of the gestational age at which the antihypertensive treatment is started. Antihypertensive agents are not teratogenic, but there may be an increase in malformations associated with chronic hypertension itself. At present, blood pressure treatment targets used in clinics are the same as those used at home, although blood pressure values tend to be inconsistently lower at home among women with hypertension. Although starting all women on the same antihypertensive medication is usually effective in reducing blood pressure, it remains unclear whether there is an optimal agent for such an approach or how best to use combinations of antihypertensive medications. An alternative approach is to individualize care, using maternal characteristics and blood pressure features beyond blood pressure level (eg, variability) that are of prognostic value. Outcomes may be improved by timed birth between 38 0/7 and 39 6/7 weeks' gestation based on observational literature; of note, confirmatory trial evidence is pending. Postnatal care is facilitated by the acceptability of most antihypertensives (including angiotensin-converting enzymes inhibitors) for use in breastfeeding. The evidence base to guide the care of pregnant women with chronic hypertension is growing and aligning with international guidelines. Addressing outstanding research questions would inform personalized care of chronic hypertension in pregnancy., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Introduction: Prenatal recognition of dilated aortic root is extremely rare and there are significant challenges in counselling these patients. The primary aim of this case series is to describe the prevalence, associations and outcome of dilated ascending aorta diagnosed during fetal life., Methods: This is a retrospective cohort study from two tertiary fetal cardiology centres. Dilated ascending aorta was defined as gestation-specific standard deviation > 1.96 at some point during gestation., Results: Sixteen infants were live born and underwent postnatal echocardiography. Prenatally suspected bicuspid aortic valve (BAV) (n = 6) was confirmed in 5 cases (83%) postnatally. Thirteen children have been followed up for a period of minimum one year. No connective tissue disease was found., Conclusions: Prenatal dilated ascending aorta is a rare finding (0.06%). It is associated with BAV in 37% of cases and extracardiac abnormalities in 15.7%. Nuchal translucency measurement was >3.5 in 13% of cases. Connective tissue disease was not diagnosed postnatally. This is the largest prenatal cohort with dilated ascending aorta and postnatal outcomes to date. We showed a postnatal persistence of ascending aortic dilatation in 43% of babies. In the absence of extra-cardiac abnormalities, medium term outcome appears good but postnatal surveillance of aortic dilation is required., (© 2021 John Wiley & Sons Ltd.)

Preeclampsia at term accounts for half of maternal deaths from hypertensive disorders. We aimed to assess differences in maternal cardiac indices at 35 +0 to 36 +6 weeks' gestation between women who subsequently developed preeclampsia at term compared with those with uncomplicated pregnancy and to evaluate whether cardiac indices offer incremental prognostic value to the available screening algorithm for preeclampsia. We recruited 1602 women with singleton pregnancies who attended for a routine hospital visit at 35 +0 to 36 +6 weeks' gestation between April and November 2018. We recorded maternal characteristics and preeclampsia-risk-score derived from a competing risks model and measured cardiac indices. Preeclampsia developed in 3.12% (50/1602) of participants. Women with preeclampsia, compared with those without, had increased mean arterial pressure (97.6, SD, 5.53 versus 87.9, SD, 6.82 mm Hg), systemic vascular resistance (1500, interquartile range, 1393-1831 versus 1400, interquartile range, 1202-1630 PRU) and preeclampsia-risk-score (23.4, interquartile range, 9.13-40 versus 0.9, interquartile range, 0.32-3.25). Multivariable analysis demonstrated independent association between the incidence of preeclampsia and E/e' (hazard ratio, 1.19/unit [95% CI, 1.03-1.37]; P =0.018) as well as left ventricular mass indexed for body surface area (hazard ratio, 1.03/[g·m 2 ] [95% CI, 1.003-1.051]; P =0.029). Women with E/e' ≥7.3 and left ventricular mass indexed for body surface area ≥63.2 g/m 2 had an increased risk for developing preeclampsia, despite low preeclampsia-risk-score <5% (hazard ratio, 20.1 [95% CI, 10.5-38.7], P <0.001). Increased left ventricular mass and E/e' offer incremental information to available scoring systems and better stratify women at risk of developing preeclampsia at term.

