Articles

Standardisation of crown-rump length measurement

Correct estimation of gestational age is essential for any study of ultrasound biometry and for everyday clinical practice. However, inconsistency in pregnancy dating may occur through differences in measurement methods or errors during measurement. This paper describes the standardised crown-rump length (CRL) measurement methodology and interpretation used across study sites in the INTERGROWTH-21^st Project. These methods should minimise potential systematic errors in dating associated with pooling data drom different health institutions, and represent a model for standardising CRL measurement in future studies. http://onlinelibrary.wiley.com/doi/10.1111/1471-0528.12056/abstract

Standardisation and quality control of ultrasound measurements taken in the INTERGROWTH-21st Project

Meticulous standardisation and ongoing monitoring of adherence to measurement protocols during data collection are essential to ensure consistency and to minimise systematic error in multicentre studies. Strict ultrasound fetal biometric measurement protocols are used in the INTERGROWTH-21^st Project so that data of the highest quality from different centres can be compared and potentially pooled. A central Ultrasound Quality Unit (USQU) has been set up to oversee this standardisation, training and quality control process. This paper describes the procedures used, which can form a model for research settings involving ultrasound measurements.

Ultrasound methodology used to construct the fetal growth standards in the INTERGROWTH-21st Project

A unified protocol is essential to ensure that fetal ultrasound measurements taken in multicentre research studies are accurate and reproducible. This paper describes the methodology used to take two-dimensional, ultrasound measurements in the longitudinal, fetal growth component of the INTERGROWTH-21^st Project. These standardised methods should minimise the systematic errors associated with pooling data from different sites. They represent a model for carrying out similar research studies in the future. http://onlinelibrary.wiley.com/doi/10.1111/1471-0528.12313/abstract

The objectives, design and implementation of the INTERGROWTH-21st Project

This paper outlines the objectives, design and implementation of the INTERGROWTH-21^st Project, a multicentre, multiethnic, population-based project conducted in eight geographical areas (Brazil, China, India, Italy, Kenya, Oman, UK and USA), with technical support from four global specialised units, to study growth, health and nutrition from pregnancy to early infancy. It aims to produce prescriptive growth standards, which conceptually extend the World Health Organization (WHO) Multicentre Growth Reference Study (MGRS) to cover fetal and newborn life. http://onlinelibrary.wiley.com/doi/10.1111/1471-0528.12047/abstract

Conceptual basis for prescriptive growth standards from conception to early childhood: present and future

Healthy growth in utero and after birth is fundamental for lifelong health and wellbeing. Current fetal growth charts in use are not true standards, since they are based on cross-sectional measurements of attained size under conditions that do not accurately reflect normal growth. The development of prescriptive intrauterine and newborn growth standards derived from the INTERGROWTH-21^st Project provides the data that will allow us for the first time to establish what 'normal' fetal growth is. http://onlinelibrary.wiley.com/doi/10.1111/1471-0528.12057/abstract

Introduction to INTERGROWTH-21st Methodology

Zulfiqar Bhutta, Chair of the INTERGROWTH-21^st Steering Committee, introduces the rationale for the INTERGROWTH-21^st Project. http://onlinelibrary.wiley.com/doi/10.1111/1471-0528.12032/abstract

Preface to INTERGROWTH-21st Methodology

Professor Sir Sabaratnam Arulkumaran, President of FIGO, introduces the methods of the INTERGROWTH-21^st Project. http://onlinelibrary.wiley.com/doi/10.1111/1471-0528.12314/abstract

The preterm birth syndrome: a prototype phenotypic classification

Preterm birth is a syndrome with many causes and phenotypes. We propose a classification system that is based on clinical phenotypes that are defined by >1 characteristics of the mother, the fetus, the placenta, the signs of parturition, and the pathway to delivery. Risk factors and mode of delivery are not included. There are 5 components in a preterm birth phenotype:

1. Maternal conditions that are present before presentation for delivery,
2. Fetal conditions that are present before presentation for delivery,
3. Placental pathologic conditions,
4. Signs of the initiation of parturition, and,
5. The pathway to delivery

Challenges in defining and classifying the preterm birth syndrome

In 2009, the Global Alliance to Prevent Prematurity and Stillbirth Conference charged the authors to propose a new comprehensive, consistent, and uniform classification system for preterm birth. This first article reviews issues related to measurement of gestational age, clinical vs etiologic phenotypes, inclusion vs exclusion of multifetal and stillborn infants, and separation vs combination of pathways to preterm birth. http://www.ncbi.nlm.nih.gov/pubmed/22118964

