Iatrogenic and spontaneous preterm birth in England: A population-based cohort study.

OBJECTIVE: To describe the rates of and risk factors associated with iatrogenic and spontaneous preterm birth and the variation in rates between hospitals. DESIGN: Cohort study using electronic health records. SETTING: English National Health Service. POPULATION: Singleton births between 1 April 2015 and 31 March 2017. METHODS: Multivariable Poisson regression models were used to estimate adjusted risk ratios (adjRR) to measure association with maternal demographic and clinical risk factors. MAIN OUTCOME MEASURES: Preterm births (<37 weeks of gestation) were defined as iatrogenic or spontaneous according to mode of onset of labour. RESULTS: Of the births, 6.1% were preterm and of these, 52.8% were iatrogenic. The proportion of preterm births that were iatrogenic increased after 32 weeks. Both sub-groups were associated with previous preterm birth, extremes of maternal age, socio-economic deprivation and smoking. Iatrogenic preterm birth was associated with higher body mass index (BMI) (BMI >40 kg/m2 adjRR 1.59, 95% CI 1.50-1.69) and previous caesarean (adjRR 1.88, 95% CI 1.83-1.95). Spontaneous preterm birth was less common in women with a higher BMI (BMI >40 kg/m2 adjRR 0.77, 95% CI 0.70-0.84) and in women with a previous caesarean (adjRR 0.87, 95% CI 0.83-0.90). More variation between NHS hospital trusts was observed in rates of iatrogenic, compared with spontaneous, preterm births. CONCLUSIONS: Just over half of all preterm births resulted from iatrogenic intervention. Iatrogenic births have overlapping but different patterns of maternal demographic and clinical risk factors to spontaneous preterm births. Iatrogenic and spontaneous sub-groups should therefore be measured and monitored separately, as well as in aggregate, to facilitate different prevention strategies. This is feasible using routinely acquired hospital data.

Use of induction of labour and emergency caesarean section and perinatal outcomes in English maternity services: a national hospital-level study.

OBJECTIVES: To assess the association between hospital-level rates of induction of labour and emergency caesarean section, as measures of "practice style", and rates of adverse perinatal outcomes. DESIGN: National study using electronic maternity records. SETTING: English National Health Service. PARTICIPANTS: Hospitals providing maternity care to women between April 2015 and March 2017. MAIN OUTCOME MEASURES: Stillbirth, admission to a neonatal unit, and babies receiving mechanical ventilation. RESULTS: Among singleton term births, the risk of stillbirth was 0.15%; of admission to a neonatal unit 5.4%; and of mechanical ventilation 0.54%. There was considerable between-hospital variation in the induction of labour rate (minimum 17.5%, maximum 40.7%) and the emergency caesarean section rate (minimum 5.6%, maximum 17.1%). Women who gave birth in hospitals with a higher induction of labour rate had better perinatal outcomes. For each 5%-point increase in induction, there was a decrease in the risk of term stillbirth by 9% (OR 0.91; 95% CI 0.85 to 0.97) and mechanical ventilation by 14% (OR 0.86; 95% CI 0.79 to 0.94). There was no significant association between hospital-level induction of labour rates and neonatal unit admission at term (p>0.05). There was no significant association between hospital-level emergency caesarean section rates and adverse perinatal outcomes (p always >0.05). CONCLUSIONS: There is considerable between-hospital variation in the use of induction of labour and emergency caesarean section. Hospitals with a higher induction rate had a lower risk of adverse birth outcomes. A similar association was not found for caesarean section.

Obstetric interventions and pregnancy outcomes during the COVID-19 pandemic in England: A nationwide cohort study.