Objective To explore whether the average price of houses per postcode sector [sector house average prices (SHAP)] is related to perinatal outcomes and whether gestational age would be lower and mortality higher in the least expensive areas compared to the most expensive. Methods All neonatal unit admissions at King's College Hospital from 1/1/2012 to 31/12/2016 were reviewed. The SHAP was retrieved from the Land Registry and the population was divided in equal quintiles with quintiles 1 and 5 representing the most and least expensive areas, respectively. Gestational age and birth weight z-score were collected. Mortality was defined as death before discharge from neonatal care. Results Three thousand three hundred and sixty infants were included and divided in quintiles consisting of 672 infants. Gestational age was lower in quintile 5 compared to all other quintiles (adjusted P<0.001). Birthweight z-score was not significantly different between the quintiles. The SHAP was lower in the infants who died before discharge (n=92) compared to the SHAP of the infants who were alive at discharge (n=3268) (P<0.001). Infants of quintile 5 had 6 times higher risk of death before discharge from neonatal care compared to infants of quintile 1. Conclusion Low SHAPs were associated with poorer perinatal outcomes suggesting SHAP could potentially be used in perinatal populations to determine socio-economic status and associated outcomes.

Admission to neonatal care causes separation of infants from their parents, can adversely affect breast-feeding and is associated with painful procedures. Our aim was to identify perinatal factors and cost of care associated with transient neonatal hyperinsulinaemic hypoglycaemia (HH). Infants born after 35 weeks of gestation admitted because of hypoglycaemia were studied. The neonates were divided into two groups (HH and non-HH), and their length and cost of care were compared and perinatal factors predicting those outcomes explored. Forty of the 474 infants admitted with hypoglycaemia were diagnosed with HH. The HH group had a lower median (IQR) glucose level on admission compared to the non-HH group (p < 0.001). The median (IQR) cost of stay was higher in the HH group (p < 0.001). In the HH group, the GIR max was significantly correlated with cost of stay (p < 0.001). GIR max predicted a cost of stay > £9140 with an area under the ROC curve of 0.956. GIR max  > 13.9 mg/kg/min predicted admission cost > £9140 with 86% sensitivity and 93% specificity.Conclusion: Transient neonatal HH was associated with a higher length and cost of stay in infants admitted for hypoglycaemia. The GIR max can predict the length and cost of stay. What is Known: • Neonatal hypoglycaemia is the leading cause of term and late preterm neonatal admissions. • Hyperinsulinism (HH) is the commonest cause of persistent hypoglycaemia, and delay in the diagnosis and management can have a detrimental impact on long-term development. What is New: • We have demonstrated prior to NICU admission that blood glucose concentrations were lower in infants with HH compared to those without. • The maximum GIR had a stronger correlation with total length and cost of hospital stay compared to insulin levels in HH infants.

Objective: To compare the degree of impaired placentation in women with and those without chronic hypertension (CH) who develop pre-eclampsia (PE) in pregnancy., Methods: Data were derived from prospective screening for adverse pregnancy outcomes in women with singleton pregnancy attending their first routine hospital visit at 11 + 0 to 13 + 6 weeks' gestation. This visit included recording of maternal characteristics and medical history and measurement of mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI), serum placental growth factor (PlGF) and serum pregnancy-associated plasma protein-A (PAPP-A). The measured biomarkers were converted to multiples of the median (MoM) after adjustment for pregnancy characteristics. MoM values in women with CH who developed PE (n = 283) were compared to those of women without CH who developed PE (n = 2236)., Results: In both groups with and without CH, measurements of MAP and UtA-PI were increased, whereas those of PlGF and PAPP-A were decreased and the deviation from normal in all biomarkers decreased with advancing gestational age at delivery with PE. There was no significant difference between women with and those without CH in the slope of the regression line of log 10 MoM biomarker values against gestational age at delivery with PE for any of the biomarkers. However, there was a significant difference in the intercepts and coefficients of biomarkers in the two groups; compared to those without CH, MAP MoM, PlGF MoM and PAPP-A MoM were higher and UtA-PI MoM was lower in the CH group (all P < 0.01)., Conclusion: In pregnancies that develop PE, the degree of impaired placentation, reflected in high UtA-PI and low PlGF and PAPP-A at 11-13 weeks' gestation, is less in women with CH than in those without CH. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd., (Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.)

