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Background/Objectives:: The incidence of neural tube defects (NTDs) in Ireland has increased in recent years. This study examines knowledge about folic acid (FA) supplementation for the prevention of NTDs among women presenting for antenatal care. Subjects/Methods:: Women were recruited at their convenience in the first trimester after sonographic confirmation of an ongoing singleton pregnancy. A detailed questionnaire was completed under the supervision of a research dietitian. Clinical and socio-demographic details were collected. Results:: Of the 587 women studied, 96% took FA during early pregnancy. Of these, 56.4% cited brain/spinal development or the prevention of brain/spinal defects, spina bifida or NTDs as the reason for taking FA. Multivariate analysis showed that women who were experiencing material deprivation or who were living in Ireland <5 years were least likely to be knowledgeable about the benefits of FA supplementation (P<0.05 for both). Over half (57.1%) of the women did not take FA preconceptionally. The main reason reported for not supplementing preconceptionally was that the woman did not expect to get pregnant (76.4%). Over one-third of women (35%), however, reported that they did not know they needed to take FA before becoming pregnant. Conclusions:: These results highlight the need for a renewed public health campaign in Ireland about the importance of FA. As well as focusing on women who have recently come to live in Ireland, this campaign needs focus on women living in deprivation, as these are the women most at risk of having inadequate knowledge about the importance of FA in improving pregnancy outcomes.

Strong evidence that folic acid (FA) prevents the majority of cases of neural tube defects (NTDs) has led to national organisations developing guidelines for women concerning periconceptional supplementation. In Europe, there is evidence of national variations in the incidence of NTDs, with a recent Irish study reporting an increase in the rate. This review compares the periconceptional FA supplementation guidelines between the different countries in Europe. An online search of country-specific guidelines produced before 2015 concerning periconceptional FA supplementation was conducted. If an English version was not available directly, the EUROCAT register was searched for the English version of the recommendations. We identified national guidelines from 20 European countries. Over half recommended that FA supplements be taken by women planning a pregnancy, but three recommended that they should be taken by all women of child-bearing age. Four guidelines recommended starting FA at least 4 weeks preconceptionally, but no country recommended starting FA at least 12 weeks preconceptionally as suggested by recently published studies. There is a need for further consideration of the duration of preconceptional FA supplementation specifically. The latest scientific evidence in this area should inform the development of European guidelines on FA, as there is wide variation in current recommendations. Overall, the wide variation in national guidelines concerning periconceptional FA supplementation may in part explain the differences in national rates of NTDs reported by EUROCAT. National guidelines on FA supplementation should be standardised across European countries.

INTEGRALhas observed the bright quasar 3C 273 on 3 epochs in January 2003 as one of the first observations of the open programme. The observation on January 5 was simultaneous with RXTEand XMM-Newtonobservations. We present here a first analysis of the continuum emission as observed by these 3 satellites in the band from $\simeq$3 keV to $\simeq$500 keV. The continuum spectral energy distribution of 3C 273 was observed to be weak and steep in the high energies during this campaign. We present the actual status of the cross calibrations between the instruments on the three platforms using the calibrations available in June 2003.

We present the first results on the identifications of a medium sensitivity survey (X-ray flux limit $2\times 10^{-14}\, {\rm erg}\, {\rm cm}^{-2}\, {\rm s}^{-1}$in the 0.5–4.5 keV band) at high galactic latitude (${{\mid}b{\mid}}>20^{\circ}$) carried out with the XMM-Newton X-ray observatory within the AXIS observing programme. This study is being conducted as part of the XMM-Newton Survey Science Centre activities towards the identification of the sources in the X-ray serendipitous sky survey. The sample contains 29 X-ray sources in a solid angle of $0.26\deg^2$(source density $113\pm 21$sources $\deg^{-2}$), out of which 27 (93%) have been identified. The majority of the sources are broad-line AGN (19), followed by narrow emission line X-ray emitting galaxies (6, all of which turn out to be AGN), 1 nearby non-emission line galaxy (NGC 4291) and 1 active coronal star. Among the identified sources we find 2 broad-absorption line QSOs ($z\sim 1.8$and $z\sim 1.9$), which constitute ~10% of the AGN population at this flux level, similar to optically selected samples. Identifications of a further 10 X-ray sources fainter than our survey limit are also presented.

