Further evidence of psychological factors underlying choice of elective cesarean delivery (ECD) by primigravidae

Objective: Requests for elective cesarean delivery (ECD) have increased in Iran. While some sociodemographic and fear-related factors have been linked with this choice, psychological factors such as self-esteem, stress, and health beliefs are under-researched. Methods: A total of 342 primigravidae (mean age = 25 years) completed questionnaires covering psychological dimensions such as self-esteem, perceived stress, marital relationship quality, perceived social support, and relevant health-related beliefs. Results: Of the sample, 214 (62.6%) chose to undergo ECD rather than vaginal delivery (VD). This choice was associated with lower self-esteem, greater perceived stress, belief in higher susceptibility to problematic birth and barriers to an easy birth, along with lower perceived severity of ECD, fewer perceived benefits from VD, lower self-efficacy and a lower feeling of preparedness. No differences were found for marital relationship quality or perceived social support. Conclusions: The pattern suggests that various psychological factors such as self-esteem, self-efficacy, and perceived stress underpin the decision by primigravidae to have an ECD

External validation of prognostic models to predict stillbirth using the International Prediction of Pregnancy Complications (IPPIC) Network database: an individual participant data meta-analysis

Objective Stillbirth is a potentially preventable complication of pregnancy. Identifying women at high risk of stillbirth can guide decisions on the need for closer surveillance and timing of delivery in order to prevent fetal death. Prognostic models have been developed to predict the risk of stillbirth, but none has yet been validated externally. In this study, we externally validated published prediction models for stillbirth using individual participant data (IPD) meta-analysis to assess their predictive performance. Methods MEDLINE, EMBASE, DH-DATA and AMED databases were searched from inception to December 2020 to identify studies reporting stillbirth prediction models. Studies that developed or updated prediction models for stillbirth for use at any time during pregnancy were included. IPD from cohorts within the International Prediction of Pregnancy Complications (IPPIC) Network were used to validate externally the identified prediction models whose individual variables were available in the IPD. The risk of bias of the models and cohorts was assessed using the Prediction study Risk Of Bias ASsessment Tool (PROBAST). The discriminative performance of the models was evaluated using the C-statistic, and calibration was assessed using calibration plots, calibration slope and calibration-in-the-large. Performance measures were estimated separately in each cohort, as well as summarized across cohorts using random-effects meta-analysis. Clinical utility was assessed using net benefit. Results Seventeen studies reporting the development of 40 prognostic models for stillbirth were identified. None of the models had been previously validated externally, and the full model equation was reported for only one-fifth (20%, 8/40) of the models. External validation was possible for three of these models, using IPD from 19 cohorts (491 201 pregnant women) within the IPPIC Network database. Based on evaluation of the model development studies, all three models had an overall high risk of bias, according to PROBAST. In the IPD meta-analysis, the models had summary C-statistics ranging from 0.53 to 0.65 and summary calibration slopes ranging from 0.40 to 0.88, with risk predictions that were generally too extreme compared with the observed risks. The models had little to no clinical utility, as assessed by net benefit. However, there remained uncertainty in the performance of some models due to small available sample sizes. Conclusions The three validated stillbirth prediction models showed generally poor and uncertain predictive performance in new data, with limited evidence to support their clinical application. The findings suggest methodological shortcomings in their development, including overfitting. Further research is needed to further validate these and other models, identify stronger prognostic factors and develop more robust prediction models. (c) 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.Peer reviewe

Optimising the use of caesarean section: a generic formative research protocol for implementation preparation

BACKGROUND: Caesarean section rates are rising across all geographical regions. Very high rates for some groups of women co-occur with very low rates for others. Both extremes are associated with short and longer term harms. This is a major public health concern. Making the most effective use of caesarean section is a critical component of good quality, sustainable maternity care. In 2018, the World Health Organization published evidence-based recommendations on non-clinical interventions to reduce unnecessary caesarean section. The guideline identified critical research gaps and called for formative research to be conducted ahead of any interventional research to define locally relevant determinants of caesarean birth and factors that may affect implementation of multifaceted optimisation strategies. This generic formative research protocol is designed as a guide for contextual assessment and understanding for anyone planning to take action to optimise the use of caesarean section. METHODS: This formative protocol has three main components: (1) document review; (2) readiness assessment; and (3) primary qualitative research with women, healthcare providers and administrators. The document review and readiness assessment include tools for local mapping of policies, protocols, practices and organisation of care to describe and assess the service context ahead of implementation. The qualitative research is organized according to twelve identified interventions that may optimise use of caesarean section. Each intervention is designed as a "module" and includes a description of the intervention, supporting evidence, theory of change, and in-depth interview/focus group discussion guides. All study instruments are included in this protocol. DISCUSSION: This generic protocol is designed to underpin the formative stage of implementation research relating to optimal use of caesarean section. We encourage researchers, policy-makers and ministries of health to adapt and adopt this design to their context, and share their findings as a catalyst for rapid uptake of what works

Erratum: Corrigendum: Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution

International Chicken Genome Sequencing Consortium. The Original Article was published on 09 December 2004. Nature432, 695–716 (2004). In Table 5 of this Article, the last four values listed in the ‘Copy number’ column were incorrect. These should be: LTR elements, 30,000; DNA transposons, 20,000; simple repeats, 140,000; and satellites, 4,000. These errors do not affect any of the conclusions in our paper. Additional information. The online version of the original article can be found at 10.1038/nature0315