Objective: To investigate maternal cardiac adaptation in the first trimester of pregnancy with increasing maternal parity., Methods: This was a cross-sectional study carried out at the antenatal clinic of a teaching hospital. We examined 4689 pregnant women at 11 + 0 to 13 + 6 weeks of gestation, performing two-dimensional echocardiography of the maternal left ventricle. There were 2352 parous and 2337 nulliparous women. The relationships between parity, maternal cardiac function and neonatal birth weight were analyzed., Results: Parous compared to nulliparous women had a significantly higher median cardiac output (5.6 vs. 5.2 L/min) and median cardiac index (2.3 vs. 2.1 L/min/m(2)). This was owing to a significantly higher median stroke volume (73.5 vs. 70.5 mL), heart rate (76 vs. 75 bpm), left ventricular outflow diameter (20.4 vs. 20.0 mm) and lower total vascular resistance (1190.8 vs. 1253.7 dyne s/cm(5)) and median uterine artery pulsatility index (1.6 vs. 1.7). Mean arterial blood pressure was not significantly different between the groups. There was a progressive increase in all maternal cardiac variables, apart from total peripheral resistance, which decreased with increasing parity. Birth weight was higher in parous compared to nulliparous women (3.39 vs. 3.23 kg) and it was independently related to maternal hemodynamic variables and demographic and social characteristics (age, height, weight, ethnicity, smoking)., Conclusion: Pregnancy in parous compared to nulliparous women is characterized by higher maternal cardiac output and birth weight., ((c) 2008 ISUOG.)

Objective: To determine the prevalence of blood pressure inter-arm difference (IAD) in early pregnancy and to investigate its possible association with maternal characteristics., Design: A cross-sectional observational study., Setting: Routine antenatal visit in a university hospital., Population: A total of 5435 pregnant women at 11-14 weeks of gestation., Methods: Blood pressure was taken from both arms simultaneously with a validated automated device., Main Outcome Measures: The presence of inter-arm blood pressure difference of 10 mmHg or more., Results: The IAD in systolic and diastolic blood pressure was 10 mmHg or more in 8.3 and 2.3% of the women, respectively. Systolic IAD was found to be significantly related to systolic blood pressure and pulse pressure, and diastolic IAD was found to be significantly related to maternal age, diastolic blood pressure and pulse pressure. The systolic and diastolic IAD were higher in the hypertensive group compared with the normotensive group and absolute IAD increased with increasing blood pressure. About 31.0 and 23.9% of cases of hypertension would have been underreported if the left arm and the right arm were used, respectively, in measuring the blood pressure., Conclusions: There is a blood pressure IAD in a significant proportion of the pregnant population, and its prevalence increases with increasing blood pressure. By measuring blood pressure only on one arm, there is a one in three chance of underreporting hypertension. Therefore, it would be prudent that during the booking visit blood pressure should be taken in both arms and thus provide guidance for subsequent blood pressure measurements during the course of pregnancy.

