The emergence of a change in the prevalence of preeclampsia in a tertiary maternity unit (2004-2016).

BACKGROUND: Pre-eclampsia (PET) affects 2-3% of all pregnancies, rising to 5-7% in nulliparous women. This study aimed to investigate the prevalence of PET over a 13-year period. METHODS: A retrospective review was performed over a 13-year period (2004-2016) via interrogation of the annual clinical reports of The Rotunda Hospital, Dublin. RESULTS: There was a fall in the overall incidence of PET (nulliparous and multiparous), from a peak of 3.8% in 2007 to 1.5% in 2015. Comparing the first and second halves of the study time-period this decrease was statistically significant (p < .0001). In nulliparous women, the thirteen-year mean was 4.4% for the study period, with a similar observed reduction from a peak of 5.3% in 2005 to a trough of 2.4% in 2015. DISCUSSION: In our institution, we have shown a decrease in preeclampsia rates over a 13-year period. While the reason for this trend remains unclear, a similar trend has been observed in another tertiary unit and additional research is required to explain the etiology behind these observations.

Do obstetrics trainees working hours affect caesarean section rates in normal risk women?

OBJECTIVES: The rate of caesarean section (CS) is increasing globally. The nulliparous, term, singleton, vertex presentation, spontaneously labouring woman (Robson Group 1/RG1) is considered low risk for CS. It has been hypothesized that more CS occur at nighttime or at weekends due to doctor fatigue. The European Working Time Directive (EWTD) was implemented in our institution in 2013 to limit doctor working hours, which aimed at reducing fatigue but arguably fractures continuity of care. This study aimed to determine the effect of nocturnal hours and weekend on-call as well as the implementation of EWTD on our RG1 CS rates. STUDY DESIGN: This was a population-based study in a tertiary referral centre from 2008-2017. The inclusion criteria for our study were limited to RG1. Data were analysed from an established clinical database, including mode and time of delivery. Descriptive statistics are presented as number and percent for categorical variables. Relative frequencies were tested using chi-squared test. All statistical analyses were performed using SPSS Version 26. Statistical significance was defined as p < .05. RESULTS: There were 86,473 deliveries over the 10-year study period. There were 18,761 women in RG1. Overall the RG1 CS rate was 12.9 % (n = 2415). Rates of CS in the RG1 were not statistically different between those delivering on weekdays (12.9 %, n = 1726/13,430) and weekends (12.9 %, n = 689/5,331, OR 0.99, 95 % CI = 0.90-1.09, p = .89). During daytime hours the CS rate was 12.1 % (n = 777/6411) and at nighttime was 13.3 % (n = 1638/12,350, OR 1.10, 95 % CI = 1.01-1.21, p = .03). Comparing the time periods pre and post EWTD implementation, there was a significant increase in CS rates (12.1 % n = 1319/10,873 V 13.9 % n = 1096/7,888, OR 1.17, 95 % CI = 1.07-1.27 p < .001). With respect to other modes of delivery in RG1 pre and post EWTD, there was a statistically significant decrease in operative vaginal delivery (OVD) rates (40.1%, n=4,360 V 37.7%, n=2,973, OR 0.90, 95% CI = 0.85-0.95, p = .001) CONCLUSION: This study shows an association between obstetric trainee working practices, RG1 CS and OVD rates; this is most pronounced at night and after the introduction of the EWTD. It is unlikely that obstetric trainee working practices are the only factor related to the increasing CS rate and reduced OVD rate. Consideration should be giving to addressing the needs of obstetric trainees in relation to achieving their competencies with now reduced labour ward exposure. Further study is required to see if alternate arrangements in relation to simulation training could increase the OVD rate and reduce the CS rate.

Reducing emergency cesarean delivery and improving the primiparous experience: Findings of the RECIPE study.

