Studies - 1993 Cohort

The 5.249 participants of the 1993 Birth Cohort were very important for the development of health research in Brazil. With the willingness of all these people, the scientific community gathered important information about different phases of the participants' lives, from their habits and their mothers' health during pregnancy, their development as children and their first adolescence features, to their health as young adults.

CPE is very grateful to the collaboration of all mothers who, a little after their childbirth, accepted to answer a lot of questions to the researchers, and allowed that their newborns were tested for measuring and weight analyses.

More than the collaboration that those mothers gave to the researchers at the hospital, they also gave their addresses and, with no immediate benefit, they have received the researchers a lot of times during many years in order that the researchers could follow their children's development.

All the available time provided by the mothers and by the own participants, and all the work that the researchers had to find those almost six thousand families along 30 years, are nowadays worth for the scientific knowledge that is available for the population.

Check out some data from the 1993 Birth Cohort


  • 5.249 births of alive babies.

Mother's age:

  • Mothers were from 13 to 48 years old.
  • 17,4% of all mothers were less than 20 years old.
    The maternal age was proportional to the family income, so that mothers with a higher family income were 4,3 years older than poorer mothers.

Babies Sex:

  • 49,7% of female neonates.
  • 50,3% of male neonates.


  • 30,5% of the mothers had a cesarean.
    Cesarean is a medical operation in which an opening is cut in a woman's body to take out the baby when the natural childbirth is not possible or safe.


  • 55,6% of the richer women had cesarean.
    It was observed that the high-risk women had less medical attention and care during their pregnancy and parturition than low-risk women.

Birth weight:

  • According to the World Health Organization (WHO), the birth weight is the most important factor for the child survival. Low birth weight babies (less than 5,5 pounds at birth) have more chances of getting sick or dying than babies with an adequate birth weight. Of the 5,249 births, there were 510 low birth weight babies.


  • 97% of the children were breastfed.
  • 30% of the babies were breastfed at the age of 6 months.
    It is known that non-breastfed babies have 30% more chances of dying in their first year life. The World Health Organization (WHO) recommends that children are breastfed until they are, at least, 6 months old. The breastfeeding may continue until they are 2 years old.


  • 33,4% of all mothers have smoked during their pregnancy.
    Smoking mothers' babies had a low birth weight rate bigger than non-smoking mothers' babies. It is known that low birth weight may cause the death of newborns.


  • Of the 5.249 births, 111 babies have died in their first year of life.
    Child mortality was 6,6 times bigger among the poorer than the richer participants. It was found that the highest risk of death occurs until the children are a year old. Owing to this, attention to children' health during this period must be reinforced by parents and doctors.

Update your information

If you are part of the researched 1993 Birth Cohort group, please update your information in order that we may find you for the next research stage.



If you have doubts about any research stage, please, contact us. We would be glad to help you.

Nome: Deise Veleda Modesto

Fone: (53) 3284-1321 | Ramais 362

Email: coorte1993@gmail.com


Epidemiology Postgraduate Program- Centre of Epidemiological Research