Gestational weight gain, prepregnancy body mass index and offspring attention-deficit hyperactivity disorder symptoms and behaviour at age 10.

OBJECTIVE: To assess offspring attention-deficit hyperactivity disorder (ADHD) symptoms and emotional/behavioural impairments at age 10 years in relation to maternal gestational weight gain (GWG) and prepregnancy body mass index (BMI). DESIGN AND SETTING: Longitudinal birth cohort from Magee-Womens Hospital, Pittsburgh, Pennsylvania (enrolled 1983-86). POPULATION: Mother-infant dyads (n = 511) were followed through pregnancy to 10 years. METHODS: Self-reported total GWG was converted to gestational-age-standardised z-scores. Multivariable linear and negative binomial regressions were used to estimate effects of GWG and BMI on outcomes. MAIN OUTCOME MEASURES: Child ADHD symptoms were assessed with the Conners' Continuous Performance Test. Child behaviour was assessed by parent and teacher ratings on the Child Behaviour Checklist (CBCL) and Teacher Report Form, respectively. RESULTS: The mean (SD) total GWG (kg) was 14.5 (5.9), and 10% of women had a pregravid BMI ≥30 kg/m2 . Prepregnancy obesity (BMI of 30 kg/m2 ) was associated with increased offspring problem behaviours including internalising behaviours (adjusted ß 3.3 points, 95% CI 1.7-4.9), externalising behaviours (adjusted ß 2.9 points, 95% CI 1.4-4.6), and attention problems (adjusted ß 2.3 points, 95% CI 1.1-3.4) on the CBCL, compared with normal weight mothers (BMI of 22 kg/m2 ). There were nonsignificant trends towards increased offspring impulsivity with low GWG among lean mothers (adjusted incidence rate ratio 1.2, 95% CI 0.9-1.5) and high GWG among overweight mothers (adjusted incidence rate ratio 1.7, 95% CI 0.9-2.8), but additional outcomes did not differ by GWG z-score. Results were not meaningfully different after excluding high-substance users. CONCLUSIONS: In a low-income and high-risk sample, we observed a small increase in child behaviour problems among children of obese mothers, which could have an impact on child behaviour in the population. TWEETABLE ABSTRACT: Maternal obesity is associated with a small increase in child behaviour problems.

Genome-wide copy-number variation study of psychosis in Alzheimer's disease.

About 40-60% of patients with late-onset Alzheimer's disease (AD) develop psychosis, which represents a distinct phenotype of more severe cognitive and functional deficits. The estimated heritability of AD+P is ~61%, which makes it a good target for genetic mapping. We performed a genome-wide copy-number variation (CNV) study on 496 AD cases with psychosis (AD+P), 639 AD subjects with intermediate psychosis (AD intermediate P) and 156 AD subjects without psychosis (AD-P) who were recruited at the University of Pittsburgh Alzheimer's Disease Research Center using over 1 million single-nucleotide polymorphisms (SNPs) and CNV markers. CNV load analysis found no significant difference in total and average CNV length and CNV number in the AD+P or AD intermediate P groups compared with the AD-P group. Our analysis revealed a marginally significant lower number of duplication events in AD+P cases compared with AD-P controls (P=0.059) using multivariable regression model. The most interesting finding was the presence of a genome-wide significant duplication in the APC2 gene on chromosome 19, which was protective against developing AD+P (odds ratio=0.42; P=7.2E-10). We also observed suggestive associations of duplications with AD+P in the SET (P=1.95E-06), JAG2 (P=5.01E-07) and ZFPM1 (P=2.13E-07) genes and marginal association of a deletion in CNTLN (P=8.87E-04). We have identified potential novel loci for psychosis in Alzheimer's disease that warrant follow-up in large-scale independent studies.

Prenatal marijuana exposure, age of marijuana initiation, and the development of psychotic symptoms in young adults.