This paper presents the XMM-Newtonfirst-light observations of the Hickson-16 compact group of galaxies. Groups are possibly the oldest large-scale structures in the Universe, pre-dating clusters of galaxies, and are highly evolved. This group of small galaxies, at a redshift of 0.0132 (or 80 Mpc) is exceptional in the having the highest concentration of starburst or AGN activity in the nearby Universe. So it is a veritable laboratory for the study of the relationship between galaxy interactions and nuclear activity. Previous optical emission line studies indicated a strong ionising continuum in the galaxies, but its origin, whether from starbursts, or AGN, was unclear. Combined imaging and spectroscopy with the EPIC X-ray CCDs unequivocally reveals a heavily obscured AGN and a separately identified thermal (starburst) plasma, in NGC 835, NGC 833, & NGC 839. NGC 838 shows only starburst thermal emission. Starbursts and AGN can evidently coexist in members of this highly evolved system of merged and merging galaxies, implying a high probability for the formation of AGN as well as starbursts in post-merger galaxies.

The EPIC focal plane imaging spectrometers on XMM-Newtonuse CCDs to record the images and spectra of celestial X-ray sources focused by the three X-ray mirrors. There is one camera at the focus of each mirror; two of the cameras contain seven MOS CCDs, while the third uses twelve PN CCDs, defining a circular field of view of 30′ diameter in each case. The CCDs were specially developed for EPIC, and combine high quality imaging with spectral resolution close to the Fano limit. A filter wheel carrying three kinds of X-ray transparent light blocking filter, a fully closed, and a fully open position, is fitted to each EPIC instrument. The CCDs are cooled passively and are under full closed loop thermal control. A radio-active source is fitted for internal calibration. Data are processed on-board to save telemetry by removing cosmic ray tracks, and generating X-ray event files; a variety of different instrument modes are available to increase the dynamic range of the instrument and to enable fast timing. The instruments were calibrated using laboratory X-ray beams, and synchrotron generated monochromatic X-ray beams before launch; in-orbit calibration makes use of a variety of celestial X-ray targets. The current calibration is better than 10% over the entire energy range of 0.2 to 10 keV. All three instruments survived launch and are performing nominally in orbit. In particular full field-of-view coverage is available, all electronic modes work, and the energy resolution is close to pre-launch values. Radiation damage is well within pre-launch predictions and does not yet impact on the energy resolution. The scientific results from EPIC amply fulfil pre-launch expectations.

We present XMM-Newtonobservations of the high redshift ($z=3.104$), radio-loud quasar PKS 0537-286. The EPIC CCD cameras provide the highest signal-to-noise spectrum of a high-zquasar to date. The EPIC observations show that PKS 0537-286 is extremely X-ray luminous ($L_{\rm X}=2$1047erg s-1), with an unusually hard X-ray spectrum ($\Gamma=1.27\pm0.02$). The flat power-law emission extends over the whole observed energy range (0.4 to 40 keV in the quasar rest frame); there is no evidence of intrinsic absorption, which has been claimed in PKS 0537-286 and other high zquasars. However, there is evidence for weak Compton reflection. A redshiftediron K line, observed at 1.5 keV - corresponding to ~6.15 keV in the quasar rest frame - is detected at 95% confidence. If confirmed, this is the most distant iron K line known. The line equivalent width is small (33 eV), consistent with the "X-ray Baldwin effect" observed in other luminous quasars. The reflected continuum is also weak ($R \la$0.25). We find the overall spectral energy distribution of PKS 0537-286 is dominated by the X-ray emission, which, together with the flat power-law and weak reflection features, suggests that the X-radiation from PKS 0537-286 is dominated by inverse Compton emission associated with a face-on relativistic jet.