Correlation between symmetry breaker position and the preferences of conformationally constrained homopeptides: A molecular dynamics investigation

The conformational tendencies of Calpha,alpha-diethylglycine (Deg)-based peptides have been studied in solution using all atom molecular dynamics simulations. Specifically, the conformational effects of breaking the symmetry of the host Tfa-(Deg)5-OtBu (Tfa, trifluoroacetyl; OtBu, tert-butoxy) pentapeptide with punctual replacements at different sequence positions of one Deg residue by its corresponding guest chiral analogue, L-alpha-aminobutyric acid (L-Abu), have been examined by simulating the following peptides: Tfa-(Deg)5-OtBu, Tfa-(Deg)2-L-Abu-(Deg)2-OtBu, Tfa-(Deg)3-L-Abu-Deg-OtBu, and Tfa-(Deg)4-L-Abu-OtBu. Simulations show that only the Deg homopeptide is able to stabilize a 2.05 helix, even though a kinked arrangement with all the Deg residues adopting a fully-extended conformation was found to be stable when the L-Abu residue is introduced in the middle of the sequence. On the other hand, when the L-Abu residue is closer to the C-end of the sequence, the peptide chain prefers a partially folded 3(10)-helix. Additional simulations on Tfa-(Deg)3-L-Abu-(Deg)3-OtBu highlighted that, when the size of the Deg segments increases, their tendency to adopt a 2.05 helix predominates over the preferred folded conformation of L-Abu. The overall picture extracted after more than 300 ns of molecular dynamics simulation is that breaking the alpha-carbon symmetry of achiral C-alpha-tetrasubstituted amino acids is a promising strategy to build up polypeptides with modulated conformational tendencies

In reply to letter to the editor from S. Y. Chu, S. Y. Kim and J. Lau

Universidade Federal de São Paulo, Dept Emergency & Evidence Based Med, São Paulo, BrazilBrazilian Cochrane Ctr, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Obstet, São Paulo, BrazilWHO, Dept Reprod Hlth & Res, CH-1211 Geneva, SwitzerlandUniv Fed Pelotas, Dept Epidemiol, Pelotas, BrazilUniversidade Federal de São Paulo, Dept Emergency & Evidence Based Med, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Obstet, São Paulo, BrazilWeb of Scienc

What is the optimal rate of caesarean section at population level? A systematic review of ecologic studies

In 1985, WHO stated that there was no justification for caesarean section (CS) rates higher than 10-15% at population-level. While the CS rates worldwide have continued to increase in an unprecedented manner over the subsequent three decades, concern has been raised about the validity of the 1985 landmark statement. We conducted a systematic review to identify, critically appraise and synthesize the analyses of the ecologic association between CS rates and maternal, neonatal and infant outcomes. Four electronic databases were searched for ecologic studies published between 2000 and 2014 that analysed the possible association between CS rates and maternal, neonatal or infant mortality or morbidity. Two reviewers performed study selection, data extraction and quality assessment independently. We identified 11,832 unique citations and eight studies were included in the review. Seven studies correlated CS rates with maternal mortality, five with neonatal mortality, four with infant mortality, two with LBW and one with stillbirths. Except for one, all studies were cross-sectional in design and five were global analyses of national-level CS rates versus mortality outcomes. Although the overall quality of the studies was acceptable; only two studies controlled for socio-economic factors and none controlled for clinical or demographic characteristics of the population. In unadjusted analyses, authors found a strong inverse relationship between CS rates and the mortality outcomes so that maternal, neonatal and infant mortality decrease as CS rates increase up to a certain threshold. In the eight studies included in this review, this threshold was at CS rates between 9 and 16%. However, in the two studies that adjusted for socio-economic factors, this relationship was either weakened or disappeared after controlling for these confounders. CS rates above the threshold of 9-16% were not associated with decreases in mortality outcomes regardless of adjustments. Our findings could be interpreted to mean that at CS rates below this threshold, socio-economic development may be driving the ecologic association between CS rates and mortality. On the other hand, at rates higher than this threshold, there is no association between CS and mortality outcomes regardless of adjustment. The ecological association between CS rates and relevant morbidity outcomes needs to be evaluated before drawing more definite conclusions at population level

Socio-demographic factors of cesarean births in Nha Trang city, Vietnam: a community-based survey

Background: The cesarean section rate in Vietnam has been increasing especially in urban area. However, limited evidence identified regarding socio-demographic factors of the cesarean section birth. The objective of this study was to determine the current cesarean birth rate and the associated socio-demographic factors among mothers in Nha Trang city, south-central Vietnam. Methods: A community-based cross-sectional study was conducted between October and November in 2016 as part of a Streptococcus pneumoniae carriage survey conducted in 27 communes of Nha Trang city. From each commune, 120 mothers and their children less than 2 years old were randomly selected. Mothers were asked to answer standardized questions regarding socio-demographic information and mode of birth. Multivariate logistic regression was adopted to examine associations between socio-demographic variables and mode of birth. Results: Of 3148 participants, the number of cesarean births was 1396 (44.3 %). Older maternal age (? 30 years old), having another child going to school or kindergarten, monthly income more than 644 USD, gestational weeks at birth over 42 weeks, and low (< 2500 g) or high (? 3500 g) birth weight were associated with higher likelihood of cesarean births. Conclusion: The CS rate obtained in this study was more than twice of what is recommended by the World Health Organization, which is consistent with the previous nation-wide study in Viet Nam. Further monitoring is suggested to examine the non-medical reason for the increased CS rate