Alcohol and the fetus

Disentangling the effects of risk factors and clinical care on subnational variation in early neonatal mortality in the United States

OBJECTIVE

Between 1990 and 2010, the U.S ranking in neonatal mortality slipped from 29(th) to 45(th) among countries globally. Substantial subnational variation in newborn mortality also exists. Our objective is to measure the extent to which trends and subnational variation in early neonatal mortality reflect differences in the prevalence of risk factors (gestational age and birth weight) compared to differences in clinical care.

METHODS

Observational study using linked birth and death data for all births in the United States between 1996 and 2006. We examined health service area (HSA) level variation in the expected early neonatal mortality rate, based on gestational age (GA) and birth-weight (BW), and GA-BW adjusted mortality as a proxy for clinical care. We analyzed the relationship between selected health system indicators and GA-BW-adjusted mortality.

RESULTS

The early neonatal death (ENND) rate declined 12% between 1996 and 2006 (2.39 to 2.10 per 1000 live births). This occurred despite increases in risk factor prevalence. There was significant HSA-level variation in the expected ENND rate (Rate Ratio: 0.73-1.47) and the GA-BW adjusted rate (Rate ratio: 0.63-1.68). Accounting for preterm volume (defined as <34 weeks), the number of neonatologist and NICU beds, 25.2% and 58.7% of the HSA-level variance in outcomes was explained among all births and very low birth weight babies, respectively.

CONCLUSION

Improvements in mortality could be realized through the expansion or reallocation of clinical neonatal resources, particularly in HSAs with a high volume of preterm births; however, prevention of preterm births and low-birth weight babies has a greater potential to improve newborn survival in the United States.

[Fetal alcohol syndrome: nervous system damage and clinical phenotype]

Alcohol is much more slowly eliminated in the fetus than in the mother (< 50%). The ethanol and its derivative the acetaldehyde have a constant dose-effect on the development of the nervous system central. The individual susceptibility to alchol teratogenic effect in utero is responsible of variable clinical phenotype. This teratogenicity is constant during all the development of the central nervous system. The diagnosis of fetal alcohol syndrome (FAS) associates three criteria: delay of pre- and postnatal growth, abnormal development of the central nervous system, craniofacial abnormalities. Cerebral malformations are extremely variable, being to relate to the various stages of development of the nervous system central. Neurochimic abnormalities interest mainly the mono-aminergic system. The backwardness is the best known consequence of SAF (34 to 851%). It is not constant. Facial dysmorphic results of joint abnormalities whose none is pathognomonic but whose grouping is evocative. Psychomotor instability is the most frequent expression on the behavioral phenotype.

Maternal physical activity in pregnancy and infant size for gestational age

PURPOSE

To estimate the effect of several types of maternal physical activity in pregnancy on size for gestational age and length of gestation.

METHODS

Telephone interviews, birth certificates, and medical records provided data on physical activity and other factors for a random sample of 291 Colorado residents. Backward polychotomous logistic regression modeling yielded estimates of the odds ratios for size for gestational age (appropriate versus small or large) and length of gestation (term versus pre-term or post-term) in relation to second and third trimester maternal physical activity.

RESULTS

Performance of any moderate or vigorous physical activity for two hours per week or more in any month was associated with a decreased risk of large infant size for gestational age (LGA; odds ratio = 0.3, 95% confidence interval = 0.2, 0.7), but had no significant effect on risk of small infant size for gestational age (SGA; odds ratio (OR) = 0.8, 95% confidence interval (CI) = 0.3, 2.3). Length of gestation was not affected by prenatal physical activity.

CONCLUSIONS

These results suggest that prenatal physical activity may decrease risk of LGA, as might be expected given its salutary effects on glucose tolerance.

Prenatal alcohol exposure and development at preschool age: main results of a French study

Very high levels of alcohol consumption during pregnancy are harmful for the central nervous system of the child and affect morphogenesis and growth. The aim of this study was to investigate the effects of moderate prenatal alcohol exposure on development at preschool age in a longitudinal study. Pregnant women were interviewed on their alcohol consumption during pregnancy at their first visit to the maternity hospital of Roubaix, France. The development of their 160 children was assessed at the age of 4 1/2. Multiple regression analyses indicated that consumption of 1.5 oz of absolute alcohol (approximately 3 drinks) or more during pregnancy was significantly related to a decrease of 7 points on the general cognitive index of the McCarthy scales, after controlling for confounders. This level of consumption was also related to a higher score on minor neurological anomalies, a lower height of the child, and a higher score on facial features. This level of 1.5 oz of absolute alcohol/day should not be interpreted as a biological threshold, because the study does not allow conclusions to be drawn regarding the effects of lower levels of alcohol consumption. Alcohol consumption during pregnancy can affect the development of the child, at levels well below those associated with fetal alcohol syndrome.

Prenatal ethanol exposure alters the expression of intestinal hydrolase mRNAs in newborn rats

To gain insight into the postnatal growth delay induced by ethanol in utero, we characterized functional impairments of the small intestine of neonatal rats prenatally exposed to ethanol using a well-described model of gestational alcoholism (25% ethanol w/v in the drinking water). Expression of the intestinal enzymes-lactase-phlorizin hydrolase (LPH) and intestinal alkaline phosphatase (IAP)-that are critical for enteral nutrition of neonates was studied. Characteristic patterns of LPH and IAP expression along the proximal-distal (horizontal) and crypt-villus (vertical) axes of the small intestine, as well as the intracellular localization of LPH and IAP mRNAs and immunoreactive proteins within absorptive enterocytes, were not altered by prenatal exposure to ethanol. However, a 10- to 15-fold increase in the number of LPH and IAP mRNA molecules per absorptive enterocyte was found throughout the intestine of ethanol-exposed neonates, compared with controls, whereas lactase and alkaline phosphatase activities per enterocyte remained unchanged. These findings suggest that ethanol in utero alters the mRNA abundance of epithelial enzymes in newborn rat small intestine. Changes in mRNA abundance could be an important aspect of enterocyte adaptation to high ethanol concentrations in gastrointestinal amniotic fluid of ethanol-exposed fetuses.