XMM-Newtonobservations of the low luminosity, radio-quiet quasar Markarian 205 have revealed a unique iron K emission line profile. In marked contrast to the broad and redshifted iron K line commonly seen in ASCAobservations of Seyfert 1 galaxies, we find that a substantial amount of the line flux in Mrk 205 occurs above the neutral line energy of 6.4 keV. Furthermore, we find that the iron line emission has two distinct components, a narrow, unresolved neutral line at 6.4 keV and a broadened line centred at 6.7 keV. We suggest that the most likely origin of the 6.7 keV line is from X-ray reflection off the surface of a highly ionised accretion disk, whilst the 6.4 keV component may arise from neutral matter distant from the black hole, quite possibly in the putative molecular torus. Overall this observation underlines the potential of XMM-Newtonfor using the iron K line as a diagnostic of matter in the innermost regions of AGN.

We present XMM-Newtonobservations of the bright quasar PKS 0558-504. The 0.2-10 keV spectrum is dominated by a large, variable soft X-ray excess. The fastest flux variations imply accretion onto a Kerr black hole. The XMM-Newtondata suggest the presence of a "big blue bump"in PKS 0558-504 extending from the optical band to ~3 keV. The soft X-ray spectrum shows no evidence for significant absorption or emission-line features. The most likely explanation for the hot big blue bump is Comptonization by the multi-temperature corona of a thermal accretion disc running at a high accretion rate.

A SAR study on the tertiary alcohol series of phosphodiesterase-4 (PDE4) inhibitors related to 1 is described. In addition to inhibitory potency against PDE4 and the lipopolysaccharide-induced production of TNFα in human whole blood, the binding affinity of these compounds for the human ether-a-go-go related gene (hERG) potassium channel (an in vitro measure for the potential to cause QTc prolongation) was assessed. Four key structural moieties in the molecule were studied, and the impact of the resulting modifications in modulating these activities was evaluated. From these studies, (+)-3d (L-869,298) was identified as an optimized structure with respect to PDE4 inhibitory potency, lack of binding affinity to the hERG potassium channel, and pharmacokinetic behavior. (+)-3d exhibited good in vivo efficacy in several models of pulmonary function with a wide therapeutic index with respect to emesis and prolongation of the QTc interval.

We simulated the use of simultaneous sinusoidal changes of inspired O2 and N2O (Williams et al., J Appl Physiol, 1994; 76: 2130-9) at fractional concentrations up to 0.3 and 0.7, respectively, to estimate FRC and pulmonary blood flow (PBF) during anaesthesia, using O2 as an insoluble indicator. Hahn's approximate equations, which neglect the effect of pulmonary uptake and excretion on expiratory flow, estimate dead space and alveolar volume (VA) with systematic errors less than 10%, but yield systematic errors in PBF which are approximately proportional to FIN2O in magnitude. A correction factor (1 - P)-1 for Hahn's equations for PBF (where P is the mean partial pressure of the soluble indicator) reduces the dependence of PBF estimates of FIN2O, and the solution of equations describing the simultaneous mass balance of both indicators yields accurate results for a wide range of mean FIN2O. However, PBF estimates are sensitive to measurement errors and a third gas must be present to ensure that the indicator gases behave independently.

