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Double risk Pregnancy

Marijuana harms the neurological development of newly born children

eduardo cesarIn an attempt to discover the consequences of marijuana used during pregnancy, a team of neonatologists, psychologists and psychiatrists from the Federal University of São Paulo (UNIFESP) investigated how the drug interferes in the neurological development of the fetus. The analysis of babies whose mothers consumed marijuana during the final three months of their pregnancy showed that in their first days of life, they were more stressed, less sensitive to external stimuli, cried more often and were more difficult to calm down in their crying crises than babies who had not been exposed to the drug. “Marijuana is the most consumed illicit drug in the world and its effects are the least studied”, says the study’s coordinator Ronaldo Laranjeira, from UNIFESP’s Psychiatry Department.

In order to reach this conclusion, the researchers evaluated the motor coordination, reflexes, muscular tonus and looked for signs of stress in 561 children with healthy adolescent mothers who were born at the Mário de Moraes Altenfelder Silva Hospital, in the northern zone of the of the city of São Paulo, between June 2001 and November 2002. The doctorate thesis of the pediatrician Marina Moraes Barros was concentrated on the study of babies with weight appropriate for a pregnancy age of 37 to 42 weeks who had not confronted any difficulty during the birth and whose mothers did not consume any other type of drug during the pregnancy. By way of the analysis of the adolescent mother’s thread of hair, the group detected that 26 of them had consumed marihuana during the final months of their pregnancy. The test was confirmed with the study of the first feces of each child, where residues of the drug were also found.

During the examinations, the babies who had had contact with marijuana showed themselves to be more restless, distracted and stressed. The researchers observed that they had disturbed sleep and more difficulty in awakening. With them, those tremors and brusque movements, very common among newly born, appeared with greater frequency.

Among the tests to evaluate the children’s attention, the researchers observed each child’s ability to accompany, with their eyes, the motion of a red ball moved in front of their face. Some of those who were exposed to marijuana hardly looked at the ball and the majority of them showed little interest. The scientists made use of other objects such as a rattle and a whistle, to test the reaction to visual and sonorous stimuli and concluded that these children were more inattentive. “This altered behavior during the first 72 hours of life means  that problems could exist in the formation of the baby’s brain”, interprets Ruth Guinsburg, from UNIFESP’s Pediatric Department, who coordinated the clinical research of the newly born. According to her, it is probable that the consumption of marijuana by the mother alters in the baby the communication between the neurons, triggered by the neurotransmitter dopamine and associated to the control of sensations such as excitement  and irritability.

However, these 26 newly born babies are not condemned to any type of neurological deficiency. The development of the brain does not depend only upon biological factors, but also the environment and the manner in which these babies are brought up. Small details such as attention, care and the availability of the mother and other family members to be always present, stimulating the baby’s perception through games and affection, are decisive for its formation. Knowing this, the researchers decided to trace out a social, economic and psychological profile of those adolescent mothers, in order to have an idea of the environment in which they will bring up their child and the chances of obtaining a healthy development. The profile, published in January of this year in the magazine entitled Public Health, was elaborated starting from interviews with all of the 928 adolescent mothers who had children at the Mário de Moraes Hospital during the study’s two-year period. This number included the 561 mothers who had participated in the research into marijuana and the other mothers who had been excluded from the study because they did not fit into the health profile or because they had consumed other drugs during their pregnancy.

The researchers found a discouraging picture: one in every five adolescents, with an average age of 15 years, was now the mother of a second child, and 90.4% of them were unemployed. More than half of the young women had a low income and up to 7 years of schooling. During pregnancy, 294 said that they had drunk alcohol, 17 marijuana and cocaine and 6 stated that they had used injected drugs. As well as this, 8 out of every 10 adolescents had not wanted to become mothers, and because of their pregnancy 67.3% stopped studying.

To further complicate this picture, during another moment in their lives, a good many of them had already confronted problems of domestic violence, 81 had been attacked with a weapon and 51 young girls had been the victims of sexual violence. Only during the pregnancy period, the police had to be called on 21 occasions to resolve domestic disputes. And, as if the inexperience of the adolescent mother and her lack of maturity were not enough, the team verified that one in three of the youngsters had at least one psychiatric disorder, a very high index that probably represented a further obstacle in the child’s formation and healthy growth. The most frequent diagnosis involved depression, post traumatic stress disorder and anxiety.

In the opinion of Laranjeira, it is highly probable that all of these problems had not developed in an independent manner. “Some studies suggest that the greater the poverty, the lower the educational level and the lower the family support, the greater are the levels of adolescent pregnancy, associated to the consumption of drugs”, he explains. Now the researchers intend to accompany the development of these children both to discover the long term effects of the fetus’ exposure to marihuana and to help and to contribute to their healthy evolution. Nevertheless, up until this moment, what the team has verified was that the effects brought about by the fetus’ exposure to marihuana only add to the other problems found within the environment in which these children are going to grow – some of them are serious, such as exposure to violence – and probably interfere in a significant manner in their future.

The Project
The use of drugs by pregnant adolescents
Thematic Project
Ronaldo Ramos Laranjeira – UNIFESP
R$ 294,854.07 (FAPESP)