Maternal age and blood alcohol concentration in the pregnant Long-Evans rat.

Despite comparable alcohol consumption, not all women who drink excessively give birth to children with fetal alcohol effects or the fetal alcohol syndrome. Various maternal factors may be important in this regard. For example, two recent animal studies found that maternal age was an important risk factor in regard to alcohol's adverse effects on pregnancy. Specifically, alcohol produced greater maternal and fetal toxicity in older and middle-age mothers than in younger cohorts. An age-related difference in maternal blood alcohol concentrations (BACs), despite comparable alcohol administration, may have been the major factor. That is, older mothers may achieve higher BACs or take longer to eliminate alcohol from their blood, resulting in greater maternal and fetal toxicity. The present study was conducted to investigate this possibility. Dams were of three age groups: 2 1/4, 3 3/4 and 5 1/4 months old. Alcohol (3.5 g/kg p.o.) was administered twice daily at a 6-hr interval from gestation days 11 to 19. Blood samples were obtained on gestation day 19 at 1, 2, 4 and 6 hr after each injection. The data showed a progressive increase in peak BACs and a prolonged presence of alcohol with increasing maternal age. It was subsequently hypothesized that age-related differences in percent body water content might account for these effects, and we tested for this possibility. While age-related differences in body water content were found, administering alcohol doses on the basis of body water content did not equate BAC curves across the maternal age groups.(ABSTRACT TRUNCATED AT 250 WORDS)