ABSTRACTDefinitive diagnosis of Johne’s disease in ruminants depends on confirming the presence of the causative bacterium, Mycobacterium aviumsubsp. paratuberculosis, in tissues of the host. This is readily achieved in most ruminant species by culture. However, culture of clinical specimens from sheep in many countries has been unrewarding. Such a culture from sheep was achieved recently in Australia by using a radiometric culture medium. The aims of the present study were to evaluate the culture of M. aviumsubsp. paratuberculosisfrom sheep by using modified BACTEC 12B radiometric medium, to determine the sensitivity of culture in relation to histopathology, and to evaluate a range of solid media. Culture of M. aviumsubsp. paratuberculosisfrom sheep with Johne’s disease is a sensitive method of diagnosis: intestinal tissues from all 43 animals with multibacillary disease and all 22 animals with paucibacillary disease were culture positive, while 98% of feces from 53 animals with multibacillary disease and 48% of feces from 31 animals with paucibacillary disease were culture positive. Of sheep without histological evidence of Johne’s disease from infected flocks, intestinal tissue from 32% of 41 were culture positive, while feces from 17% of 41 were culture positive. Consequently, culture is recommended as the “gold standard” test for detection of ovine Johne’s disease. Of the wide range of solid media that were evaluated, only modified Middlebrook 7H10 and 7H11 agars, which were very similar in composition to modified BACTEC 12B medium, yielded growth of ovine strains of M. aviumsubsp.paratuberculosis. The sensitivity of detection of M. aviumsubsp. paratuberculosison solid media was slightly lower than that in modified BACTEC 12B radiometric medium. Both egg yolk and mycobactin J were essential additives for growth of ovine strains of M. aviumsubsp.paratuberculosisin both liquid and solid media.

Results obtained during the first six months in orbit of Ariel V with the Leicester Sky Survey are reviewed. Among 80 sources found by a scan of the Milky Way, 16 are new, and 11 UHURU sources in the scanned region are not detected. Some of these sources may be transient. The light curve of Cen X-3 in a binary cycle shows a dip between phase 0.5, and 0.75, and a secondary maximum at the centre of the dip. The dip and the maximum get progressively weaker in the succeeding cycles. These features are interpreted in terms of the stellar wind accretion model. Cyg X-1 observation for 14 days gives a broad minimum around superior conjuction. Four bright transient sources of nova-like light curves have been observed. The light curves and the spectra are given for TrA X-1 (A1524-62) and Tau X-T (A0535+26).

The introduction of the active management of labour in an Irish population has been associated with a low incidence of operative delivery and a decreasing perinatal mortality rate. The basis of this management is, first, a formal and accurate diagnosis of labour and second, the early diagnosis of inefficient uterine action and treatment with oxytocin.We studied its application in a multiracial British population of 200 primigravidae. In the mothers actively managed, the incidence of caesarean section was reduced and the incidence of normal deliveries increased. These results indicate that the principles of active management are applicable to a multiracial population and can result in a decrease in the incidence of operative deliveries.

Eighty-four cases of face presentation and 49 cases of brow presentation occurring over 10 years were reviewed. The incidence was 1 in 942 and 1 in 1616 births respectively. A significantly increased incidence of face and brow presentation was noted in fetuses greater than 42 weeks maturity, and of brow presentation in fetuses weighing more than 4000 g when compared to the hospital population. No other aetiological factor was identified. Forty-nine per cent of face and 24 per cent of brow presentations were not diagnosed until the second stage of labour. The caesarean section rates were 24 per cent in face and 80 per cent in brow presentations. There was a high incidence of fetal distress in the babies with face presentation.

Studies have been made of the effect of Cd2+ on the oxidation rate of C3H8 in 80% H3PO4 at 130d C on platinized Pt electrodes.

In the 10 years 1979 to 1988, there were 27 cases of ruptured uterus in 78 489 deliveries. There was no case in 27 829 primigravidae. In 48 718 multigravidae with unscarred uteruses there were eight cases (0.02 per cent) and in 2842 multigravidae who had previously had caesarean sections there were 19 ruptured uteruses (0.7 per cent). Postpartum haemorrhage was the commonest presentation of rupture of the unscarred uterus while intrapartum fetal distress was the predominant feature in the majority of cases of rupture of the scarred uterus. Oxytocin administration was the most frequently associated feature in women with a previous uterine scar. There were no maternal deaths. Eight of the 27 patients had a caesarean hysterectomy. There were 12 perinatal deaths (45 per cent). Rupture of the uterus still presents a significant clinical problem which must be identified if the associated risks to maternal and fetal well-being are to be reduced.