BACKGROUND: Studies have demonstrated that an early age of onset of marijuana use (EAOM) is associated with a higher risk of developing psychotic symptoms (PS) compared to initiating marijuana use at a later age or not at all. Research has also found that prenatal marijuana exposure (PME) predicts EAOM. This report evaluates the relationships among PME, EAOM, and PS. METHOD: Subjects were initially interviewed in their fourth prenatal month. Women and offspring who completed the birth assessment (n = 763) were selected for follow-up. Women and their offspring were followed until the offspring were 22 years of age: 596 offspring were evaluated. At age 22, PS were assessed in the offspring with the Diagnostic Interview Schedule using DSM-IV criteria. Analyses controlled for significant covariates including other prenatal substance exposures, race, gender, and offspring substance use at 22 years. RESULTS: PME and EAOM significantly predicted increased rates of PS at 22 years controlling for other significant covariates. The direct effect of PME on PS was marginally significant (p = 0.06) when EAOM was entered into the model and other covariates were fixed. In the mediation analysis, EAOM did not significantly mediate the association between PME and PS, controlling for significant covariates, nor was the indirect pathway significant when structural equation modeling was used. The total effect of the direct and indirect pathways was significant. CONCLUSIONS: In addition to EAOM, PME may also play a role in the association between marijuana use and the development of PS. This could highlight a new area for prevention.

Prenatal alcohol exposure predicts continued deficits in offspring size at 14 years of age.

BACKGROUND: Growth deficits are among the cardinal features for the diagnosis of fetal alcohol syndrome. Growth deficits have also been noted among those who were exposed to alcohol prenatally but who do not have fetal alcohol syndrome. Few studies have observed subjects past early and middle childhood, however, to evaluate the longer-term effects of prenatal alcohol exposure on growth in adolescence. This is a report of the effects of alcohol exposure during gestation on the size of the offspring at 14 years of age. METHODS: Women were recruited in their fourth prenatal month. These women were interviewed in the fourth and seventh months of pregnancy and at delivery. The women and their children were seen when the offspring were 14 years of age. RESULTS: Growth deficits associated with prenatal alcohol exposure were identified among the offspring at 14 years of age. Weight, height, head circumference, and skinfold thickness continued to be significantly affected by prenatal alcohol exposure after controlling for other significant predictors of size. These effects exhibited a dose-response pattern, and significant effects were found at levels below one drink per day. For example, first trimester alcohol exposure predicted weights of 152 lbs for the offspring of abstainers, 149 lbs for the offspring of light drinkers (>0 and <0.2 drinks per day), 143 lbs for the offspring of moderate drinkers (>0.2 and <0.89 drinks per day), and 136 lbs for the offspring of heavy drinkers (>0.89 drinks per day). CONCLUSIONS: Prenatal alcohol exposure continues to affect size at age 14 years in this cohort of children followed since their fourth month of gestation.

Suitability of the Cordis Stabilizer marker guide wire for quantitative coronary angiography calibration: an in vitro and in vivo study.

Catheters usually are used for calibration purposes in quantitative coronary angiography (QCA). The systematic and random errors in these calibration factors (CFs) are dependent on the size and quality of the catheters and limited by out-of-plane magnification (OPM). Theoretically, a guide wire with evenly spaced marker bands would solve many of these potential problems. For this reason, we tested the Cordis Stabilizer marker wire, featuring 10 radiopaque platinum marker bands 15 mm apart, in in vitro and in vivo studies. To assess the effect of foreshortening, wires were positioned in a tube phantom; a centimeter grid was used as the gold standard. Radiographic images were acquired at 5-inch and 7-inch image-intensifier sizes, 512(2) and 1,024(2) matrix sizes and angulations from 0 degrees to 70 degrees in steps of 10 degrees. It was concluded that the relative errors in CFs are less than 7% if the foreshortening angles remain less than 20 degrees. In DICOM images of 15 patients, 65 measurements were taken after calibration on an 8F catheter and on a guide wire positioned in the coronary lesion. In all but two cases, the wire CFs were larger than the catheter CFs (relative difference, 24.7 +/- 19.6%). The measurements were divided into four groups: (I) no apparent OPM or foreshortening (n = 7), (II) only OPM (n = 4), (III) only foreshortening (n = 10), and (IV) the combination of both (n = 44). In group I (no OPM or foreshortening) the QCA results were similar using the guide wire or catheter as the calibration device (relative CF difference, 2.9% only). In group III the diameters were overestimated using the guide wire (obstruction diameter difference, 0.22 +/- 0.11 mm; reference diameter difference, 0.35 +/- 0.06 mm). For only OPM (group II) and the combination of OPM and foreshortening (group IV), the lesion length was underestimated on average by 2.4 mm using the catheter instead of the guide wire. In conclusion, if accurate assessment of the lesion length is important, the marker wire should be used for calibration purposes. For vessel diameter measurements, the conventional catheter calibration approach is the method of choice.