OBJECTIVE: The ability to predict the need for emergency Cesarean delivery holds the potential to facilitate birth choices. The objective of the RECIPE study (Reducing Emergency Cesarean delivery and Improving the Primiparous Experience) was to externally validate a Cesarean delivery risk prediction model. This model, developed by the Genesis study, identified five key predictive factors for emergency Cesarean delivery: maternal age, maternal height, BMI, fetal head circumference (HC) and fetal abdominal circumference (AC). STUDY DESIGN: This prospective, observational study was conducted in two tertiary referral perinatal centers. Inclusion criteria were as follows: primiparous women with a singleton, cephalic presentation fetus in the absence of fetal growth restriction (FGR), oligohydramnios, pre-eclampsia, pre-existing diabetes mellitus or an indication for planned Cesarean delivery. Between 38 + 0 and 40 + 6 weeks' gestational age, participants attended for prenatal assessment that enabled the determination of an individualized risk calculation for emergency Cesarean delivery during labour based on maternal height, BMI, fetal HC and AC, with crucially both participants and care providers being blinded to the resultant risk prediction score. Labor, delivery and postnatal outcomes were ascertained. Calibration and receiver operator curves were generated to determine the predictive capacity for emergency Cesarean delivery of the Genesis risk prediction model in this cohort. RESULTS: 559 primiparous participants were enrolled from May 2017 to April 2019, of whom 142 (25 %) had an emergency Cesarean delivery during labour. Participants with a low predicted risk score (<10 %) had a mean predicted rate of 8% (+/- standard deviation of 2%) and a similarly low actual observed rate of Cesarean delivery (8%). Participants with a high predicted risk (>50 %) had a mean predicted Cesarean delivery rate of 64 % (+/- standard deviation of 9%) and also had a high actual observed Cesarean delivery rate (62 %). The calibration curve and receiver operating characteristic curve demonstrated that this validation study had comparable discriminatory power for emergency Cesarean delivery to that described in the original Genesis study. The Area Under the Curve (AUC) in Genesis was 0.69, whereas the AUC in RECIPE was 0.72, which reflects good predictive capacity of the risk prediction model. CONCLUSION: The accuracy of the Genesis Cesarean delivery prediction tool is supported by this validation study.

The RECIPE study: reducing emergency Caesareans and improving the Primiparous experience: a blinded, prospective, observational study.

BACKGROUND: The RECIPE study aims to validate a risk prediction model for intrapartum caesarean delivery which has been developed by our group. The Genesis study was a prospective observational study carried out by the Perinatal Ireland Research Consortium across 7 clinical centres in Ireland between October 2012 and June 2015. Genesis investigated a range of maternal and fetal parameters in a prospective blinded study of 2336 singleton pregnancies between 39 + 0-41 + 0 weeks' gestational age. This resulted in the development of a risk prediction model for Caesarean Delivery in nulliparous women at term. The RECIPE study now proposes to provide external validation of this risk prediction tool. METHODS: In order to externally validate the model, we aim to include a centre which was not involved in the original study. We propose a trial of risk-assignment for intrapartum caesarean amongst nulliparous women with a singleton pregnancy between 38 + 0 and 40 + 6 weeks' gestational age who are planning a vaginal birth. Results of the risk prediction tool will be concealed from participants and from midwives and doctors providing labour care.. Participants will be invited for an ultrasound scan and delivery details will be collated postnatally. The principal aim of this study is to externally validate the risk prediction model. This prediction model holds the potential to accurately identify nulliparous women who are likely to achieve an uncomplicated vaginal birth and those at high prospect of requiring an unplanned caesarean delivery. DISCUSSION: Validation of the Genesis prediction model would enable more accurate counselling for women in the antenatal setting regarding their own likelihood of requiring an intrapartum Caesarean section. It would also provide valuable personalised information to women about the anticipated course of their own labour. We believe that this is an issue of national relevance that will impact positively on obstetric practice, and will positively empower women to make considered, personalised choices surrounding labour and delivery.

Timing of administration of antenatal magnesium sulfate and umbilical cord blood magnesium levels in preterm babies.