The obstetric outcome of 192 women who failed to drain amniotic fluid during labour was studied. All the women had ruptured membranes as a consequence of either spontaneous rupture of the membranes before labour or following amniotomy. The latter was performed either at the time of diagnosis of labour in women with spontaneous onset of labour or in order to induce labour. No amniotic fluid was observed at amniotomy or throughout the course of labour. Following delivery of the fetus, 38 per cent of these women drained clear amniotic fluid, 33 per cent continued to have absent amniotic fluid while 29 per cent drained meconium-stained amniotic fluid. When compared with those patients who were observed to drain amniotic fluid during labour or at amniotomy, patients with absent amniotic fluid had a three-fold increase in the incidence of fetal heart rate abnormalities requiring fetal blood sampling, a three-fold increase in forceps delivery and a four-fold increase in caesarean section performed for suspected fetal distress. The finding of absent amniotic fluid early in labour in women with ruptured membranes is a predictor of increased fetal risk and of increased obstetric intervention.

An apparatus used in undergraduate instrumentation teaching is described. A small wind tunnel creates air speeds up to 12 m/s. A Pitot tube is used as a reference against which a hot wire anemometer is compared for linearity and transient response. The experiment serves to introduce non-ideal systems.

The frequency responses of systems used to measure flow and pressure in ventilated infants may differ, and hence affect estimates of resistance and compliance. We estimated resistance and compliance in 16 ventilated mechanical lung models using linear regression while varying the frequency response of the flow measurement system. Lung models comprised combinations of four sections of tubing and four bottles filled with steel wool. The cut-off frequencies of a filter in the flow measurement system were chosen to yield time delays of 0, ±3, ±6, and ±9 ms relative to the pressure signal. When the phase lags in the measurement systems were not equal at 10 Hz, a bias in resistance ≈(relative delay) × (elastance) ensued. The bias in the resistance estimate when resistance is 5 Pa ml−1s and compliance is 2 ml kPa−1is approximately 28% per ms of delay mismatch. Time-shifting the flow data to eliminate the phase discrepancy reduced the resistance bias by 85%. The residual resistance bias was assumed to be due to inappropriate amplitude response. Compliance measurements were affected by less than 8% and less than 2% after time correction of the flow data. Pressure and flow signals must be synchronized to within 1 ms at 10 Hz and the amplitude responses of the measurement systems must be adequate for reliable resistance measurement.

3C273 has been monitored by EXOSAT over the period December 1983 to June 1984 in 4 observations. In the December observation the flux was high and the spectrum showed a power law index of 1.5 changing to 0.9 at~8 keV. In subsequent observations the flux dropped to~40% of its original value and the hard tail disappeared. In the last observation the LE flux increased by a factor of 2 with no accompanying ME flux increase.

A new X-ray image of the galactic plane has been produced using the 45 arcmin square field of view of the Medium Energy Instrument on EXOSAT. This image shows a total of 64 sources including 18 new ones which include the first observation of persistent emission from the globular cluster bursters Terzan 1 and Terzan 5. The most important discovery from this image is a 2° wide ridge of diffuse emission symmetrical about the plane and extending from the galactic centre to 1?=±40°. The spectrum of this emission appears to be hard (a ~ 1.2) with no significant absorption.

1. Automatic equipment for estimating mean body weight was tested on layer replacement pullets on litter and in a cage.2. The automatic method gave as good a record as manual weighing for the purpose of controlling food intake.3. The results suggest that care has to be taken regarding the time period over which the weighing equipment is used.4. It is important that as many records as possible are obtained during a period of the day when body weight is not varying substantially.