Effects of prenatal tobacco exposure on preschoolers' behavior.

This is a longitudinal study of the relationship between prenatal tobacco exposure and the development of behavior problems in 672 children at the age of 3 years. Women from a prenatal clinic were interviewed about substance use at the end of each trimester of their pregnancy and at 3 years postpartum. Children were assessed at the age of 3 years with maternal ratings of behavior problems, activity, and attention. The prevalence of tobacco use was high in this cohort; 54.3% and 52.3% of the women smoked tobacco in the first and third trimesters of pregnancy, respectively. At 3 years postpartum, 61.6% of the women were smokers. There were significant effects of prenatal tobacco exposure on the children's behavior at age 3 years. Increases in scores on the Oppositional Behavior, Immaturity, Emotional Instability, Physical Aggression, and Activity scales and in the total score on the Toddler Behavior Checklist (TBC) were significantly associated with prenatal tobacco exposure. Smoking one pack of tobacco cigarettes per day during the third trimester of pregnancy was associated with an increase of 6 points in the total problem behavior score. Among the subscales of the TBC, tobacco exposure had the largest effect on oppositional behavior. Impulsivity and peer problems were associated with both prenatal and current tobacco exposure. Only current tobacco exposure predicted attention problems. Prenatal tobacco exposure had a significant negative effect on the development of behavior problems among preschoolers.

Effects of prenatal marijuana exposure on child behavior problems at age 10.

This is a prospective study of the effects of prenatal marijuana exposure on child behavior problems at age 10. The sample consisted of low-income women attending a prenatal clinic. Half of the women were African-American and half were Caucasian. The majority of the women decreased their use of marijuana during pregnancy. The assessments of child behavior problems included the Child Behavior Checklist (CBCL), Teacher's Report Form (TRF), and the Swanson, Noland, and Pelham (SNAP) checklist. Multiple and logistic regressions were employed to analyze the relations between marijuana use and behavior problems of the children, while controlling for the effects of other extraneous variables. Prenatal marijuana use was significantly related to increased hyperactivity, impulsivity, and inattention symptoms as measured by the SNAP, increased delinquency as measured by the CBCL, and increased delinquency and externalizing problems as measured by the TRF. The pathway between prenatal marijuana exposure and delinquency was mediated by the effects of marijuana exposure on inattention symptoms. These findings indicate that prenatal marijuana exposure has an effect on child behavior problems at age 10.

Effects of prenatal cocaine/crack and other drug exposure on electroencephalographic sleep studies at birth and one year.

OBJECTIVE: Little is known about the neurophysiologic effects of prenatal cocaine/crack use. The aim of this study, designed to overcome methodologic limitations of previous research, was to investigate the effects of prenatal cocaine use on electroencephalographic (EEG) sleep patterns, a marker of central nervous system development. METHODS: In a longitudinal study of prenatal cocaine/crack exposure, women were interviewed at the end of each trimester about cocaine, crack, alcohol, tobacco, marijuana, and other drug use. Two-hour paper- and computer-generated EEG sleep recordings were obtained on a sample of the full-term infants on the second day of life and at 1 year postpartum. Eligible newborns were full-term, had received no general anesthesia, and had a 5-minute Apgar score >5. All infants whose mothers used one or more lines of cocaine during their first trimester or any crack (n = 37) were selected. A comparison group was chosen randomly from the group of women who did not use cocaine or crack during their pregnancy (n = 34). RESULTS: Women who used cocaine/crack during the first trimester were older, less educated, less likely to be working, and used more tobacco, alcohol, marijuana, and other illicit drugs than women who did not use cocaine/crack during the first trimester. There were no differences in infant birth weight, length, head circumference, or gestational age between the two exposure groups. After controlling for the significant covariates, prenatal cocaine exposure was associated with less well developed spectral correlations between homologous brain regions at birth, and with lower spectral EEG power values at 1 year of age. Prenatal alcohol, marijuana, and tobacco use were found to affect state regulation and cortical activities. CONCLUSIONS: These results indicate that the neurotoxic effects of prenatal cocaine/crack use can be detected with quantitative EEG measures.