BACKGROUND: The COVID-19 pandemic has disrupted maternity services worldwide and imposed restrictions on societal behaviours. This national study aimed to compare obstetric intervention and pregnancy outcome rates in England during the pandemic and corresponding pre-pandemic calendar periods, and to assess whether differences in these rates varied according to ethnic and socioeconomic background. METHODS AND FINDINGS: We conducted a national study of singleton births in English National Health Service hospitals. We compared births during the COVID-19 pandemic period (23 March 2020 to 22 February 2021) with births during the corresponding calendar period 1 year earlier. The Hospital Episode Statistics database provided administrative hospital data about maternal characteristics, obstetric inventions (induction of labour, elective or emergency cesarean section, and instrumental birth), and outcomes (stillbirth, preterm birth, small for gestational age [SGA; birthweight < 10th centile], prolonged maternal length of stay (≥3 days), and maternal 42-day readmission). Multi-level logistic regression models were used to compare intervention and outcome rates between the corresponding pre-pandemic and pandemic calendar periods and to test for interactions between pandemic period and ethnic and socioeconomic background. All models were adjusted for maternal characteristics including age, obstetric history, comorbidities, and COVID-19 status at birth. The study included 948,020 singleton births (maternal characteristics: median age 30 years, 41.6% primiparous, 8.3% with gestational diabetes, 2.4% with preeclampsia, and 1.6% with pre-existing diabetes or hypertension); 451,727 births occurred during the defined pandemic period. Maternal characteristics were similar in the pre-pandemic and pandemic periods. Compared to the pre-pandemic period, stillbirth rates remained similar (0.36% pandemic versus 0.37% pre-pandemic, p = 0.16). Preterm birth and SGA birth rates were slightly lower during the pandemic (6.0% versus 6.1% for preterm births, adjusted odds ratio [aOR] 0.96, 95% CI 0.94-0.97; 5.6% versus 5.8% for SGA births, aOR 0.95, 95% CI 0.93-0.96; both p < 0.001). Slightly higher rates of obstetric intervention were observed during the pandemic (40.4% versus 39.1% for induction of labour, aOR 1.04, 95% CI 1.03-1.05; 13.9% versus 12.9% for elective cesarean section, aOR 1.13, 95% CI 1.11-1.14; 18.4% versus 17.0% for emergency cesarean section, aOR 1.07, 95% CI 1.06-1.08; all p < 0.001). Lower rates of prolonged maternal length of stay (16.7% versus 20.2%, aOR 0.77, 95% CI 0.76-0.78, p < 0.001) and maternal readmission (3.0% versus 3.3%, aOR 0.88, 95% CI 0.86-0.90, p < 0.001) were observed during the pandemic period. There was some evidence that differences in the rates of preterm birth, emergency cesarean section, and unassisted vaginal birth varied according to the mother's ethnic background but not according to her socioeconomic background. A key limitation is that multiple comparisons were made, increasing the chance of false-positive results. CONCLUSIONS: In this study, we found very small decreases in preterm birth and SGA birth rates and very small increases in induction of labour and elective and emergency cesarean section during the COVID-19 pandemic, with some evidence of a slightly different pattern of results in women from ethnic minority backgrounds. These changes in obstetric intervention rates and pregnancy outcomes may be linked to women's behaviour, environmental exposure, changes in maternity practice, or reduced staffing levels.

Risk of postpartum haemorrhage is associated with ethnicity: A cohort study of 981 801 births in England.

OBJECTIVE: To determine the association between ethnic group and risk of postpartum haemorrhage in women giving birth. DESIGN: Cohort study. SETTING: Maternity units in England. SAMPLE: A total of 981 801 records of births between 1 April 2015 and 31 March 2017 in a national clinical database. METHODS: Multivariable logistic regression analyses with multiple imputation to account for missing data and robust standard errors to account for clustering within hospitals. MAIN OUTCOME MEASURE: Postpartum haemorrhage of ≥1500 ml (PPH). RESULTS: A total of 28 268 (2.9%) births were complicated by PPH. Risks were higher in women from black (3.9%) and other (3.5%) ethnic backgrounds. Following adjustment for maternal and fetal characteristics, and care at birth, there was evidence of an increased risk of PPH in women from all ethnic minority groups, with the largest increase seen in black women (adjusted OR 1.54, 95% CI 1.45-1.63). The increase in risk was robust to sensitivity analyses, which included changing the outcome to PPH of ≥3000 ml. CONCLUSIONS: In England, women from ethnic minority backgrounds have an increased risk of PPH, when maternal, fetal and birth characteristics are taken into account. Factors contributing to this increased risk need further investigation. Perinatal care for women from ethnic minority backgrounds should focus on preventative measures to optimise maternal outcomes. TWEETABLE ABSTRACT: Women with an ethnic minority background giving birth in England have an increased risk of postpartum haemorrhage, even when characteristics of the mother, the baby and the care received are taken into account.