Objective: To determine the performance of screening for pre-eclampsia by maternal characteristics, urine albumin concentration and albumin-to-creatinine ratio (ACR) at 11(+0) to 13(+6) weeks., Design: Prospective cross-sectional observational study., Setting: Routine antenatal visit., Population: A total of 2679 pregnant women at 11(+0) to 13(+6) weeks of gestation., Methods: Maternal variables, urine albumin concentrations and ACR of 51 women who developed pre-eclampsia were compared with 2364 women who were unaffected by hypertensive disorders. Regression analysis was used first to determine which of the factors among the maternal characteristics were significant predictors of urine albumin concentration and ACR in the unaffected group and second to determine the contribution of urine albumin concentration and ACR in the prediction of pre-eclampsia., Main Outcome Measures: Development of pre-eclampsia., Results: In the unaffected group, log urine albumin concentration and log ACR were influenced by ethnic origin, age, body mass index (BMI), parity and smoking. In the prediction of pre-eclampsia, significant contributions were provided by log urine albumin concentration, log ACR, ethnic origin, BMI, age, family and history of pre-eclampsia. The median urine albumin concentration and the median ACR in the pre-eclampsia group were significantly higher than those in the unaffected group. However, in screening for pre-eclampsia, the area under the receiver operating characteristic curve was not significantly improved by the combined models than with maternal variables alone. The value of urine albumin concentration was not improved by correcting for the creatinine concentration., Conclusion: In the prediction of pre-eclampsia, urine albumin concentration at 11(+0) to 13(+6) weeks does not provide additional value to maternal variables.

This study reports on the interdependence of intra-individual blood pressure (BP) variability and the BP level in early pregnancy. The higher the BP, the more exaggerated the drop from the first to the second reading and the higher the intra-individual standard deviation.

Objective: To investigate maternal cardiac output in the first trimester as a predictor of preeclampsia and delivery of small for gestational age (SGA) infants., Methods: In women attending for routine care between 11(+0) and 13(+6) weeks of gestation, we recorded maternal variables and measured cardiac output by echocardiography. We compared cardiac output in those that developed preeclampsia (n=83), pregnancy-induced hypertension (PIH) (n=87), or SGA (n=532) with those unaffected by preeclampsia, PIH, or SGA (n=3,591). Regression analysis was used to first determine which of the factors among the maternal variables were significant predictors of cardiac output in the unaffected group and, secondly, to predict each complication by a combination of maternal variables and cardiac output., Results: In the unaffected group, cardiac output increased with gestation and maternal weight and decreased with maternal age. Cardiac output was higher in parous women, in cigarette smokers, in those taking antihypertensive or beta-mimetic medications, and in those conceiving after in vitro fertilization, and lower in women of Afro-Caribbean origin. Compared with the unaffected group, cardiac output was significantly higher in the preeclampsia and PIH groups and lower in the SGA group. In screening by cardiac output and maternal variables, for a 10% false-positive rate, the detection rates were 43.4% for all preeclampsia, 52% for preeclampsia without SGA, 23.3% for PIH, and 23.9% for SGA., Conclusion: In pregnancies complicated by preeclampsia, PIH, and SGA, alterations in maternal cardiac output predate the clinical onset of the disorders by several months. Maternal cardiac output in the first trimester is increased in women who develop preeclampsia and decreased in women who deliver SGA infants., Level of Evidence: II.

Objective: To investigate the value of ultrasonographically determined occiput position in the early stages of the active phase of labour, in addition to traditional maternal, fetal and labour-related characteristics, in the prediction of the likelihood of caesarean section., Design: Prospective observational study., Setting: District general hospital in the UK., Population: Six hundred and one singleton pregnancies with cephalic presentation in active labour at term with cervical dilatation of 3-5 cm., Methods: Transabdominal sonography to determine fetal occiput position was carried out by an appropriately trained sonographer immediately before or after the routine clinical examination by the attending midwife or obstetrician., Main Outcome Measure: Caesarean section., Results: Delivery was vaginal in 514 (86%) cases and by caesarean section in 87 (14%). The fetal occiput position was posterior in 209 (35%) cases and in this group the incidence of caesarean section was 19% (40 cases), compared with 11% (47 of 392) in the non-occiput posterior group. Multiple regression analysis revealed that significant independent contribution in the prediction of caesarean section was provided by maternal age (OR 1.1, 95% CI 1.0-1.2), Afro-Caribbean origin (OR 2.4, 95% CI 1.2-4.6), height (OR 0.93, 95% CI 0.89-0.97), parity (OR 0.2, 95% CI 0.1-0.4), type of labour (OR 2.2, 95% CI 1.3-3.8), gestation (OR 1.4, 95% CI 1.1-1.7), fetal head descent (OR 0.6, 95% CI 0.4-0.9), occiput posterior position (OR 2.2, 95% CI 1.3-3.7) and male gender (OR 2.0, 95% CI 1.2-3.5)., Conclusions: The risk of caesarean section can be estimated during the early stage of active labour by the sonographically determined occiput position, in addition to traditional maternal, fetal and labour-related characteristics.

