Peter von Dadelszen

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Verified

Peter verified their affiliation via an institutional email.

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• BMedSc, MBChB, DipObst (Otago), DPhil (Oxon), CertMFM, CertClinPharm (Toronto), FRANZCOG, FRCSC, FRCOG
• Professor at King's College London

Introduction: Nearly three quarters of stillbirths and neonatal deaths occur in infants born prematurely. The mothers of these children may be at increased risk of developing mental health difficulties as a result of their premature labour and/or subsequent loss. Methods: This systematic review was conducted to understand the psychological experie...

Preterm birth is a significant public health concern. In England, 8.1% of all births in 2023 were classified as premature. The psychological impact of preterm birth on parents has become of increasing interest to researchers. However, the long-term psychological impact on preterm babies, the effect prematurity has on wider family units, and the eff...

Background The COVID-19 pandemic resulted in major maternity service reconfigurations, particularly an increase in virtual antenatal care (vANC). We aimed to explore the relationship between vANC trajectories over time and pregnancy outcomes. Methods Pregnancy and birth outcome data were obtained pre-pandemic, during the pandemic with, and without...

Between 2020 and 2022 in the United Kingdom (UK), there were 45 maternal deaths from venous thromboembolism (VTE), out of more than 2 million maternities. This occurred despite extensive risk assessment and prescribing of low molecular weight heparin (LMWH) thromboprophylaxis, alongside clinicians' overestimate of risk and commitment to the cause....

Purpose The PREgnancy Care Integrating translational Science, Everywhere Network was established to investigate specific placental disorders (pregnancy hypertension, preterm birth, fetal growth restriction and stillbirth) in sub-Saharan Africa. We created a repository of clinical and social data with associated biological samples from pregnant and...

Background Pre‐eclampsia is a leading cause of maternal and perinatal morbidity and mortality. There are several determinants of individual pregnant women's risk of developing pre‐eclampsia, including biomarkers and ultrasound markers. Objective A conceptual framework to collate and summarise the extensive body of literature on biomarkers (includi...

(Abstracted from BJOG 2024;131:1673–1683) Fetal growth restriction (FGR) occurs when a fetus grows slower than expected for gestational age. Severe early-onset cases are associated with stillbirth, neonatal death, and developmental disorders.

Objectives: To evaluate whether term pre-eclampsia (PE) is reduced by screening for PE risk at 35 + 0-36 + 6 weeks' gestation and offering risk-based, planned early term birth. Study design: 'PREVENT-PE' is a multicentre, randomised trial (ISRCTN41632964). Inclusion: Singleton pregnancy, presentation for routine fetal ultrasound at 35 + 0-36 + 6 we...

Pregnant and lactating women in sub-Saharan Africa are vulnerable to micronutrient inadequacies, with risk of adverse pregnancy outcomes. Adequate intakes of diverse foods are associated with better micronutrient status and recommended by the World Health Organization as part of healthy eating counselling during antenatal care. However, our underst...

Community engagement (CE) has been recommended as an important ethical consideration for health research to enhance informed consent and exchange knowledge between researchers and community members. The purpose of this paper is to describe how CE was developed and delivered for the PRECISE prospective pregnancy cohort study in Kenya. PRECISE enroll...

Background Risk factors for the placental disorders of pregnancy (pre‐eclampsia, fetal growth restriction, preterm birth, and stillbirth) are complex, frequently involving the interplay between clinical factors and wider social and environmental determinants of health. Biomarkers modulate the maternal and fetal responses to biological processes tha...

Background Existing reviews of pre‐eclampsia determinants have focused on clinical and genetic risk factors. Objective To evaluate social determinants for pre‐eclampsia prevention. Search Strategy Systematic searches were conducted from relevant electronic databases from inception of each database to 30th December 2024. Selection Criteria Review...

Objective The objective of this study is to examine the association between dietary calcium intake (Ca) and pre‐eclampsia (PE). Design Cohort study. Setting Inner‐city hospital. Population A total of 2838 women with singleton pregnancies at 35⁺⁰–36⁺⁶ weeks' gestation, including 96 (3.4%) who subsequently developed PE. Methods Online 24‐h dietar...

Background Preeclampsia is a potentially life-threatening pregnancy complication. Among women whose pregnancies are complicated by preeclampsia, the Preeclampsia Integrated Estimate of RiSk (PIERS) models (i.e., the PIERS Machine Learning [PIERS-ML] model, and the logistic regression-based fullPIERS model) accurately identify individuals at greates...