Adverse pregnancy outcomes attributable to socioeconomic and ethnic inequalities in England: a national cohort study.

BACKGROUND: Socioeconomic deprivation and minority ethnic background are risk factors for adverse pregnancy outcomes. We aimed to quantify the magnitude of these socioeconomic and ethnic inequalities at the population level in England. METHODS: In this cohort study, we used data compiled by the National Maternity and Perinatal Audit, based on birth records from maternity information systems used by 132 National Health Service hospitals in England, linked to administrative hospital data. We included women who gave birth to a singleton baby with a recorded gestation between 24 and 42 completed weeks. Terminations of pregnancy were excluded. We analysed data on stillbirth, preterm birth (<37 weeks of gestation), and fetal growth restriction (FGR; liveborn with birthweight <3rd centile by the UK definition) in England, and compared these outcomes by socioeconomic deprivation quintile and ethnic group. We calculated attributable fractions for the entire population and specific groups compared with least deprived groups or White women, both unadjusted and with adjustment for smoking, body-mass index (BMI), and other maternal risk factors. FINDINGS: We identified 1 233 184 women with a singleton birth between April 1, 2015, and March 31, 2017, of whom 1 155 981 women were eligible and included in the analysis. 4505 (0·4%) of 1 155 981 births were stillbirths. Of 1 151 476 livebirths, 69 175 (6·0%) were preterm births and 22 679 (2·0%) were births with FGR. Risk of stillbirth was 0·3% in the least socioeconomically deprived group and 0·5% in the most deprived group (p<0·0001), risk of a preterm birth was 4·9% in the least deprived group and 7·2% in the most deprived group (p<0·0001), and risk of FGR was 1·2% in the least deprived group and 2·2% in the most deprived group (p<0·0001). Population attributable fractions indicated that 23·6% (95% CI 16·7-29·8) of stillbirths, 18·5% (16·9-20·2) of preterm births, and 31·1% (28·3-33·8) of births with FGR could be attributed to socioeconomic inequality, and these fractions were substantially reduced when adjusted for ethnic group, smoking, and BMI (11·6% for stillbirths, 11·9% for preterm births, and 16·4% for births with FGR). Risk of stillbirth ranged from 0·3% in White women to 0·7% in Black women (p<0·0001); risk of preterm birth was 6·0% in White women, 6·5% in South Asian women, and 6·6% in Black women (p<0·0001); and risk of FGR ranged from 1·4% in White women to 3·5% in South Asian women (p<0·0001). 11·7% of stillbirths (95% CI 9·8-13·5), 1·2% of preterm births (0·8-1·6), and 16·9% of FGR (16·1-17·8) could be attributed to ethnic inequality. Adjustment for socioeconomic deprivation, smoking, and BMI only had a small effect on these ethnic group attributable fractions (13·0% for stillbirths, 2·6% for preterm births, and 19·2% for births with FGR). Group-specific attributable fractions were especially high in the most socioeconomically deprived South Asian women and Black women for stillbirth (53·5% in South Asian women and 63·7% in Black women) and FGR (71·7% in South Asian women and 55·0% in Black women). INTERPRETATION: Our results indicate that socioeconomic and ethnic inequalities were responsible for a substantial proportion of stillbirths, preterm births, and births with FGR in England. The largest inequalities were seen in Black and South Asian women in the most socioeconomically deprived quintile. Prevention should target the entire population as well as specific minority ethnic groups at high risk of adverse pregnancy outcomes, to address risk factors and wider determinants of health. FUNDING: Healthcare Quality Improvement Partnership.

Maternal and perinatal outcomes of pregnant women with SARS-CoV-2 infection at the time of birth in England: national cohort study.