Objective: To determine the effect of pregnancy on respiratory function in a non-Caucasian group and determine whether there was an interaction between pregnancy and altitude of residence., Design: Prospective cross sectional study., Setting: Antenatal clinics in Peru, at sea level in Lima and at high altitude in Cerro de Pasco., Sample: Peruvian women with singleton pregnancies; 122 living at sea level and 192 living at 4300 m altitude in the Peruvian Andes. At each location, 19 non-pregnant women were also studied., Methods: Respiratory function was measured in pregnant and non-pregnant women living at sea level and at 4300 m., Main Outcome Measures: Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow rate (PEFR), total lung capacity (TLC), inspiratory capacity (IC), residual volume (RV), expiratory residual volume (ERV) and functional residual capacity (FRC)., Results: At sea level, RV and TLC were higher in the third compared with the first trimester (P < 0.05). At high altitude, FEV1 (P < 0.01), ERV (P < 0.01) and FRC (P < 0.01) were lower in the third compared with the first trimester. Pregnant and non-pregnant women at high altitude were 4 cm shorter (P < 0.0001) and had larger lung volumes (P < 0.01); their total lung capacities were approximately 1 L greater than women living at sea level (P < 0.0001)., Conclusion: These results suggest that the effect of pregnancy on the respiratory function of healthy women is influenced by altitude of residence.

Objective: To investigate the accuracy of intrapartum transvaginal digital examination in defining the position of the fetal head before instrumental delivery., Patients and Methods: In 64 singleton pregnancies undergoing instrumental delivery the fetal head position was determined by transvaginal digital examination by the attending obstetrician. Immediately after or before the clinical examination, the fetal head position was determined by transabdominal ultrasound by a trained sonographer who was not aware of the clinical findings. The digital examination was considered to be correct if the fetal head position was within +/- 45 degrees of the ultrasound finding. The accuracy of the digital examination was examined in relation to maternal and fetal characteristics., Results: Digital examination failed to define the correct fetal head position in 17 (26.6%) cases. In 12 of 17 (70.6%) errors the difference was >/= 90 degrees and in five (29.4%) the difference was between 45 degrees and 90 degrees. The accuracy of vaginal digital examination was 83% for occiput-anterior and 54% for occiput-lateral + occiput-posterior positions. Logistic regression analysis demonstrated significant independent contributions in explaining the variance in the accuracy of vaginal examination for the station of the fetal head, the position of the fetal head and the experience of the examining obstetrician., Conclusions: Digital examination during instrumental delivery fails to identify the correct fetal head position in about one quarter of cases., (Copyright 2003 ISUOG. Published by John Wiley & Sons, Ltd.)

The impact of pregnancy on respiratory function and whether this is influenced by living conditions, such as altitude of residence, must be determined if the management of pregnant women, particularly those with pulmonary disease is to be optimized. Pulmonary diffusing capacity, corrected for haemoglobin concentration (DL(COc)), therefore, was measured in 112 healthy Peruvian women with singleton pregnancies living at sea level and 192 living at 4300 m. At each location, 19 non-pregnant women were studied. The mean DL(COc)s of the pregnant and non-pregnant women studied at sea level were similar but lower than those of their high altitude counterparts (P<0.001, P<0.001). At high altitude, the mean DL(COc)s of women studied in the first and second trimester were similar to that of non-pregnant women, but the mean DL(COc) of pregnant women studied in the third trimester was lower than that of the non-pregnant women (P<0.01). Our results demonstrate that the effect of pregnancy on pulmonary diffusing capacity is influenced by altitude of residence.

