Psych

The Effects of Prenatal Cocaine-Exposure

On Cognitive Development

There are many factors that are integrated into the successful development of a child from Prenatal growth into toddlerhood. Teratogens (outside factors) have a great impact on the babies' inutero development. Some outside factors like second-hand smoke, smog, or fumes from cleaning chemicals can cause negative effects on the child inside the womb. A few major affects from teratogens could result in low birth weight, head circumference, slow physical growth as well as an effect on mental, behavioral and motor skills (Berk, 2003). The environment around the mother provides many of these outside factors affecting the baby's growth. But the main link to teratogens during the gestation period is most likely the mother. Daniel S. Messinger and the National Institute on Drug Abuse found that 2.8% of pregnant women admitted to using illicit drugs during their pregnancy (1996). Through illicit drug use, tobacco use and alcohol use, the mother disrupts her baby's growth with possibly permanent damage.

One illicit drug that has gone through extensive research is cocaine. Prenatal cocaine exposure has shown to affect the baby physically (defects including eye, bone, genital, urinary tract, kidney, heart deformities, as well as brain hemorrhages) and cognitively (through mental delays, motor, attention, and language problems) (Berk, 2003). Cocaine affects the child subtly but significantly because of what the drug does to the body of both the mother and the growing fetus.

Cocaine is an illegal drug that can be either smoked in a crack form, or inhaled in a powder form. According to Charles F. Levinthal, cocaine is a stimulant that increases the production of dopamine in the brain. Along with the desired feeling resulting from the increasing dopamine levels, there are many other things taking place inside of the body after intake not only for the user, but also for the growing organism inside of the user (2005). While the drug is in affect in the body (for about 20 to 30 minutes), Laura E. Berk's research has found that cocaine constricts the user's blood vessels causing oxygen delivered to the developing organism to fall dramatically for 15 minutes following a high dose (2003). This depravation of oxygen to the developing baby is one of the causes of damage. One of the problems that can result from cocaine use during pregnancy is a condition called abruptio placenta. According to Shad H. Deering of the Department of Obstetrics and Gynecology at Madigan Army Medical Center, the condition of abruptio placentae is defined as the premature separation of the placenta from the uterus. Patients with abruptio placentae typically have uterine bleeding, contractions, and fetal distress (2004). With the fetal distress just mentioned, cognitive growth as well as physical growth could be considerably affected. This condition has the rate of 13-35% of occurrence with cocaine abuse during pregnancy (Deering, 2004). Hypertension (increased blood pressure) and increased levels of catecholamines (neurotransmitters or hormones in the brain) are results of cocaine use and are thought to be responsible for a vasospasm (sudden constriction of a blood vessel) in the uterine blood vessels that causes placental separation (Deering, 2004).

Along with this possible condition resulting from cocaine abuse during pregnancy, one could imagine what other affects cocaine has on the fetus during its critical periods of development. Prenatal cocaine exposure is linked to many risk factors, one of which is impairment in the child's cognitive development. Laura E. Berk states in her section on "Prenatal environmental influences", that from the third week of pregnancy, the critical period for the central nervous system - including the brain- begins (2005). With this in mind, the child's cognitive development could be affected from the very beginning of the central nervous system's development to the actual birth of the child. There have been many studies supporting this fact. One of which is a study from the Case Western Reserve University School of Medicine. Their researchers did a study on whether prenatal cocaine-exposure increases the risk of cognitive impairment. Their study took 415 cocaine-exposed infants and 415 of their mothers or primary caregivers to look at the instance of maternal cocaine use and infant development. Urine samples were taken from the women before and periodically during the experiment and screened for drug use. The women tested and used for this experiment were labeled as "high-risk" if they had received no prenatal care, had a history with human services in any of their past pregnancies, had the appearance of intoxication, or had admitted to the staff of their drug use. Of the 415 women in the study, 197 were tested negative for drug use and 218 were tested positive for drug use before and during pregnancy. The women tested positive for drug use were asked to complete a questionnaire recalling the extent of their cocaine use both in the month before they became pregnant and in each trimester. The cocaine-exposed infants were tested for prenatal drug exposure by having their first bowel movement tested for traces of drug metabolites (Klitsch, 2002).

In order to measure how the infants performed cognitively, the researchers issued tests measured by the Bayley Scales of Infant Development. This scale, according to Mareen M. Black Ph.D. of University of Maryland School of Medicine, may be used to describe the current developmental functioning of infants and/or to assist in diagnosis and treatment for infants with developmental disabilities or delays (1999). The infant-mother dyads were asked to come in at least once during the extent of the study. Through this longitudinal experiment, the researchers concluded that cocaine use prior to the infant's birth would affect their cognitive development. Another branch of research from this study showed that the rate of mental retardation in cocaine-exposed children at age two was 4.89 times higher than an average two-year-old in the general population. Along with mental retardation, the study found the percentage of children with mild delays to be almost twice the amount of children with mild delays from the high-risk noncocaine group (Klitsch, 2002).

Similarly to the above study, the National Household Survey on Drug Abuse conducted a nationally representative sample survey as well as an experiment. The experiment's objective was to find the cognitive, motor, and behavioral outcomes of cocaine-exposed infants through three years of age (Messinger et