BACKGROUND: Some studies have suggested that women with SARS-CoV-2 infection during pregnancy are at increased risk of adverse pregnancy and neonatal outcomes, but these associations are still not clear. OBJECTIVE: This study aimed to determine the association between SARS-CoV-2 infection at the time of birth and maternal and perinatal outcomes. STUDY DESIGN: This is a population-based cohort study in England. The inclusion criteria were women with a recorded singleton birth between May 29, 2020, and January 31, 2021, in a national database of hospital admissions. Maternal and perinatal outcomes were compared between pregnant women with a laboratory-confirmed SARS-CoV-2 infection recorded in the birth episode and those without. Study outcomes were fetal death at or beyond 24 weeks' gestation (stillbirth), preterm birth (<37 weeks' gestation), small for gestational age infant (small for gestational age; birthweight at the .05) in the rate of other maternal outcomes. The risk of neonatal adverse outcome (adjusted odds ratio, 1.45; 95% confidence interval, 1.27-1.66; P<.001), need for specialist neonatal care (adjusted odds ratio, 1.24; 95% confidence interval, 1.02-1.51; P=.03), and prolonged neonatal admission after birth (adjusted odds ratio, 1.61; 95% confidence interval, 1.49-1.75; P<.001) were all significantly higher for infants with mothers with laboratory-confirmed SARS-CoV-2 infection. When the analysis was restricted to pregnancies delivered at term (≥37 weeks), there were no significant differences in neonatal adverse outcome (P=.78), need for specialist neonatal care after birth (P=.22), or neonatal readmission within 4 weeks of birth (P=.05). Neonates born at term to mothers with laboratory-confirmed SARS-CoV-2 infection were more likely to have prolonged admission after birth (21.1% compared with 14.6%; adjusted odds ratio, 1.61; 95% confidence interval, 1.49-1.75; P<.001). CONCLUSION: SARS-CoV-2 infection at the time of birth is associated with higher rates of fetal death, preterm birth, preeclampsia, and emergency cesarean delivery. There were no additional adverse neonatal outcomes, other than those related to preterm delivery. Pregnant women should be counseled regarding risks of SARS-CoV-2 infection and should be considered a priority for vaccination.

Risk of complicated birth at term in nulliparous and multiparous women using routinely collected maternity data in England: cohort study.

OBJECTIVES: To determine the rate of complicated birth at term in women classified at low risk according to the National Institute for Health and Care Excellence guideline for intrapartum care (no pre-existing medical conditions, important obstetric history, or complications during pregnancy) and to assess if the risk classification can be improved by considering parity and the number of risk factors. DESIGN: Cohort study using linked electronic maternity records. PARTICIPANTS: 276 766 women with a singleton birth at term after a trial of labour in 87 NHS hospital trusts in England between April 2015 and March 2016. MAIN OUTCOME MEASURE: A composite outcome of complicated birth, defined as a birth with use of an instrument, caesarean delivery, anal sphincter injury, postpartum haemorrhage, or Apgar score of 7 or less at five minutes. RESULTS: Multiparous women without a history of caesarean section had the lowest rates of complicated birth, varying from 8.8% (4879 of 55 426 women, 95% confidence interval 8.6% to 9.0%) in those without specific risk factors to 21.8% (613 of 2811 women, 20.2% to 23.4%) in those with three or more. The rate of complicated birth was higher in nulliparous women, with corresponding rates varying from 43.4% (25 805 of 59 413 women, 43.0% to 43.8%) to 64.3% (364 of 566 women, 60.3% to 68.3%); and highest in multiparous women with previous caesarean section, with corresponding rates varying from 42.9% (3426 of 7993 women, 41.8% to 44.0%) to 66.3% (554 of 836 women, 63.0% to 69.5%). CONCLUSIONS: Nulliparous women without risk factors have substantially higher rates of complicated birth than multiparous women without a previous caesarean section even if the latter have multiple risk factors. Grouping women first according to parity and previous mode of birth, and then within these groups according to presence of specific risk factors would provide greater and more informed choice to women, better targeting of interventions, and fewer transfers during labour than according to the presence of risk factors alone.

Neonatal hypoglycaemia: learning from claims.