The variant surface glycoprotein (VSG) of the African trypanosomes is the major membrane protein of the plasma membrane of the bloodstream stage of the parasite. It is anchored in the plasma membrane by a glycolipid covalently bound to the C-terminal amino acid of the protein. The VSG is released through the action of a phosphatidylinositol-specific phospholipase C that removes dimyristoylglycerol and exposes the carbohydrate antigenic determinant common to all VSGs. Promastigotes of Leishmania have a predominant surface glycoprotein, termed p63, that is anchored in the plasma membrane in a similar way. A water-soluble form of p63 can be generated through the action of phosphatidylinositol-specific phospholipase C from trypanosomes or from Bacillus cereus. Either treatment exposes on the Leishmania p63 an antigenic determinant recognized by antibody prepared against the trypanosomal crossreacting determinant. These findings indicate that p63 and VSG have a common membrane anchor and are structurally related.

Hickner, R. C., J. S. Fisher, P. A. Hansen, S. B. Racette, C. M. Mier, M. J. Turner, and J. O. Holloszy. Muscle glycogen accumulation after endurance exercise in trained and untrained individuals. J. Appl. Physiol.83(3): 897–903, 1997.—Muscle glycogen accumulation was determined in six trained cyclists (Trn) and six untrained subjects (UT) at 6 and either 48 or 72 h after 2 h of cycling exercise at ∼75% peak O2uptake (V˙o2 peak), which terminated with five 1-min sprints. Subjects ate 10 g carbohydrate ⋅ kg−1⋅ day−1for 48–72 h postexercise. Muscle glycogen accumulation averaged 71 ± 9 (SE) mmol/kg (Trn) and 31 ± 9 mmol/kg (UT) during the first 6 h postexercise (P< 0.01) and 79 ± 22 mmol/kg (Trn) and 60 ± 9 mmol/kg (UT) between 6 and 48 or 72 h postexercise (not significant). Muscle glycogen concentration was 164 ± 21 mmol/kg (Trn) and 99 ± 16 mmol/kg (UT) 48–72 h postexercise (P< 0.05). Muscle GLUT-4 content immediately postexercise was threefold higher in Trn than in UT (P< 0.05) and correlated with glycogen accumulation rates (r= 0.66,P< 0.05). Glycogen synthase in the active I form was 2.5 ± 0.5, 3.3 ± 0.5, and 1.0 ± 0.3 μmol ⋅ g−1⋅ min−1in Trn at 0, 6, and 48 or 72 h postexercise, respectively; corresponding values were 1.2 ± 0.3, 2.7 ± 0.5, and 1.6 ± 0.3 μmol ⋅ g−1⋅ min−1in UT (P< 0.05 at 0 h). Plasma insulin and plasma C-peptide area under the curve were lower in Trn than in UT over the first 6 h postexercise (P< 0.05). Plasma creatine kinase concentrations were 125 ± 25 IU/l (Trn) and 91 ± 9 IU/l (UT) preexercise and 112 ± 14 IU/l (Trn) and 144 ± 22 IU/l (UT; P< 0.05 vs. preexercise) at 48–72 h postexercise (normal: 30–200 IU/l). We conclude that endurance exercise training results in an increased ability to accumulate muscle glycogen after exercise.

This study of 383 consecutive primiparae given epidural analgesia in labour was conducted to examine the influence of the concentration of bupivacaine on the mode of delivery. The epidural technique and the management of labour were both standardised and the bupivacaine concentration was decided arbitrarily by the duty anaesthetist. Primiparae given 0·25 per cent bupivacaine throughout labour (n = 122) were less likely to require a forceps delivery than primiparae (n = 261) given more than 0.25 per cent bupivacaine at any stage during labour (P < 0·05). This was due mainly to a reduction in the incidence of rotational forceps deliveries and occurred despite a higher incidence (P < 0·05) of oxytocin augmentation of contractions during the second stage of labour in mothers receiving high concentration bupivacaine. Low concentration bupivacaine may not only reduce the incidence of forceps deliveries but may also have analgesic benefits if the number of mothers with forceps related pain in the puerperium is reduced.

