Effect Of Maternal Alcohol Consumption Research Articles

EFFECT OF PRE- AND POSTNATAL ALCOHOL CONSUMPTION ON GABA LEVELS OF VARIOUS BRAIN REGIONS IN THE RAT OFFSPRING

The effect of maternal alcohol consumption during pregnancy and lactation on gamma-aminobutyric acid (GABA) levels in different rat brain regions of 3-week-old pups was investigated. There was a significant decrease in the thalamus, pons, cerebellum and hippocampus, no change in posterior colliculus, occipital cortex, temporal cortex, hypothalamus, septum or striatum and a significant increase in frontal cortex, olfactory bulbs, anterior colliculus and amygdala. These modifications could be a consequence of alterations in membrane permeability and may be related to the behavioural disorders associated with the fetal-alcohol syndrome.

Pituitary and thyroid hormones in pregnant alcohol-fed rats and their fetuses.

The effect of maternal alcohol consumption on serum and pituitary concentrations of hormones was investigated in pregnant rats and their fetuses. Rats were given 20% ethanol in water prior to pregnancy and 30% ethanol in water throughout gestation, with rat chow ad libitum (alcohol group), or water with an equicaloric diet in which corn starch was substituted for alcohol (pair-fed group), or rat chow and water ad libitum (ad libitum control group). Growth hormone (GH), prolactin (Prl), thyroid-stimulating hormone (TSH), thyroxine (T4), and triiodothyronine (T3) were measured in maternal serum, GH, Prl, and TSH in maternal pituitary, and GH, T4, and T3 in fetal serum. Fetuses of alcohol-fed rats weighed significantly less than fetuses of pair-fed or ad libitum controls. GH, Prl, and TSH were significantly reduced in the maternal serum of alcohol and pair-fed rats compared to ad libitum controls, but T4 and T3 did not differ among the three groups. Pituitary GH was reduced in the alcohol-fed rats, but pituitary Prl and TSH did not differ among the three groups. In the fetuses, neither GH nor T4 differed among the three groups. Fetal T3 was not detectable by this assay. It is suggested that alcohol ingestion affects maternal growth hormone levels, possibly by influencing either the synthesis or the release of the hormone from the pituitary gland. The other hormonal changes may be the result of the reduced food intake, rather than a specific effect of alcohol.

MODERATE ALCOHOL CONSUMPTION DURING PREGNANCY REDUCES BIRTH WEIGHT

The effect of maternal alcohol consumption in the first trimester on birth weight was studied prospectively in 34,660 pregnancies from the Walnut Creek Birth Defects Study (NICHD). Complete medical and demographic information was available in 28,698 live births. Drinking showed a dose-response effect on birth weight; mean birth weight decreased as daily alcohol consumption increased. When adjustment was made for confounding factors (smoking, parity, age, etc.), multiple linear regression revealed an estimated decrease in birth weight of 16 grams for women consuming <1 drink, 86 grams for 1-2 drinks, 169 grams for 3-5 drinks and 127 grams for 6 or more drinks daily compared to non-drinkers (R2=.26, p<.0001). When birth weight below the 10th percentile for gestational age, sex, and race was examined, rates were 6.0%, 6.8%, 11.5%, 16.8%, and 17.7% in non-drinkers, and those drinking <1, 1-2, 3-5, and 6 or more drinks per day, respectively. The trend was significant (p<.0001). This relationship remained significant (p<.005) after multiple logistic regression was used to adjust for confounding factors. Drinkers did not deliver significantly earlier than non-drinkers. Because of the large number of subjects, the study was able to demonstrate a statistically significant effect of alcohol on birth weight independent of other confounding factors. Women should be advised that alcohol is associated with intrauterine growth retardation, but that the effect in light drinkers is clinically small.

Maternal alcohol consumption, birth weight, and minor physical anomalies

The effect of maternal alcohol consumption during pregnancy upon neonatal outcome was examined in 278 mother-infant dyads. Accounts of the mother's drug use as well as information about confounding factors were obtained by personal interviews on two occasions during pregnancy and again after delivery. The infants were examined by a standardized procedure for the presence of minor physical anomalies. Alcohol, in moderate amounts, was found to be unrelated to infant birth weight, birth length, or head circumference. Minor physical anomalies associated with fetal alcohol syndrome were no more common in infants exposed to heavy amounts of alcohol in the first trimester than in nonexposed infants. A weak but significant negative correlation between alcohol consumption and gestational age was not accounted for by covariance with emotional stress, parity, socioeconomic status, mother's age, or use of other drugs.