Novel biomarkers for the prediction of the spontaneous preterm birth phenotype: a systematic review and meta-analysis

Being able to predict preterm birth is important, as it may allow a high-risk population to be selected for future interventional studies and help in understanding the pathways that lead to preterm birth. This paper investigates the accuracy of novel biomarkers to predict spontaneous preterm birth in women with singleton pregnancies and no symptoms of preterm labour. http://www.ncbi.nlm.nih.gov/pubmed/21401853  

Systematic review of methodology used in ultrasound studies aimed at creating charts of fetal size

Reliable ultrasound charts are necessary for the prenatal assessment of fetal size, yet there is a wide variation of methodologies for the creation of such charts. This paper evaluates the methodological quality of studies of fetal biometry using a set of predefined quality criteria of study design, statistical analysis and reporting methods. Eighty-three studies met the inclusion criteria, and although multiple regression analysis shows that quality of studies has improved over time, there is considerable heterogeneity in study methodology still observed today. Standardisation of methodologies is necessary in order to make correct interpretations and comparisons between different charts. A checklist of recommended methodologies in proposed. http://www.ncbi.nlm.nih.gov/pubmed/22882780

Standardization of fetal ultrasound biometry measurements: improving the quality and consistency of measurements

The objective of this paper was to assess whether a standardization exercise prior to commencing a fetal growth study involving multiple sonographers can reduce interobserver variation. http://www.ncbi.nlm.nih.gov/pubmed/22411446

Malaria in Pregnancy

Effects of postnatal interventions for the reduction of vertical HIV transmission on infant growth and non-HIV infections: a systematic review

Rates and determinants of seasonal influenza vaccination in pregnancy and association with neonatal outcomes

There is growing evidence that seasonal influenza vaccination in pregnancy has benefits for mother and baby. The authors in this paper determined influenza vaccination rates among pregnant women during the 2 nonpandemic influenza seasons following the 2009 H1N1 pandemic, explored maternal factors as predictors of influenza vaccination status and evaluated the association between maternal influenza vaccination and neonatal outcomes. This study and others have shown an association between maternal influenza vaccination and improved neonatal outcomes, which supports stronger initiatives to promote vaccination during pregnancy.

Fetal Growth and Risk of Stillbirth: A Population-Based Case–Control Study

Stillbirth is strongly related to impaired fetal growth. However, the relationship between fetal growth and stillbirth is difficult to determine because of uncertainty in the timing of death and confounding characteristics affecting normal fetal growth. The study authors conducted a population-based case–control study of all stillbirths and a representative sample of live births in 59 hospitals in five geographic areas in the US. The study found that stillbirth is associated with both growth restriction and excessive fetal growth. These findings suggest that, contrary to current practices and recommendations, stillbirth prevention strategies should focus on both severe SGA and severe LGA pregnancies.

INTERGROWTH-21st Study Protocol

This study protocol descibes the the objectives, design and implementation of the Fetal Growth Longitudinal Study (FGLS), the Preterm Postnatal Followup Study (PPFS), and the Newborn Cross Sectional Study (NCSS). Data from these studies inform new, international fetal and newborn growth standards and a package of accompanying resources, including a new international equation for estimating gestational age through ultrasound. http://www.medscinet.net/Intergrowth/patientinfodocs/Intergrowth%20Protocol%20Sept%202009.pdf

Fetal Growth Longitudinal Study Operation Manual

This operation manual was used to implement the Fetal Growth Longitudinal Study (FGLS), which involved screening healthy women between 9 and 14 weeks gestation at the time of their early antenatal visit, and followed-up with standard clinical and 2D ultrasound examinations every 5 weeks, i.e. up to six times during a term pregnancy. The results of the FGLS inform new, international fetal and newborn growth standards and a package of supportive tools, guidelines and resources, including a new international equation for estimating gestational age through ultrasound. http://www.medscinet.net/Intergrowth/patientinfodocs/FGLS%20Manual%2015-09.pdf

Pregnancy and Delivery Form Instructions

This resource was used to train health professionals on how to record key data on pregnancies and deliveries for women participating in the Fetal Growth Longitudinal Study (FGLS) and Newborn Cross Sectional Study (NCSS). http://www.medscinet.net/Intergrowth/patientinfodocs/Pregnancy%20and%20Delivery%20Form%20Instructions.pdf

Basic Neonatal Care Manual

The INTERGROWTH-21^st Project used this manual to standardize definitions, treatment and management recommendations of neonatal morbidities.  http://www.medscinet.net/Intergrowth/patientinfodocs/Neonatal%20Manual%20Final.pdf