The use of prophylactic intravenous cephradine to reduce the incidence of infection following caesarean section was examined. The incidence of infection, defined as a pyrexia of more than 37.5oC after the first 24h, was reduced (P<0·01) from 39 per cent in the control patients (n = 100) to 20 per cent in the patients treated with cephradine (n = 101). Cephradine prophylaxis was more effective (P<0.05) at Hammersmith Hospital, where the infection rates were higher (23 per cent in control patients) than at Northwich Park Hospital (controls-16 per cent infections). Stepwise logistic regression analysis indicated that the primary variables which were important in reducing the incidence of infection were the administration of cephradine (P< 0.001) and the pre-operative absence of skin pathogens (P<0.05). The commonest skin pathogen involved was Staphylococcus aureus.

Eighty-four cases of face presentation and 49 cases of brow presentation occurring over 10 years were reviewed. The incidence was 1 in 942 and 1 in 1616 births respectively. A significantly increased incidence of face and brow presentation was noted in fetuses greater than 42 weeks maturity, and of brow presentation in fetuses weighing more than 4000 g when compared to the hospital population. No other aetiological factor was identified. Forty-nine per cent of face and 24 per cent of brow presentations were not diagnosed until the second stage of labour. The caesarean section rates were 24 per cent in face and 80 per cent in brow presentations. There was a high incidence of fetal distress in the babies with face presentation.Face and brow presentations, deflexed cephalic attitudes of the fetus, occur infrequently with an average incidence of 1 in 545 and 1 in 1444 births respectively (Cruikshank and Cruikshank, 1981). These malpresentations can be a source of concern for the clinician who, because of their acknowledged rarity, must rely on the accumulated data of available reports for guidance. The present study was undertaken to analyse and present the experience gained at a busy maternity unit.

The introduction of the active management of labour in an Irish population has been associated with a low incidence of operative delivery and a decreasing perinatal mortality rate. The basis of this management is, first, a formal and accurate diagnosis of labour and second, the early diagnosis of inefficient uterine action and treatment with oxytocin.We studied its application in a multiracial British population of 200 primigravidae. In the mothers actively managed, the incidence of caesarean section was reduced and the incidence of normal deliveries increased. These results indicate that the principles of active management are applicable to a multiracial population and can result in a decrease in the incidence of operative deliveries.In an Irish population, the active management of labour has been associated with a low level of operative intervention and a decreasing perinatal mortality (O'Driscoll and Foley, 1983). This contrasts with British experience where the fall in perinatal mortality has been associated with higher and rising levels of operative delivery, particularly caesarean section. In Northwick Park Hospital in 1983, only 54 per cent of primigravidae had a normal vaginal delivery.The high incidence of operative delivery is disturbing because it suggests that a relatively high proportion of the surgical interference may be unnecessary. Also, women who want to deliver their babies naturally may insist on unsafe alternatives if they are led to believe that their aims cannot be achieved with current hospital practice.We examined whether or not the principles of the active management of labour (O'Driscoll and Meagher, 1980) are applicable in a multiracial British population.

In a random, controlled trial, mothers were allocated to cither the bed or the birthing chair for the second stage of labour. Of 288 primiparae and 348 multiparae, mothers delivered on the chair were more likely to have a postpartum haemorrhage, more likely to have a perineal tear and less likely to have an intact perineum. No evidence was found that the use of the chair was beneficial.

The outcome of pregnancy of more than 28 weeks maturity was studied in 875 mothers aged 40 years or more. No evidence was found that pregnancy in this age group constitutes a serious risk to the mother's health. The perinatal outcome is determined mainly by factors such as social circumstances, reproductive history, panty and haemolytic disease rather than by advanced maternal age. No justification was found for obstetric intervention based solely on the age of the mother.