Stress, social support and pregnancy outcome: a reassessment based on recent research

We present an assessment of studies published in the last decade that consider the relationship of stress and social support to preterm delivery or fetal growth retardation. Included in the review are all reports on the direct effects of stressors or psychological distress; the indirect effects of stressors or distress through health behaviours such as smoking; and the direct and buffering effects of social support. Although an important stimulus for recent stress research has been the attempt to explain racial and social class differences in birth outcome, the recent data show that stressful life events during pregnancy, though more common in disadvantaged groups, do not increase the risk of preterm birth. In contrast, intimate social support from a partner or family member appears to improve fetal growth, even for women with little life stress. Questions unanswered by the research to date are whether elevated levels of depressive symptoms affect pregnancy outcome, either directly or by encouraging negative health behaviours, and whether chronic (vs. acute) stressors are harmful. Additional research is also needed to determine whether psychosocial factors interact with specific clinical conditions to promote adverse pregnancy outcomes. Focusing on intimate support and how it benefits pregnancy outcome could lead to the design of more effective interventions.

Moderate prenatal alcohol exposure and psychomotor development at preschool age

OBJECTIVES

This study investigated the effect of moderate prenatal alcohol exposure on psychomotor development of preschool-age children in a longitudinal study.

METHODS

Pregnant women were interviewed about their alcohol consumption at their first visit to the maternity hospital in Roubaix, France. Alcohol consumption before pregnancy and during the first trimester was assessed with a structured questionnaire. The psychomotor development of 155 children of these women was assessed with the McCarthy scales of children's abilities when the children were about 4 1/2 years old.

RESULTS

Consumption of 1.5 oz of absolute alcohol (approximately three drinks) or more per day during pregnancy was significantly related to a decrease of 7 points in the mean score on the general cognitive index of the McCarthy scales, after gender, birth order, maternal education, score for family stimulation, family status, maternal employment, child's age at examination, and examiner were controlled for.

CONCLUSIONS

This study showed that moderate to heavy alcohol consumption during pregnancy, at levels well below those associated with fetal alcohol syndrome, has effects on children's psychomotor development.

Recall bias in a case-control study of low birth weight

The role of report/recall bias in case-control studies of low birth weight (LBW) was investigated in women who gave birth at a tertiary hospital. Prenatal exposure information reported at the postpartum interview was compared with that documented during pregnancy in obstetric records. 169 cases of LBW and 198 controls were selected. The two sets of information on case mothers and control mothers were compared, using the medical record as a reference. Kappa values were estimated. No trend was observed to increase/decrease the sensitivity and specificity of recall. Agreement on alcohol use was very low (kappa = 0.11 for case mothers and 0.03 for control mothers): on obstetrical records, only 12 mothers of cases reported habitual alcohol intake at the first prenatal care visit, whereas in the interview 69 said yes to the same question; in control mothers, the figures were 4 and 89 respectively. Odds ratios (ORs) of exposure estimated from the two sets of data did not differ importantly in 8 variables. Interview data yielded ORs for hypertension (8.39 versus 4.63), anemia (0.44 versus 0.99) that were farther from the null, and ORs in the opposite direction for alcohol (0.83 versus 1.61) and any drug (0.64 versus 1.42). In conclusion, given that OR figures are similar for most variables and no trend is observed in sensitivity/specificity, mothers of normal births can be an adequate reference group, using personal interviews to obtain information on lifestyle, and medical records for conditions.

Moderate alcohol consumption in pregnancy and subsequent left-handedness

Alcohol in high doses is neurotoxic to the developing brain but it is not yet settled whether small doses give rise to more subtle effects. The aim of the study was to establish whether a moderate intake of alcohol in pregnancy would increase the frequency of left-handedness in the offspring. Such an association could indicate a possible subtle prenatal neurotoxic effect. This was a follow-up study of a group of pregnant women who took part in a community trial in 1984 to 1987. Data on alcohol consumption were reported by consecutively sampled pregnant women in the 36th week of gestation. Hand preference for their offspring was reported by the mothers in a self-administered questionnaire when their children were 5 to 9 years old. Ninety-one percent participated in the follow-up study. The study showed that 9.1% of the children were left-handed, with a higher prevalence among boys (11.8%). Results showed a slightly higher frequency of being left-handed among children exposed to alcohol in fetal life, but the findings were not statistically significant at a 0.05 level.

Attitudes and behavior of pregnant women and health professionals towards alcohol and tobacco consumption

The objective of this study was to identify those factors that influence pregnant women's behavior towards alcohol consumption, so that they could be taken into account when developing alcohol prevention programs in prenatal care. Tobacco use was also studied to identify similarities and differences in attitudes and behavior. A sample of 176 women was interviewed using a structured questionnaire in the prenatal clinics or post-partum wards. Most women were aware that alcohol and tobacco could be harmful to their babies; however heavy drinkers recognized the influence of alcohol in pregnancy less often than the others. Sixty percent of the women, even among the light drinkers, thought that two drinks per day was a reasonable level of consumption during pregnancy. When asked who could be helpful in decreasing their alcohol consumption, most women mentioned their husband, and the doctor or midwife. This is in contrast to our finding that less than 20% of heavy drinkers were advised to reduce alcohol consumption, as compared to 70% of heavy smokers. The results point to the potential for more active interventions on alcohol reduction by health personnel during prenatal care.