BACKGROUND: The optimum timing of administration of magnesium sulfate (MgSO4) in relation to delivery is not known. The general consensus is to achieve administration to the mother at least 4 hours prior to preterm delivery. OBJECTIVE: To investigate potential predictors of umbilical cord blood magnesium (Mg) concentrations, in particular, timing of antenatal MgSO4 administration in relation to delivery. STUDY DESIGN: A prospective observational study of infants delivered at less than 32 weeks' gestational age. Cord bloods samples were collected at delivery and Mg levels analyzed. RESULTS: Of the 81 included cases, five received no antenatal MgSO4, 65 received a 4 g bolus only, and 11 received a 4 g bolus and 1 g/hour infusion. The median time of bolus administration before delivery was 104 minutes (IQR: 57-215). The mean magnesium level was 0.934 mmol/L in the no antenatal MgSO4 group, 1.018 mmol/L in the bolus only group, and 1.225 mmol/L in the bolus and infusion group (p < .05). In the bolus only group, the highest mean magnesium concentration (1.091 mmol/L) was achieved with administration 1-2 hours before delivery, but the difference was small and not statistically significant. On multiple regression analysis, lower birthweight Z scores and gestational age were independently associated with higher cord blood Mg levels. CONCLUSIONS: In the bolus only group, the highest mean Mg levels were observed with administration 1-2 hours before delivery, but the findings were not statistically significant. Compared to the rest of the cohort, higher Mg levels were found when a bolus was followed by an infusion. Following a MgSO4 bolus, some growth restricted extremely preterm babies may have higher Mg levels than would be otherwise expected.

The Impact of Maternal Gestational Hypertension and the Use of Anti-Hypertensives on Neonatal Myocardial Performance.

BACKGROUND: Assessment of myocardial performance in neonates using advanced techniques such as deformation imaging and rotational mechanics has gained considerable interest. The applicability of these techniques for elucidating abnormal myocardial performance in various clinical scenarios is becoming established. We hypothesise that term infants born to mothers with gestational hypertension (GH) may experience impaired performance of the left and right ventricles during the early neonatal period. OBJECTIVES: We aimed to assess left and right ventricular (LV and RV) function using echocardiography in infants born to mothers with GH and compare them to a control group. METHODS: Term infants (>36+6 weeks) born to mothers with GH underwent assessment to measure biventricular function using ejection fraction (EF), deformation imaging, left-ventricle rotational mechanics (apical rotation, basal rotation, twist, twist rate, and untwist rate), and right ventricle-specific functional parameters (tricuspid annular plane systolic excursion and fractional area change) in the first 48 h after birth. A control group comprising infants born to healthy mothers was used for comparison. RESULTS: Fifteen infants with maternal GH and 30 age-matched controls were enrolled. The GH infants exhibited no differences in birthweight or LV or RV length, but they had lower EF (54 vs. 61%; p < 0.01), LV global longitudinal strain (-20 vs. -25%; p < 0.01), and LV twist (11 vs. 16°; p = 0.04). There were no differences in any of the RV functional parameters. CONCLUSION: Infants born to mothers with GH exhibited lower LV function than healthy controls, while RV function appeared to be preserved. This relationship warrants further exploration in a larger cohort.

Infants Born with Down Syndrome: Burden of Disease in the Early Neonatal Period.

OBJECTIVE: To evaluate the incidence of direct admission of infants with Down syndrome to the postnatal ward (well newborn nursery) vs the neonatal intensive care unit (NICU), and to describe the incidence of congenital heart disease (CHD) and pulmonary hypertension (PH). STUDY DESIGN: This retrospective cohort study of Down syndrome used the maternal/infant database (2011-2016) at the Rotunda Hospital in Dublin, Ireland. Admission location, early neonatal morbidities, outcomes, and duration of stay were evaluated and regression analyses were conducted to identify risk factors associated with morbidity and mortality. RESULTS: Of the 121 infants with Down syndrome, 54 (45%) were initially admitted to the postnatal ward, but 38 (70%) were later admitted to the NICU. Low oxygen saturation profile was the most common cause for the initial and subsequent admission to the NICU. Sixty-six percent of the infants (80/121) had CHD, 34% (41/121) had PH, and 6% died. Risk factors independently associated with primary NICU admission included antenatal diagnosis of Down syndrome, presence of CHD, PH, and the need for ventilation. CONCLUSIONS: Infants with Down syndrome initially admitted to the postnatal ward have a high likelihood of requiring NICU admission. Overall, high rates of neonatal morbidity were noted, including rates of PH that were higher than previously reported. Proper screening of all infants with Down syndrome for CHD and PH is recommended to facilitate timely diagnoses and potentially shorten the duration of the hospital stay.