Economic evaluation of enoxaparin as postdischarge prophylaxis for deep vein thrombosis (DVT) in elective hip surgery.

OBJECTIVES: Clinical trials indicate enoxaparin thromboprophylaxis (Clexane) can be effective and safe when used in an outpatient setting and that extending the length of thromboprophylaxis with enoxaparin to the postdischarge period may be more effective than inpatient thromboprophylaxis alone. This may increase the cost of thromboprophylaxis. The objective of the study was to estimate the expected cost-effectiveness of using enoxaparin for hospital admission only vs. enoxaparin for hospital admission and for 21 days postdischarge. METHODS: Decision analysis was used to combine probability, resource use and unit cost data, using the framework of cost-effectiveness analysis. The model used a societal perspective to estimate the expected costs of treatment and outcomes to patients undergoing orthopedic surgery for elective hip replacement. Incremental cost-effectiveness ratios were calculated to provide estimates of the cost per life gained, cost per year life year gained and cost per quality-adjusted life year gained with extended use of enoxaparin thromboprophylaxis. RESULTS: There was an expected cost per quality-adjusted life year gained of pounds 5732 associated with extended enoxaparin thromboprophylaxis. The results were sensitive to the percentage of patients who could administer enoxaparin injections at home, the rate of DVT associated with standard enoxaparin thromboprophylaxis and the rate of PE associated with standard and extended enoxaparin thromboprophylaxis. CONCLUSIONS: The analyses indicated that in most cases extended enoxaparin thromboprophylaxis resulted in increased costs for health care services. In all cases, extended thromboprophylaxis with enoxaparin was associated with improved survival and life-years gained.

Growth of infants prenatally exposed to cocaine/crack: comparison of a prenatal care and a no prenatal care sample.

OBJECTIVE: It has not been possible to draw firm conclusions about the effects of prenatal cocaine exposure because of methodologic problems involved in the conduct of this research. This study, designed to overcome some of these methodologic problems, is a prospective, longitudinal investigation of the effects of prenatal cocaine/crack exposure on neonatal growth in two samples, one with and one without prenatal care (PC). METHODS: Women in the PC sample (n = 295) were interviewed at the end of each trimester about their use of cocaine, crack, alcohol, tobacco, marijuana, and other drugs. Women in the no prenatal care (NPC) sample (n = 98) were interviewed at delivery about their drug use during each trimester of pregnancy. In both samples, information was also obtained about sociodemographic, lifestyle, psychologic, and social support characteristics. Both samples consisted of women who were predominantly low income, single, and high school educated. Of the women, 48% in the PC sample were black; 81% in the NPC sample were black. Infants were examined during the postpartum hospital stay by project nurses who were blind to maternal substance use status. RESULTS: Women in both samples who used cocaine/crack during pregnancy were older, had lower family incomes, and used more alcohol than did women who did not use cocaine/crack during pregnancy. In addition, women in the NPC sample were more likely to be black, less educated, gained less weight during pregnancy, and used more alcohol than did women in the PC sample, regardless of cocaine use. In both samples, cocaine/crack use during early pregnancy predicted reduced gestational age, birth weight, length, and head circumference, after controlling for the significant covariates of cocaine use. In a comparison of the samples, the offspring of the NPC/cocaine group were significantly smaller than were the offspring of the PC/no cocaine group, whereas the offspring of the PC/cocaine and NPC/cocaine groups did not differ. CONCLUSIONS: These results indicate that exposure to cocaine/crack during early pregnancy decreases the intrauterine growth of exposed offspring in women with and without PC. Each of the growth parameters was affected indicating symmetric growth retardation. The adequacy of PC was not a significant factor in determining the difference between cocaine-exposed and nonexposed infants. These samples are being followed throughout childhood to determine whether there are long-term effects of prenatal cocaine/crack exposure on growth.