Background In 2017, the American College of Cardiology and American Heart Association (ACC/AHA) lowered blood pressure (BP) thresholds to define hypertension in adults outside pregnancy. If used in pregnancy, these lower thresholds may identify women at increased risk of adverse outcomes, which would be particularly useful to risk-stratify nullipar...

Objective: Globally, one in four pregnant women is classified as overweight or obese, based on their prepregnancy body mass index (BMI). Obese pregnant women are at increased risk of adverse pregnancy outcomes and long-term cardiovascular disease that occurs earlier in life. This study aimed to assess maternal hemodynamic and vascular parameters a...

Maternity care is a core service provision of any healthcare system, delivering care for women and birthing people, and their wider family units. During the SARS-CoV-2 pandemic, much of maternity care service provision was reconfigured with the aim of continuing care provision which could not otherwise be re-scheduled or delayed, but in-line with i...

Problem and background During the COVID-19 pandemic, there was substantial reconfiguration of maternity care services, affecting both users and healthcare providers (HCPs), in the United Kingdom (UK) and globally. Aim To further our understanding of the impact of maternity service reconfigurations in the UK, from the perspective of maternity HCPs....

Background : During the COVID-19 pandemic, maternity care reconfigurations disrupted in-person care, which shifted towards virtual care and self-monitoring. We assessed the impact of these changes on healthcare costs. Methods : Data from October 2018 to April 2023 were used from the population-based early-LIfe data cross-LInkage in Research-Born-in...

Background Chronic or gestational hypertension complicates approximately 7% of pregnancies, half of which reach 37 weeks’ gestation. Early term birth (at 37 to 38 weeks) may reduce maternal complications, cesareans, stillbirths, and costs but may increase neonatal morbidity. In the WILL Trial (When to Induce Labour to Limit risk in pregnancy hypert...

( BJOG. 2024;131:46–62. DOI: 10.1111/1471-0528.17320) Preeclampsia affects 2% to 4% of pregnancies globally, with a rising incidence linked to increasing maternal age and body mass. This hypertensive disorder poses significant risks to both maternal and fetal health, making it a key focus of prenatal care through blood pressure and proteinuria scre...

Background : Due to the COVID-19 pandemic, maternity care reconfigurations disrupted in-person care, which shifted towards virtual care and self-monitoring. We assessed the impact of these changes on maternity service provision costs. Methods : Data from October 2018 to April 2023 were used from the population-based early-LIfe data cross-LInkage in...

Objectives : Preeclampsia (PE) occurs most commonly at term, and currently, there is no effective strategy to prevent it. The PE prevention by timed birth at term trial (PREVENT- PE) with embedded economic evaluation aims to provide cost-effectiveness evidence on whether screening for PE risk at 35+0–36+6 weeks’ gestation and offering women risk-ba...

Background Training health workers might facilitate respectful maternity care (RMC); however, the content and design of RMC training remain unclear. Objective To explore the content and design of RMC training packages for health workers in sub‐Saharan Africa. Search Strategy MEDLINE, EMBASE, CINAHL Complete, Web of Science Core Collections, SCOPU...

Objectives: To evaluate whether term pre-eclampsia (PE) can be reduced by screening for PE risk at 35⁺⁰–36⁺⁶ weeks’ gestation and offering women risk-based, planned term birth. Study design: ‘PREVENT-PE’ is a pragmatic, multicentre, randomised trial. Inclusion: singleton pregnancy, presentation for routine fetal ultrasound at 35⁺⁰-36⁺⁶ weeks’ gesta...

Background Severe early-onset intrauterine growth restriction is associated with stillbirth, neonatal death and neurodevelopmental impairment. There is no treatment for intrauterine growth restriction with timely delivery being the only management option. Placentas from intrauterine growth restriction pregnancies often show failure to remodel mater...

Maternal vaccination during pregnancy, in general and against COVID-19 infection, offers protection to both mother and baby, but uptake remains suboptimal. This study aimed to explore the perceptions regarding COVID-19 vaccination in pregnancy, particularly for marginalised populations and those living with social or medical complexity. A total of...

Background There is an emerging need to systematically investigate the causes for the increased cesarean section rates in Greece and undertake interventions so as to substantially reduce its rates. To this end, the ability of the participating Greek obstetricians to follow evidence-based guidelines and respond to other educational and behavioral in...

Background Women who suffer an early pregnancy loss require specific clinical care, aftercare, and ongoing support. In the UK, the clinical management of early pregnancy complications, including loss is provided mainly through specialist Early Pregnancy Assessment Units. The COVID-19 pandemic fundamentally changed the way in which maternity and gyn...