Non-invasive cardiac output monitoring (NICOM®) can predict the evolution of uteroplacental disease-Results of the prospective HANDLE study.

OBJECTIVES: We aimed to firstly identify the different haemodynamic profiles amongst nulliparous women who develop either gestational hypertension (GH), pre-eclampsia (PE), normotensive fetal growth restriction (FGR) versus unaffected pregnancies using non-invasive cardiac output monitoring (NICOM®). Our second primary objective was to assess the ability of NICOM® derived variables to predict the evolution of PE, GH and FGR. STUDY DESIGN: Low risk nulliparous women were enrolled in a single center prospective observational study. NICOM® assessments were performed at 14, 20 and 28 weeks' gestation and data was obtained on cardiac output (CO), total peripheral resistance (TPR), indexed TPR (adjusted for maternal body surface area; TPRi), stroke volume (SV), indexed SV (adjusted for maternal body surface area; SVi) and heart rate (HR). Logistic regression was used to model GH, PE and FGR with NICOM® measurements as predictors. Linear, non-linear and interaction terms were assessed using the Akaike Information Criterion. RESULTS: The haemodynamic profile of pregnancies complicated by uteroplacental disease- GH (n=18), PE (n=6) and FGR (n=24) were compared to 318 healthy unaffected pregnant controls. Women with evolving PE have a different haemodynamic profile to those developing either GH or FGR. The best independent predictors for the evolution of uteroplacental disease at 14 weeks' gestation were CO in the prediction of FGR (AUC=0.61; p 0.002), TPR in the prediction of GH (AUC=0.63; p<0.02) and SVi in the prediction of PE (AUC=0.62; p<0.05). The performance of haemodynamic variables was enhanced when combined in a multivariate logistic model. We demonstrated that TPR, CO and SV when combined with BP were significant predictors of pregnancies complicated by FGR (AUC=0.64, p=0.004; AUC=0.65, p=0.004; and AUC=0.65, p=0.007 respectively). Whereas in pregnancies complicated by PE, HR and SVi in combination with BP were also statistically significant predictors (AUC=0.75, p=0.017 and AUC=0.77, p=0.007 respectively). CONCLUSIONS: NICOM® derived maternal haemodynamic profile at 14 weeks' gestation has the novel potential to identify pregnancies which will ultimately develop uteroplacental disease.

Outcome following selective fetoscopic laser ablation for twin to twin transfusion syndrome: an 8 year national collaborative experience.

OBJECTIVE: With the recognition of the role of fetoscopic laser ablation for twin to twin transfusion syndrome (TTTS), there is a requirement for auditable standards for this technically challenging and specialized treatment. The purpose of this study is to report on the perinatal and medium-term neurodevelopmental outcomes following an 8-year national single center experience in the management of TTTS using the selective fetoscopic laser ablation technique. STUDY DESIGN: An audit of all cases of TTTS treated with selective laser ablation by a single national fetal medicine team was performed. Overall perinatal survival and medium-term neurodevelopmental outcomes were reported and correlated with gestational age at diagnosis, placental location, volume of amnio-reduction, Quintero staging and percentage inter-twin growth discordance. Procedure-related complications were recorded. RESULTS: The overall fetal survival for the first 105 consecutive cases of TTTS was 61% (128/210 fetuses). Dual survival occurred in 47% (49/105) of cases, and with a single survival rate of 28% (30/105), perinatal survival of least one infant was achieved in 75% (79/105) of cases. No correlation was found between any clinical or sonographic marker and perinatal outcome, although dual survival was noted to be significantly decreased with increasing Quintero stage (p=0.041). Currently, 86% of survivors have been reported to have a normal medium-term neurological outcome. CONCLUSION: Fetoscopic laser ablation is the established optimal treatment for severe twin to twin transfusion syndrome (TTTS). We report comparable short and medium-term outcomes following the selective fetoscopic technique comparing results from our national program with internationally published single-center outcomes, supporting the efficacy and safety of this treatment at our center.

National variations in operative vaginal deliveries in Ireland.

