Individual Study / EST 2007-2008

EST 2007-2008 - Very low gestational age infants born in Estonia in 2007-2008

Networks -
Datasets -
Variables -

The aims of the conducted studies were to describe short-term and long-term outcome and health costs for very preterm (VPT) infants in Estonia, to identify risk factors for adverse outcome, and to benchmark the quality of perinatal services in the country.

A nationwide prospective cohort study comprised 360 live-born VPT infants born in Estonia in 2007–2008. Perinatal data were collected to the specially designed neonatal register. A historical cohort of 264 VPT infants born alive in 2002–2003 was selected for analysis of changes in the outcome until discharge. A sub-cohort of all 155 surviving VPT infants born in 2007 was followed up at 2 years of age and compared with a matched full-term control group. The subcohort underwent physical, neurological, and developmental assessment. Acute respiratory morbidity was identified by parental interviews and hospital database.

At 5 years of age, a sub-cohort of 55 surviving infants born in 2007-2008 at <29 weeks of gestation with a birthweight of <1000g, was followed up and compared with a full-term control group. The aims of the study were to measure long-term outcome for extremely preterm infants in Estonia, in comparison with historical group born in 2002-2003. The infants underwent physical, neurological, and developmental assessment. Some cardiovascular characteristics and blood biomarkers were measured in the subgroups. Health care cost data were driven from the database of the national Foundation of care for all very low gestational age children born in 2002-2003 and 2007-2008 from birth until 5 years of age and compared with term control cohort born in 2007.


Investigators Contacts
  • Heili Varendi
    University of Tartu
  • Liis Toome
    University of Tartu


EST 2007-2008
Start Year
End Year
Follow Up Is Ongoing
Year of Most Recent Data Collection
New Data Collection planned?
University of Tartu
Follow Up


Access to external researchers or third parties provided or foreseen.

Data (questionnaire-derived, measured...)
Other access

Study Design

Study design
Number of Data Collection Events
Number of very preterm (VPT) and/or very low birthweight (VLBW) births included in cohort (live & still births)
Supplementary information about number of participants
n= 187 for 2year follow up criteria / n= 56 for 5 yr For health care cost calculations 0-5 years: 264 liveborn from 2002-2003; 360 liveborn from 2007-2008; 153 term controls born in 2007.
Follow Up

Marker Paper

Toome L, Varendi H, Männamaa M, Vals MA, Tänavsuu T, Kolk A. Follow-up study of 2-year-olds born at very low gestational age in Estonia. Acta Paediatr 2013;102(3):300–7.

PUBMED 23176138



Population based cohort - all live born very preterm infants born in 2007-2008 in maternity units within Estonia who were registered in Estonian Medical Birth register.
Selection Criteria
  • Estonia
Geographical Area
All of Estonia
VPT/VLBW Group Inclusion Criteria
For 2 year follow up: all live births at <32 completed weeks of gestation, born in 2007.
For 5 year follow up: live births at <29 completed weeks of gestation, <1000g, born in 2007-2008.
Control Group Inclusion Criteria
Term healthy infant matched with the study group by sex, age and birth hospital.
VPT/VLBW Group Exclusion Criteria
Control Group Exclusion Criteria
Illness and intensive care requirement within 1st week of life.
Supplementary Information
Inclusion criteria are different for 2 year and 5 year follow up, including the range of birth years.
Data Collection Events
# Name Description Start End
0 Perinatal Assessment All live births at <32 GW in Estonia in 2007-2008 were recorded prospectively in a national neonatal research register. The register included 68 variables that were related to pregnancy risk ... 2007 2008
1 2 Year Follow Up Children underwent a clinical assessment by a pediatrician to examine physical, ophthalmological and auditory health. A neurological examination was undertaken by a child neurologist using the ... 2009 2010
2 5 Year Follow Up At 5 years of age, a physical clinical assessment was carried out. Developmental and neurological outcomes were assessed using the Reynell Developmental Language Scales Third Edition (RDLS-III), ... 2012 2014