Introduction Healthcare services for pregnant and postpartum (‘perinatal’) women were reconfigured significantly at the advent and for the duration of the SARS-CoV-2 pandemic, and despite the United Kingdom announcing ‘Freedom Day’ on 19 July 2021 (whereafter all legal lockdown-related restrictions were lifted), restrictions to maternity (antenatal...

Background Over 250 million children are not reaching their developmental potential globally. The impact of prenatal factors and their interplay with postnatal environmental factors on child neurodevelopment, is still unclear—particularly in low- and middle-income settings. This study aims to understand the impact of pregnancy complications as well...

Maternity care is a core service provision of any healthcare system, delivering care for women and birthing people, and their wider family units. During the SARS-CoV-2 pandemic, much of maternity care service provision was reconfigured with the aim of continuing care provision which could not otherwise be re-scheduled or delayed, but in-line with i...

Objective Severe early‐onset fetal growth restriction (FGR) causes stillbirth, neonatal death and neurodevelopmental impairment. Poor maternal spiral artery remodelling maintains vasoactive responsiveness but is susceptible to treatment with sildenafil, a phosphodiesterase type 5 (PDE5) inhibitor, which may improve perinatal outcomes. Design Super...

Introduction The burden of severe maternal morbidity is highest in sub-Saharan Africa, and its relative contribution to maternal (ill) health may increase as maternal mortality continues to fall. Women’s perspective of their long-term recovery following severe morbidity beyond the standard 42-day postpartum period remains largely unexplored. Metho...

Background: Existing reviews of pre-eclampsia determinants have focused on clinical and genetic risk factors. Objective: To evaluate social determinants for pre-eclampsia prevention. Search strategy: Systematic searches were conducted on relevant electronic databases to 31 July 2023. Selection criteria: Reviews and large cohort studies (≥1,000 part...

Background Climate change, particularly global warming, is amongst the greatest threats to human health. While short-term effects of heat exposure in pregnancy, such as preterm birth, are well documented, long-term effects have received less attention. This review aims to systematically assess evidence on the long-term impacts on the foetus of heat...

Background Maternity care services in the United Kingdom have undergone drastic changes due to pandemic-related restrictions. Prior research has shown maternity care during the pandemic was negatively experienced by women and led to poor physical and mental health outcomes in pregnancy. A synthesis is required of published research on women’s exper...

BACKGROUND In high-resource settings, biomarkers of angiogenic balance, such as the soluble fms-like tyrosine kinase-1 (sFlt1)/placental growth factor (PlGF) ratio, have been studied extensively to aid in evaluation of patients with suspected preeclampsia (PE), and have been incorporated into the 2021 International Society for the Study of Hyperten...

COVID-19 vaccination rates are lower in women of reproductive age (WRA), including pregnant/postpartum women, despite their poorer COVID-19-related outcomes. We evaluated the vaccination experiences of 3568 U.K. WRA, including 1983 women (55.6%) experiencing a pandemic pregnancy, recruited through the ZOE COVID Symptom Study app. Two staggered onli...

Background PRECISE-DYAD is an observational cohort study of mother-child dyads running in urban and rural communities in The Gambia and Kenya. The cohort is being followed for two years and includes uncomplicated pregnancies and those that suffered pregnancy hypertension, fetal growth restriction, preterm birth, and/or stillbirth. Methods The PREC...

Background Affecting 2–4% of pregnancies, pre-eclampsia is a leading cause of maternal death and morbidity worldwide. Using routinely available data, we aimed to develop and validate a novel machine learning-based and clinical setting-responsive time-of-disease model to rule out and rule in adverse maternal outcomes in women presenting with pre-ecl...

Background Long‐term (visit‐to‐visit) blood pressure variability (BPV) and heart rate variability (HRV) outside pregnancy are associated with adverse cardiovascular outcomes. Given the limitations of relying solely on blood pressure level to identify pregnancies at risk, long‐term (visit‐to‐visit) BPV or HRV may provide additional diagnostic/progno...

( Am J Obstet Gynecol . 2023;228(4):418–429.e34) Many risk factors contribute to adverse outcomes in pregnancy related to elevated blood pressure. High blood pressure or hypertension, has also been shown to be connected to poor outcomes outside of pregnancy, and clinical guidelines have recently changed to reflect stage 1 and stage 2 hypertension r...

Objective To investigate the validity of the conclusion from Cochrane reviews and meta‐analyses that treatment with calcium supplementation during pregnancy reduces the risk for pre‐eclampsia by 55%, which has been influential in international guidelines and future research. Design Sensitivity analysis of data from Cochrane reviews of trials evalu...