OBJECTIVE: To compare the percentage of operative vaginal delivery (OVD) among all publicly funded maternity hospitals in Ireland and to develop quality control performance tables to facilitate national benchmarking. METHODS: The analysis included deliveries of neonates weighing 500 g or more in publicly funded hospitals in Ireland in 2010. Information was obtained from the Irish National Perinatal Reporting System. Maternities delivering in 1 private hospital or at home, and those with unknown parity were excluded. Mean ± SD OVD rates were calculated per hospital. Quality control tables were devised. RESULTS: In 2010, there were 75600 deliveries, of which 73029 met the inclusion criteria. The number of deliveries per hospital ranged from 1284 to 9759. The OVD rate per hospital was 15.3 ± 2.6% (range, 11.7-20.4%). The OVD rate was 29.1% among primigravidas (n = 30 468) compared with 6.7% among multigravidas (n = 42 561) (P < 0.001). Using quality control tables, 52.6% (n = 10) and 31.6% (n = 6) of hospitals were more than 1 SD outside the national mean for forceps and ventouse delivery, respectively. CONCLUSION: Wide variations were found in both the range of OVD and instrument choice among maternity hospitals in Ireland, raising questions about practice and training in contemporary obstetrics.

Eclampsia: trends in incidence and outcomes over 30 years.

OBJECTIVE: This study set out to describe the incidence, mortality rates, and treatment of eclampsia over a 30-year period in a large urban population. STUDY DESIGN: A detailed report of all pregnancies delivered in the Dublin area from 1977 to 2006 was reviewed for incidence, mortality, and treatment of eclampsia. Almost all pregnancies in this area are managed at one of three major obstetric hospitals. All offer comprehensive antenatal care and operate a restrictive policy to magnesium sulfate prophylaxis, in which MgSO4 is reserved for patients with severe preeclampsia or who have already had an eclamptic seizure. RESULTS: During the 30-year study period, there were a total of 626,929 deliveries. Of the 247 cases of eclampsia (3.9/10,000 deliveries) and four maternal deaths (0.63/100,000 deliveries) attributed to eclampsia, none received MgSO4. The mortality rate due to eclampsia was 1.6% (4/247). The use of MgSO4 increased significantly from 11% (13/115) in the first decade of the study to 88.1% (67/76) in the last decade (p < 0.001). The incidence of eclampsia decreased from 5.4/10,000 in the first decade to 3.5/10,000 in the final decade of the study (p < 0.0001). CONCLUSION: Over the study period, MgSO4 has become the leading antiseizure medication used, and this has led to a significant decrease in rates of eclampsia.

Correlation between birth weight and maternal body composition.

OBJECTIVE: To estimate which maternal body composition parameters measured using multifrequency segmental bioelectric impedance analysis in the first trimester of pregnancy are predictors of increased birth weight. METHODS: Nondiabetic women were recruited after ultrasonographic confirmation of an ongoing singleton pregnancy in the first trimester. Maternal body composition was measured using bioelectric impedance analysis. Multivariable linear regression analysis was performed to identify the strongest predictors of birth weight, with multiple logistic regression analysis performed to assess predictors of birth weight greater than 4 kg. RESULTS: Data were analyzed for 2,618 women, of whom 49.6% (n=1,075) were primigravid and 16.5% (n=432) were obese based on a body mass index (BMI) of 30 or higher. In univariable analysis, maternal age, BMI, parity, gestational age at delivery, smoking, fat mass, and fat-free mass all correlated significantly with birth weight. In multivariable regression analysis, fat-free mass remained a significant predictor of birth weight (model R=0.254, standardized ß=0.237; P<.001), but no relationship was found between maternal fat mass and birth weight. After adjustment for confounding variables, women in the highest fat-free mass quartile had an adjusted odds ratio of 3.64 (95% confidence interval 2.34-5.68) for a birth weight more than 4 kg compared with those in the lowest quartile. CONCLUSIONS: Based on direct measurements of body composition, birth weight correlated positively with maternal fat-free mass and not adiposity. These findings suggest that, in nondiabetic women, interventions intended to reduce fat mass during pregnancy may not prevent large-for-gestational-age neonates and revised guidelines for gestational weight gain in obese women may not prevent large-for-gestational-age neonates. LEVEL OF EVIDENCE: : III.

