The 2004 Birth Cohort started in order to continue the studies that have already been conducted in the follow-ups of the 1982 and the 1993 birth cohorts. Thus, with the new birth cohort, there would be a universe of 15 thousand participants, and it would allow a wider evaluation of the changes in the social and epidemiological health patterns.
The methodology used to form the 2004 Birth Cohort was similar to the process of the other ones. The cohort consists of all children born from the first to the last day of 2004, whose mothers lived in the urban area of Pelotas. However, the 2004 Birth Cohort also included the neonates whose mothers lived at Jardim América, a neighborhood from the neighbor city Capão do Leão. This change was necessary because of the first feature observed in this group: the low birth rate in relation to 1982 and 1993. Even with the addition of mothers from Capão do Leão, the 2004 Birth Cohort has 4.231 participants, more than a thousand less participants than the other birth cohorts.
In its first years, it was realized a perinatal study, a 3-month and a 12-month follow-ups. Simultaneously to the first follow-up, it was made a study about the child mortality and morbidity.
In the perinatal study, all participants’ mothers were interviewed in the first 24 hours after giving birth, at the five maternity hospitals of Pelotas. The questionnaires filled in by the mothers had biological, demographic, socioeconomic and assistance questions. The data about the neonates included information about their sex, the kind of pregnancy (singleton or twin pregnancy), gestational age, morbidity and perinatal mortality, and the kind of parturition. The neonates were weighted after their birth.
The 3-month and the 12-month follow-ups were made in the participants’ houses. The information collected were about the socioeconomic family situation, the mother’s mental health and habits, and features, habits and the baby’s development.
children were 6 years old in 72-month analysis, which started in October 2010 and did not occur in their houses, as the other ones. The fifth follow-up of the 2004 Birth Cohort inaugurated the new building of the Center of Epidemiological Research (CPE), which was exclusively built to receive the cohort's participants.
The place keeps its latest equipment for different kind of exams. The 2004 Birth Cohort used the DXA (Dual-energy X-ray Absorptiometry), which allows the evaluation of body composition, the BOD POD, which measures the body density, and the 3D Photonic Scanner, which creates a three-dimensional body image and takes measures as legs and arms’ length, circumferences, height, etc.
Besides those exams, in 72-month follow-up the researchers collected socioeconomic data, as well as data about schooling, eating habits, child development, among others.
The details about the 2004 Birth Cohort studies are presented in innumerous scientific articles, which have been written by CPE researchers, and by students of the Postgraduate Program in Epidemiology at the UFPel. You can read some of those papers that are available at open access journals.
The instruments and the questionnaire used in the main follow-up studies and analyses are available for the scientific community.