Differences in the cervicovaginal microbiota are associated with spontaneous preterm birth (sPTB), a significant cause of infant morbidity and mortality. Although establishing a direct causal link between cervicovaginal microbiota and sPTB remains challenging, recent advancements in sequencing technologies have facilitated the identification of mic...

Background Seroprevalence studies are an alternative approach to estimating the extent of transmission of SARS-CoV-2 and the evolution of the pandemic in different geographical settings. We aimed to determine the SARS-CoV-2 seroprevalence from March 2020 to March 2022 in a rural and urban setting in Kilifi County, Kenya. Methods We obtained repres...

Objective To examine the association with adverse pregnancy outcomes of: (1) American College of Cardiology/American Heart Association blood pressure (BP) thresholds, and (2) visit‐to‐visit BP variability (BPV), adjusted for BP level. Design An observational study. Setting Analysis of data from the population‐based UK Southampton Women's Survey (...

Objective To determine the impact of implementing emergency care pathway(s) for screening, diagnosing and managing women with gestational diabetes (GDM) during COVID‐19. Design Retrospective multicentre cohort. Setting Nine National Health Service (NHS) Hospital Trusts/Health boards in England and Scotland. Population 4915 women with GDM pre‐pan...

Background: Over 250 million children are not reaching their developmental potential globally. The impact of prenatal factors then influenced by postnatal environmental factors on child neurodevelopment, is still unclear—particularly in low- and middle-income settings. This study aims to understand the impact of placental complications as well as e...

BACKGROUND Cardiovascular disease is the leading cause of mortality in women. Pregnancy is an ideal period to implement cardiovascular prevention strategies as women seek medical help. We aimed to develop a predictive model to identify women at increased risk for chronic hypertension (CH) based on information collected in the index pregnancy. METH...

Objective To determine whether serum placental growth factor (PlGF) at 19–23 weeks of gestation can improve the identification of risk for adverse outcomes. Design Prospective observational cohort study. Setting Two English maternity units. Population Unselected singleton pregnancies attending routine ultrasound at 19–23 weeks of gestation. Met...

Background: The Three Delays Framework was instrumental in the reduction of maternal mortality leading up to, and during the Millennium Development Goals. However, this paper suggests the original framework might be reconsidered, now that most mothers give birth in facilities, the quality and continuity of the clinical care is of growing importanc...

Background There is an emerging need to systematically investigate the causes for the increased cesarean section rates in Greece and undertake interventions so as to substantially reduce its rates. To this end, the ability of the participating Greek obstetricians to follow evidence-based guidelines and respond to other educational and behavioral in...

( BJOG . 2022;129:1833–1843) Pre-eclampsia effects 2% to 5% of pregnancies. Health disparities are apparent with 99% of maternal pre-eclamptic deaths occurring in low- and middle-income countries (total deaths are between 30,000 and over 500,000 annually). A daily dose of aspirin (150 mg) has been shown to prevent 60% of preterm (<37 wk of gestatio...

Objectives: SARS-CoV-2 transmission in Sub-Saharan Africa has probably been underestimated. Population-based seroprevalence studies are needed to determine the extent of transmission in the continent. Methods: Blood samples from a cohort of Gambian pregnant women were tested for SARS-CoV-2 total receptor binding domain (RBD) IgM/IgG before (Pre-...

Objective To compare the causes of death for women who died during pregnancy and within the first 42 days postpartum with those of women who died between >42 days and within 1 year postpartum. Design Open population cohort (Health and Demographic Surveillance Systems). Setting Ten Health and Demographic Surveillance Systems (HDSS) in The Gambia,...

Background: Fetal growth restriction (FGR) is a condition of poor growth of the fetus in utero. One of the causes of FGR is placental insufficiency. Severe early-onset FGR at < 32 weeks of gestation occurs in an estimated 0.4% of pregnancies. This extreme phenotype is associated with a high risk of fetal death, neonatal mortality, and neonatal mor...

Objective: To compare the performance at 35+0 to 36+6 weeks' gestation of screening for delivery with pre-eclampsia (PE) at various time points, using one of three approaches: placental growth factor (PlGF) concentration, the soluble fms-like tyrosine kinase-1 (sFLT-1) to PlGF concentration ratio, or the competing risks model, which combines mater...

Objectives SARS-CoV-2 transmission in Sub-Saharan Africa has probably been underestimated. Population-based seroprevalence studies are needed to determine the extent of transmission in the continent. Methods Blood samples from a cohort of Gambian pregnant women were tested for SARS-CoV-2 total IgM/IgG before (Pre-pandemic1: October-December 2019 an...