Background: High-altitude (HA) hypoxia leads to profound cardiovascular, respiratory and electrolyte changes, and pregnancy at HA has been associated with increased incidence of preeclampsia and intrauterine growth restriction., Objective: To examine the effect of high altitude on maternal serum electrolytes and liver enzymes., Design: Cross-sectional study of 77 pregnant women at 6-40 weeks of gestation resident at HA (4370 m above sea level) and 80 at sea level (SL) and 13 and 15 nonpregnant women at each altitude, respectively. Serum electrolytes (sodium, potassium, calcium and phosphate), creatinine, bilirubin and liver enzymes (alkaline phosphatase (ALP), aspartate transaminase (AST) and gamma-glutamyl transferase (gamma-GT)) were measured., Results: Pregnancy at HA, compared to SL, was associated with higher serum osmolality (0.4%), sodium (0.7%), creatinine (14%) and phosphate (5%) concentrations and lower potassium (10%) concentration. Calcium and albumin-corrected calcium concentrations were higher at HA compared to SL in nonpregnant women (8%), with no difference in pregnant women. AST, gamma-GT and ALP concentrations were not significantly different between HA and SL, neither in pregnant nor in nonpregnant women. AST and gamma-GT were lower in pregnant compared to nonpregnant women (30%) at HA, whereas the difference was not significant at SL. Total bilirubin concentrations were higher at HA compared to SL by about 25% both in pregnant and in nonpregnant women, the difference reaching statistical significance only in the pregnant group., Conclusions: Pregnancy at HA is associated with increased osmolality, sodium, creatinine, calcium, phosphate and total bilirubin concentrations. Liver enzyme activities are similar to SL., (Copyright 2002 Elsevier Science B.V.)

Objective: To investigate the accuracy of intrapartum transvaginal digital examination in defining the position of the fetal head., Patients and Methods: In 496 singleton pregnancies in labor at term, the fetal head position was determined by routine transvaginal digital examination by the attending midwife or obstetrician. Immediately before or after the clinical examination, the fetal head position was determined using transabdominal ultrasound by an appropriately trained sonographer who was not aware of the clinical findings. The digital examination was considered to be correct if the fetal head position was within 45 degrees of the ultrasound finding. The accuracy of the digital examination was examined in relation to maternal characteristics and the progress of labor., Results: The position of the fetal head was determined by ultrasound examination in all 496 cases examined. Digital examination failed to define the fetal head position in 166 (33.5%) cases and, in 330 cases where the position was determined, the findings of the digital and sonographic examinations were in agreement in only 163 (49.4%) cases. The rate of correct identification of the fetal position by digital examination increased with cervical dilatation, from 20.5% at 3-4 cm to 44.2% at 8-10 cm, and was higher if the examination was carried out by an obstetrician than a midwife (50% versus 30%) and if there was absence rather than presence of caput (33% versus 25%)., Conclusions: Routine digital examination during labor fails to identify the correct fetal position in the majority of cases.

Objective: Singleton pregnancy causes important changes in respiratory function. The incidence of twin pregnancies is increasing, but it is not known whether affected women suffer greater respiratory compromise. The aim of this study was to determine if changes in respiratory function during pregnancy in healthy women were greater in those with a twin pregnancy compared with those with a singleton pregnancy., Design: Cross sectional study., Setting: London teaching hospital., Population: Healthy pregnant women attending the antenatal clinic and ultrasound department., Methods: A cross sectional study of respiratory function was performed in 68 women with twin pregnancies (17 examined in the first trimester, 35 second trimester, 16 third trimester) and 140 women with singleton pregnancies (28, 80, 40, respectively) and 22 non-pregnant women. Women were examined once between 7 and 40 weeks of gestation. Forced vital capacity, relaxed vital capacity, forced expiratory volume in 1 second (FEV1), peak flow, inspiratory capacity, functional residual capacity (FRC), expiratory reserve volume, pulmonary diffusing capacity and minute ventilation were measured., Results: Both in twin and singleton pregnancies, the mean FRC and expiratory reserve ventilation of women studied in the third trimester and minute ventilation of women studied in each trimester differed significantly from that of the non-pregnant women. There were, however, no significant differences demonstrated in respiratory function between healthy women with twin as compared with singleton pregnancies., Conclusion: In healthy women, the extra demands of atwin compared with a singleton pregnancy do not compromise further the respiratory system.