Endothelial progenitor cells in mothers of low-birthweight infants: a link between defective placental vascularization and increased cardiovascular risk?

CONTEXT: Offspring birthweight is inversely associated with future maternal cardiovascular mortality, a relationship that has yet to be fully elucidated. Endothelial progenitor cells (EPCs) are thought to play a key role in vasculogenesis, and EPC numbers reflect cardiovascular risk. OBJECTIVE: Our objective was to ascertain whether EPC number or function was reduced in mothers of low-birthweight infants. DESIGN AND SETTING: This was a prospective cohort study in a general antenatal department of a university maternity hospital. PARTICIPANTS: Twenty-three mothers of small for gestational age (SGA) infants (birthweight < 10th centile) and 23 mothers of appropriate for gestational age (AGA) infants (birthweight ≥ 10th centile) were recruited. MAIN OUTCOME MEASURES: Maternal EPC number and function, conventional cardiovascular risk markers, and cord blood adiponectin were measured. RESULTS: Median EPC count was lower (294 vs. 367, P = 0.005) and EPC migration was reduced (0.91 vs. 1.59, P < 0.001) in SGA compared with AGA infants, with no difference in EPC adhesion (0.221 vs. 0.284 fluorescence units, P = 0.257). Maternal triglyceride levels were higher in SGA than AGA infants (0.98 vs. 0.78 mmol/liter, P = 0.006), but there was no difference in cholesterol, glucose, insulin, glycosylated hemoglobin, adiponectin, or blood pressure. There was a moderate monotone (increasing) relationship between birthweight and umbilical cord blood adiponectin (r = 0.475, P = 0.005). CONCLUSION: Giving birth to an SGA infant was associated with lower maternal EPC number and reduced migratory function. Cord blood adiponectin was significantly correlated with birthweight.

Placental pathology, birthweight discordance, and growth restriction in twin pregnancy: results of the ESPRiT Study.

OBJECTIVE: We sought to evaluate the association between placental histological abnormalities and birthweight discordance and growth restriction in twin pregnancies. STUDY DESIGN: We performed a multicenter, prospective study of twin pregnancies. Placentas were examined for evidence of infarction, retroplacental hemorrhage, chorangioma, subchorial fibrin, or abnormal villus maturation. Association of placental lesions with chorionicity, birthweight discordance, and growth restriction were assessed. RESULTS: In all, 668 twin pairs were studied, 21.1% monochorionic and 78.9% dichorionic. Histological abnormalities were more frequent in placentas of smaller twins of birthweight discordant pairs (P = .02) and in placentas of small for gestational age infants (P = .0001) when compared to controls. The association of placental abnormalities with both birthweight discordance and small for gestational age was significant for dichorionic twins (P = .01 and .0001, respectively). No such association was seen in monochorionic twins. CONCLUSION: In a large, prospective, multicenter study, we observed a strong relationship between abnormalities of placental histology and birthweight discordance and growth restriction in dichorionic, but not monochorionic, twin pregnancies.

Changes in vaginal breech delivery rates in a single large metropolitan area.

OBJECTIVE: Vaginal breech delivery rates have been accepted widely to be in decline and the Term Breech Trial (TBT) has recommended delivery of a breech-presenting infant by elective cesarean section delivery. Our aim was to examine the rate of vaginal delivery of term breech pregnancies in the 8 years before and after the publication of the TBT. STUDY DESIGN: We retrospectively examined vaginal delivery rates of breech presentations over a 16-year period in 3 large tertiary maternity hospitals that serve a single large metropolitan population. All 3 hospitals are of similar size and serve a population with similar risk profile. We also examined rates of perinatal mortality in the 3 hospitals over the study period. RESULTS: During the 16-year study period, there were 344,259 deliveries among the 3 hospitals; 11,913 of which were breech deliveries. There were 5655 breech deliveries in the 8 years before the publication of the TBT, with a cesarean delivery rate of 76.9%. There were 6258 breech deliveries in the 8 years since publication of the TBT, and the cesarean delivery rate increased to 89.7% (P < .0001). During the 8 years since publication, the rate of vaginal delivery in nulliparous women decreased from 15.3-7.2% (P < .0001). The vaginal breech delivery rate in multiparous women decreased from 32.6-14.8% (P < .0001). The rates of corrected perinatal mortality showed a significant decrease in the last 4 years of the study. CONCLUSION: Our study demonstrates that the results and recommendations of the TBT have contributed to decreasing vaginal breech delivery rates, which were already in decline before its publication.