OBJECTIVES: Neonatal hypoglycaemia is a potential cause of neonatal morbidity, and on rare but tragic occasions causes long-term neurodevelopmental harm with consequent emotional and practical costs for the family. The organisational cost to the NHS includes the cost of successful litigation claims. The purpose of the review was to identify themes that could alert clinicians to common pitfalls and thus improve patient safety. DESIGN: The NHS Litigation Authority (NHS LA) Claims Management System was reviewed to identify and review 30 claims for injury secondary to neonatal hypoglycaemia, which were notified to the NHS LA between 2002 and 2011. SETTING: NHS LA. PATIENTS: Anonymised documentation relating to 30 neonates for whom claims were made relating to neonatal hypoglycaemia. Dates of birth were between 1995 and 2010. INTERVENTIONS: Review of documentation held on the NHS LA database. MAIN OUTCOME MEASURES: Identifiable risk factors for hypoglycaemia, presenting clinical signs, possible deficits in care, financial costs of litigation. RESULTS: All claims related to babies of at least 36 weeks' gestation. The most common risk factor for hypoglycaemia was low birth weight or borderline low birth weight, and the most common reported presenting sign was abnormal feeding behaviour. A number of likely deficits in care were reported, all of which were avoidable. In this 10-year reporting period, there were 25 claims for which damages were paid, with a total financial cost of claims to the NHS of £162 166 677. CONCLUSIONS: Acknowledging that these are likely to be the most rare but most seriously affected cases, the clinical themes arising from these cases should be used for further development of training and guidance to reduce harm and redivert NHS funds from litigation to direct care.

Hypoglycaemia and hypoxic-ischaemic encephalopathy.

The transition from fetal to neonatal life requires metabolic adaptation to ensure that energy supply to vital organs and systems is maintained after separation from the placental circulation. Under normal conditions, this is achieved through the mobilization and use of alternative cerebral fuels (fatty acids, ketone bodies, and lactate) when blood glucose concentration falls. Severe hypoxia-ischaemia is associated with impaired metabolic adaptation, and animal and human data suggest that levels of hypoglycaemia that are tolerated under normal conditions can be harmful in association with hypoxia-ischaemia. The optimal target blood glucose level for ensuring adequate energy provision in hypoxic-ischaemic encephalopathy (HIE) remains unknown. However, recent data support guidance to maintain a blood glucose concentration of 2.5 mmol/L or more in neonates with signs of acute neurological dysfunction, which includes those with HIE, and this is higher than the accepted threshold of 2 mmol/L in infants without signs of neurological dysfunction or hyperinsulinism.

Towards effective capacity planning in a perinatal network centre.

OBJECTIVE: To study the arrival pattern and length of stay (LoS) in a neonatal intensive care/high dependency unit (NICU/HDU) and special care baby unit (SCBU) and the impact of capacity shortage in a perinatal network centre, and to provide an analytical model for improving capacity planning. METHODS: The data used in this study have been collected through the South England Neonatal Database (SEND) and the North Central London Perinatal Network Transfer Audit between 1 January and 31 December 2006 for neonates admitted and refused from the neonatal unit at University College London Hospital (UCLH). Exploratory data analysis was performed. A queuing model is proposed for capacity planning of a perinatal network centre. OUTCOME MEASURES: Predicted number of cots required with existing arrival and discharge patterns; impact of reducing LoS. RESULTS: In 2006, 1002 neonates were admitted to the neonatal unit at UCLH, 144 neonates were refused admission to the NICU and 35 to the SCBU. The model shows the NICU requires seven more cots to accept 90% of neonates into the NICU. The model also shows admission acceptance can be increased by 8% if LoS can be reduced by 2 days. CONCLUSIONS: The arrival, LoS and discharge of neonates having gestational ages of <27 weeks were the key determinants of capacity. The queuing model can be used to determine the cot capacity required for a given tolerance level of admission rejection.

The role of mannose-binding lectin in susceptibility to infection in preterm neonates.