Objective: 1. To measure blood gases and minute ventilation in healthy women with normal pregnancies, compare with non-pregnant women both at sea level and at high altitude; 2. to relate the results at altitude with duration of residence there., Design: Cross-sectional study., Setting: Antenatal clinics at sea level in Lima, Peru and at high altitude 4300m in Cerro de Pasco, Peru., Population: A total of 304 normal pregnant women between 7 and 41 weeks of gestation were studied, including 112 who lived at sea level and 192 at high altitude (4300m). For comparison 38 non-pregnant women (19 at sea level and 19 at high altitude) were also studied., Methods: Arterialised blood gases, haemoglobin, pulse oximetry and minute ventilation were measured once in each woman., Main Outcome Measures: PO2, PCO2, pH, haemoglobin, oxygen saturation, arterial oxygen content and minute ventilation and their relationship to gestation., Results: PO2, PCO2, bicarbonate, base excess and oxygen saturation were lower in pregnancies at high altitude compared with sea level; pH, haemoglobin, arterial oxygen content and minute ventilation were higher. At high altitude oxygen saturation and haemoglobin decreased towards term resulting in a fall in arterial oxygen content at the end of pregnancy. Women whose family had lived at high altitude for at least three generations maintained their oxygenation throughout pregnancy better than women whose family had lived there for less than three generations., Conclusions: In pregnancy at high altitude maternal adaptation appeared adequate in the first trimester but declined towards term. However, maternal oxygenation was maintained in those whose family had lived longest at high altitude suggesting a beneficial adaptation to a hypoxic environment, occurring over generations.

Background: The possible effect of assisted reproduction on first-trimester screening for trisomy 21 was examined by fetal nuchal translucency thickness (NT), maternal serum free beta-human chorionic gonadotrophin (HCG) and pregnancy-associated plasma protein-A (PAPP-A)., Methods: Parameters were measured at 11-14 weeks in 411 singleton pregnancies achieved by controlled ovarian stimulation, including 220 that had undergone IVF. Results were compared with 1233 singleton pregnancies conceived spontaneously., Results: In the IVF pregnancies, the median fetal NT was not significantly different from that in controls, whilst the median free beta-HCG was significantly increased, and PAPP-A was significantly decreased. In the intracytoplasmic sperm injection group, fetal NT and free beta-HCG values were not significantly different from those in controls, but PAPP-A was significantly decreased. In those pregnancies achieved by ovarian stimulation, neither fetal NT, free beta-HCG nor PAPP-A were significantly different from the control group., Conclusions: In IVF pregnancies, screening for trisomy 21 by fetal NT, maternal serum free beta-HCG and PAPP-A levels may be associated with a 1.2% higher false-positive rate than in natural conception.

Objective: To investigate haemorheological changes during pregnancy in a Latin American population and compare to previously published data from Caucasian populations., Design: Cross-sectional study., Population: 75 pregnant women at 10-36 wk of gestation and 17 non-pregnant female controls in Lima, Peru. All the women and their ancestors for three generations were born and lived at sea level., Methods: Viscosity, haematocrit and plasma fibrinogen, albumin and total protein concentrations were determined in blood samples obtained after an overnight period of fasting., Results: At 10 wk of gestation, total protein concentration and plasma viscosity were above non-pregnant levels by about 15% and subsequently decreased linearly with gestation. Fibrinogen concentration was increased in the first trimester; it then decreased to a nadir at about 20 wk and subsequently increased. Albumin concentration decreased linearly with gestation. Haematocrit decreased from pre-pregnancy levels at 10 wk to a nadir at about 26 wk. Blood viscosity increased in the first trimester and then decreased with gestation to a nadir at about 26 wk., Conclusion: In the first trimester of pregnancy blood and plasma viscosity are increased and they subsequently fall with advancing gestation. Plasma viscosity reflects the changes in total protein concentration, and blood viscosity is dependent on the interplay of changes in plasma viscosity and haematocrit.