Implementation of the INTERGROWTH-21st Project in the United States.

The North American site in the INTERGROWTH-21(st) Project was North Seattle, Washington State, USA. The majority of the data were collected from within Seattle City, which has approximately 12 300 births per year. The sample for the Newborn Cross-Sectional Study (NCSS) was drawn from two hospitals (Swedish Medical Center and the University of Washington) covering almost 80% of deliveries within the target population. The Fetal Growth Longitudinal Study (FGLS) sample was recruited from several antenatal clinics serving the University of Washington Medical Center and Providence Everett Medical Center. Special activities to encourage participation and raise awareness of the studies included furnishing the recruitment sites with fliers designed by the Project Coordinating Unit, and presenting the studies to clinical staff to encourage providers to refer appropriate patients. One of the major challenges at this site was the low recruitment rate in the early phase of the FGLS because of the high rates of smoking, maternal age >35 years and body mass index >30 years. This was remedied by the inclusion of other ancillary clinics, as well as increased advertising among the general public.

Implementation of the INTERGROWTH-21st Project in India.

The South Asian site in the INTERGROWTH-21(st) Project was the city of Nagpur, in Maharashtra State, India, with approximately 4500 births per year among the target population with middle to high socio-economic status. These deliveries are mainly concentrated in 20 small private hospitals, most of which are in the city centre. The sample for the Newborn Cross-Sectional Study (NCSS) was drawn from ten of these hospitals, covering 76% of the target low-risk pregnant population. The Fetal Growth Longitudinal Study (FGLS) sample was recruited from the largest of these institutions, Ketkar Hospital, as well as several ancillary antenatal care clinics. Special activities to encourage participation and raise awareness of the study at this site included translating patient information leaflets into local languages and securing local media interest. Among the unique challenges of the Indian site was the coordination of the large number of hospitals involved in NCSS, a task that required careful planning and organisation by the field teams.

Implementation of the INTERGROWTH-21st Project in the UK.

There are approximately 10,000 births per year in the county of Oxfordshire in the UK, which is one of the two European sites for the International Fetal and Newborn Growth Consortium for the 21(st) Century (INTERGROWTH-21(st) ) Project. The samples for both components of the project--the Fetal Growth Longitudinal Study (FGLS) and Newborn Cross-Sectional Study (NCSS)--were drawn from the John Radcliffe Hospital, a major university hospital with a large regional role that covers more than 75% of deliveries in the county. Special activities to encourage participation in this population included the formation of a research coalition to streamline recruitment in the Maternity Unit and the distribution of study information leaflets to women using the hospital's antenatal care service. This was a demanding project and several challenges were overcome to reach recruitment targets and to maintain high standards of data quality. Amongst the major challenges for FGLS at this study site was the level of ineligibility because of maternal age, smoking and body mass index (BMI) ≥ 30. The major challenge for the NCSS field teams was to ensure that all anthropometric data were collected before the early discharge of uncomplicated deliveries, often within 6 hours of birth. It is evident from our experience in implementing this project that, when large-scale clinical studies are meticulously planned and avoid major disruption to routine clinical care, they are well received by hospital staff and can contribute to the improvement of the overall standard of clinical care.