Can increased resistance to uterine artery flow be a risk factor for adverse neurodevelopmental outcomes in childhood? A prospective cohort study

A prospective cohort study was conducted to determine whether an increased uterine artery pulsatility index (UtA-PI) in the second trimester of pregnancy is a risk factor for neurodevelopmental outcomes in children 2-3 years of age. A group of pregnant women with a UtA-PI below the 90th percentile (P90) and a second group with a UtA-PI ≥ P90 in the second trimester were included in this study. The children of these women were evaluated during their second or third year of life using the Bayley III Screening Test. A total of 858 pregnancies with UtA-PI < P90 and 96 pregnancies with UtA-PI ≥ 90 were studied. The differences between the groups related to UtA-PI ≥ 90 were detected in relation to the variables of the Caucasian ethnicity, hypertension, newborn weight and stay in the intensive care unit after birth. However, adjusted neurodevelopmental outcomes did not differ between the groups: OR 0.53 (95% CI 0.27-1.04%). This study failed to demonstrate that the UtA-PI is a risk factor for adverse neurodevelopment in children.Impact statementWhat is already known on this subject? Early interventions in children at high risk for neurodevelopmental deficiency have proved to be beneficial. The complications associated with gestation and delivery negatively influence neurodevelopment. Several studies have shown that some adverse pregnancy outcomes such as preeclampsia, foetal growth restriction and foetal death can be predicted by increased resistance to flow in the uterine artery in the second trimester. However, there are no studies evaluating the association of the uterine artery with neurodevelopmental results.What do the results of this study add? This study concludes that neurodevelopment is influenced by multiple environmental and intrinsic factors and cannot be predicted by only one variable, such as the uterine artery blood flow. The brain has repair mechanisms to attenuate insults that occur during gestation and delivery.What are the implications of these findings for clinical practice and/or further research? This study was unable to demonstrate that blood flow in the uterine artery is a risk factor for neurodevelopment. Different, larger studies should be conducted by combining other factors with the uterine artery in an algorithm to allow the early identification of children at risk for neurodevelopmental impairment.

A global reference for caesarean section rates (C-Model): a multicountry cross-sectional study

Objective

To generate a global reference for caesarean section (CS) rates at health facilities.

Design

Cross‐sectional study.

Setting

Health facilities from 43 countries.

Population/Sample

Thirty eight thousand three hundred and twenty‐four women giving birth from 22 countries for model building and 10 045 875 women giving birth from 43 countries for model testing.

Methods

We hypothesised that mathematical models could determine the relationship between clinical‐obstetric characteristics and CS. These models generated probabilities of CS that could be compared with the observed CS rates. We devised a three‐step approach to generate the global benchmark of CS rates at health facilities: creation of a multi‐country reference population, building mathematical models, and testing these models.

Main outcome measures

Area under the ROC curves, diagnostic odds ratio, expected CS rate, observed CS rate.

Results

According to the different versions of the model, areas under the ROC curves suggested a good discriminatory capacity of C‐Model, with summary estimates ranging from 0.832 to 0.844. The C‐Model was able to generate expected CS rates adjusted for the case‐mix of the obstetric population. We have also prepared an e‐calculator to facilitate use of C‐Model (www.who.int/reproductivehealth/publications/maternal_perinatal_health/c-model/en/).

Conclusions

This article describes the development of a global reference for CS rates. Based on maternal characteristics, this tool was able to generate an individualised expected CS rate for health facilities or groups of health facilities. With C‐Model, obstetric teams, health system managers, health facilities, health insurance companies, and governments can produce a customised reference CS rate for assessing use (and overuse) of CS.

Tweetable abstract

The C‐Model provides a customized benchmark for caesarean section rates in health facilities and systems.

The C‐Model provides a customized benchmark for caesarean section rates in health facilities and systems.

Incidência de cesáreas segundo fonte de financiamento da assistência ao parto

OBJETIVO: Estudar os tipos de partos de acordo com a categoria de internação da paciente, bem como as indicações de cesarianas mais freqüentemente referidas. MÉTODOS: A partir dos dados de um sistema de informações hospitalares, foi feita uma análise retrospectiva dos partos ocorridos no município de Ribeirão Preto, São Paulo, Brasil, no período de 1986-1995. Foram estudados: tipo de parto, categoria de admissão e diagnósticos referidos. RESULTADOS: Ocorreram 86.120 partos no período estudado, sendo 5,4% na categoria privada, 28,7% na categoria de pré-pagamento e 65,9% no sistema público (Sistema Único de Saúde -- SUS), observando-se uma diminuição nas categorias privada e SUS e aumento na categoria de pré-pagamento. A percentagem de cesáreas aumentou de 68,3% para 81,8% na categoria privada e de 69,1% para 77,9% na categoria pré-pagamento e diminuiu de 38,7% para 32,1% na categoria SUS. As principais indicações cesarianas referidas foram o sofrimento fetal, cujas incidências foram 9,5%, 10,9% e 9,0%, respectivamente, nas categorias particular, pré-pagamento e SUS; e distócia céfalo-pélvica cujas taxas foram 5,8%, 6,5% e 3,9%, respectivamente, nas mesmas categorias mencionadas. CONCLUSÃO: A incidência de cesariana variou segundo a categoria de internação, observando-se um gradiente crescente à medida que se elevou o padrão social das gestantes, não havendo correspondência com o risco obstétrico.