Early and late preterm delivery rates - a comparison of differing tocolytic policies in a single urban population.

OBJECTIVE: Preterm delivery results in neonatal morbidity and mortality. We set out to estimate the difference in rates of preterm delivery in two institutions, serving a single population, with differing policies regarding use of tocolytic drugs for the prevention of preterm delivery. STUDY DESIGN: A retrospective study comparing preterm delivery rates between 2002 and 2007 in two large tertiary hospitals serving a single urban population with similar risk factor profile located less than 2 miles from each other. During the study period Hospital A routinely used tocolytic therapy, Hospital B operates a policy of never using any tocolytic drugs. Rates of delivery prior to 26, 30, 34 and 37 weeks were compared for each hospital. RESULTS: During the study period there were 90,843 deliveries between the two hospitals. The overall rates of preterm delivery at less than 37 weeks gestation were comparable with 6.62% (2794/42,232) in Hospital A and 6.15% (2989/48,611) in Hospital B (p = 0.99). There was no significant difference in the numbers delivering at less than 34 weeks, 995/42,232 (2.36%) versus 1134/48,611 (2.33%), p = 0.59, less than 30 weeks, 403/42,232 (0.95%) versus 429/48,611 (0.88%), p = 0.87 or prior to 26 weeks, 126/42,232 (0.29%) versus 121/48,611 (0.25%), p= 0.08. CONCLUSION: In this large population routine use of tocolytic drugs in the treatment of threatened preterm labor does not alter rates of early or late preterm delivery. While this study is limited by its retrospective nature, it calls into question the practice of tocolysis.

Placental cord insertion and birthweight discordance in twin pregnancies: results of the national prospective ESPRiT Study.

OBJECTIVE: The purpose of this study was to evaluate the impact of noncentral placental cord insertion on birthweight discordance in twins. STUDY DESIGN: We performed a multicenter, prospective trial of twin pregnancies. Placental cord insertion was documented as central, marginal, or velamentous according to a defined protocol. Association of the placental cord insertion site with chorionicity, birthweight discordance, and growth restriction were assessed. RESULTS: Eight hundred sixteen twin pairs were evaluated; 165 pairs were monochorionic, and 651 pairs were dichorionic. Monochorionic twins had higher rates of marginal (P = .0068) and velamentous (P < .0001) placental cord insertion. Noncentral placental cord insertion was more frequent in smaller twins of discordant pairs than control pairs (29.8% vs 19.1%; P = .004). Velamentous placental cord insertion in monochorionic twins was associated significantly with birthweight discordance (odds ratio, 3.5; 95% confidence interval, 1.3-9.4) and growth restriction (odds ratio, 4; 95% confidence interval, 1.1-14.3). CONCLUSION: Noncentral placental cord insertion contributes to birthweight discordance in monochorionic twin pregnancies. Sonographic delineation of placental cord insertion may be of value in antenatal assessment of twin pregnancies.

Platelet reactivity and pregnancy loss.

OBJECTIVE: We sought to critically evaluate platelet function in recurrent miscarriage (RM). STUDY DESIGN: We conducted a prospective study comparing 30 patients with unexplained recurrent first-trimester pregnancy loss with 30 control subjects matched for age and serum progesterone level. Platelet function was determined using a modified assay of light transmission aggregometry with multiple agonists at different concentrations. Dose-response curves were created and half-maximal effective concentration values were calculated. RESULTS: At test completion the half-maximal effective concentration values for arachidonic acid in the patients with RM were significantly less than in the control subjects (0.153 vs 0.230; P = .0099). The dose-response curves were tightly matched for the other agonists. CONCLUSION: This novel measurement of platelet function has demonstrated that patients with unexplained RM have significantly increased platelet aggregation in response to arachidonic acid. The enhanced response to this agonist provides an empirical rationale for the use of aspirin in management of this clinical condition.