Preterm neonates are susceptible to infection due to a combination of sub-optimal immunity and increased exposure to invasive organisms. Mannose-binding lectin (MBL) is a component of the innate immune system, which may be especially important in the neonatal setting. The objective of this study was to investigate the impact of MBL on susceptibility and severity of infection in preterm neonates during their first month of life. One hundred fifty eight preterm neonates were genotyped for MBL mutations by heteroduplex analyses. Consecutive serum MBL levels were measured by ELISA and clinical and laboratory data, including blood cultures, were collected for each baby. A third of the premature neonates had genetically determined MBL deficiency. In addition, MBL levels were also low in the first week of life and lower in neonates with a wild type genotype who were less than 28 wk gestation or a birth weight of less than 1000 g, thereby increasing the number of neonates with a low MBL level at birth. MBL deficiency was associated with an increased risk of sepsis (p < 0.01). This study indicates that MBL levels are low in neonates at birth and renders premature neonates to an increased risk of infection.

Optimal positions for the release of primitive neonatal reflexes stimulating breastfeeding.

BACKGROUND: Despite widespread skills-teaching, 37% of UK mothers initiating breastfeeding stop by six weeks suggesting a need to reappraise current support strategies. Rooting, sucking and swallowing have been studied extensively but little is known about the role other primitive neonatal reflexes (PNRs) might play to support breastfeeding. AIMS: To describe and compare PNRs observed during feeding, investigating whether certain feeding behaviours and positions, collectively termed Biological Nurturing, (BN) are associated with the release of those reflexes pivotal in establishing successful feeding. METHOD: 40 breastfed healthy term mother/baby pairs were recruited using quota sampling to stratify term gestational age. Feeding sessions were videotaped in the first postnatal month, either in hospital or at home. FINDINGS: 20 PNRs were validated and classified into 4 types (endogenous, motor, rhythmic and anti-gravity) and 2 functional clusters (finding/latching, milk transfer) either stimulating or hindering feeding. Significantly more PNRs were observed as stimulants in semi-reclined postures (BN) than when mothers were upright or side-lying (p=<0.0005). DISCUSSION: This study is the first to describe a range of semi-reclined maternal postures interacting with neonatal positions, releasing maternal instinctual behaviours and PNRs stimulating breastfeeding. Traditionally the human neonate has been considered a dorsal feeder with pressure needed along the baby's back. Compelling visual data here illustrate that the newborn is an abdominal feeder and, like some other animals, displays anti-gravity reflexes aiding latch. Findings suggest that breastfeeding initiation is innate for both mother and baby, not learned, thus challenging the routine skills-teaching currently central to breastfeeding support.

Nutritional factors that affect the postnatal metabolic adaptation of full-term small- and large-for-gestational-age infants.

OBJECTIVE: To document metabolic adaptation to ex utero life in small- (SGA) and large-for-gestational-age (LGA) infants in relation to fetal nutrition and postnatal feeding practices. METHODS: In a prospective study, 65 SGA (< or = second centile) and 39 LGA (> or = 98th centile) full-term infants were recruited. Anthropometry was performed within the first 48 hours. There was full support of breastfeeding and close clinical observation. Blood glucose and ketone body (kb) concentrations were measured prefeed for the first 7 postnatal days. Infants were exclusively breastfed (BF), breastfed with formula milk supplementation (FS), or exclusively formula milk fed (FF). RESULTS: Within the SGA group, a measure of "thinness," the midarm circumference/head circumference ratio, was significantly correlated to the number of episodes of blood glucose < 2.00 mmol/L. Epoch (age at sampling) analysis in this group showed no difference in blood glucose levels across the different feeding groups but revealed a statistically significant greater kb concentration for infants who were exclusively breastfed. For SGA infants, the median peak kb concentration (peak kb) was significantly different for BF, FS, and FF groups. Multiple regression analysis for the SGA group demonstrated that peak kb concentration was negatively related to the volume of formula milk, independent of blood glucose levels and neonatal anthropometry. For LGA infants, low blood glucose levels were offset by kb concentrations equivalent to those observed in infants who were appropriate for gestational age. CONCLUSION: Neonatal ability to generate kb when blood glucose values are low depends more on successful breastfeeding than on size for gestational age or neonatal nutritional status. Routine blood glucose monitoring of LGA infants with no additional risk factors is not necessary. Routine formula milk supplementation for LGA and SGA infants should not be recommended.