Prenatal alcohol use and offspring size at 10 years of age.

The Maternal Health Practices and Child Development Project is a longitudinal study of the effects of prenatal exposure to alcohol and other substances. Women were selected from a prenatal clinic and interviewed at the 4th and 7th months of pregnancy. Their offspring were examined at delivery, at 8 and 18 months, and at 3, 6, and 10 years. This report examined 610 offspring, at age 10, who were exposed prenatally to alcohol. Most alcohol use in this low-income cohort was light to moderate, although the entire spectrum of alcohol use is represented. The weight, length, head circumference, and skinfold thickness of the offspring were measured. At each assessment phase, we found a significant association between size and prenatal exposure to alcohol. At age 10, the children who were prenatally exposed to alcohol continued to be significantly smaller in weight, height, head circumference, and skinfold thickness. These results indicate that prenatal alcohol exposure has a long-term impact on offspring growth.

Prenatal substance exposure: effects on attention and impulsivity of 6-year-olds.

Attention and impulsivity of prenatally substance-exposed 6 year olds were assessed as part of a longitudinal study. Most of the women were light to moderate users of alcohol and marijuana who decreased their use after the first trimester of pregnancy. Tobacco was used by a majority of women and did not change during pregnancy. The women, recruited from a prenatal clinic, were of lower socio-economic status, and over half were African American. Attention and impulsivity were assessed using a Continuous Performance Task. Second and third trimester tobacco exposure and first trimester cocaine use predicted increased omission errors. Second trimester marijuana use predicted more commission errors and fewer omission errors. There were no significant effects of prenatal alcohol exposure. Lower Stanford-Binet Intelligence Scale composite scores, male gender, and an adult male in the household also predicted more errors of commission. Lower SBIS composite scores, younger child age, maternal work/ school status, and higher maternal hostility scores predicted more omission errors. These findings indicate that prenatal substance use has an effect on attentional processes.

Prenatal cocaine exposure. A longitudinal study of development.

The current study examines the effect of prenatal cocaine use on physical, cognitive, and behavioral development at birth, 1, 3, and 7 years, controlling for other factors that affect child development. Women who used cocaine during pregnancy were more likely to be single and to use alcohol, marijuana, and tobacco than were women who did not use cocaine. Prenatal cocaine use was associated with reduced gestational age, but not with birth weight, length, or head circumference. Neonatal neurobehavioral assessments were affected by prenatal cocaine exposure. Growth at 1 year was not affected by prenatal cocaine use. At 3 years, prenatal cocaine use was a significant predictor of head circumference and of the composite score on the Stanford-Binet Intelligence Scale (4th edition). Prenatal cocaine use was also associated with temperamental differences at 1 and 3 years and with behavior problems at 3 years. These findings represent a pattern of central nervous system effects, related to prenatal cocaine exposure, which is predicted by the teratologic model.

Effects of prenatal substance exposure: altered maturation of visual evoked potentials.

We investigated the effects of prenatal substance use on visual evoked potentials (VEPs). Seventy-four children were tested at birth and 1 month of age with binocular flash VEPs and at 4, 8, and 18 months of age with binocular pattern VEPs. Regressions were run by trimester to assess the independent effects of substance exposure. Variables included in the regression model were alcohol, marijuana, tobacco, other drug use for each trimester, maternal age, education, income, race, marital status, infant sex, birthweight, and Dubowitz score. Changes in specific components of the binocular VEP were both substance- and trimester-specific. First trimester alcohol use was associated with prolonged P1 wave latencies at 1 month of age. Prolonged P1 wave latencies at birth and 18 months were associated with tobacco use during each of the three trimesters, at 1 and 18 months with third trimester marijuana use, and at 1 and 18 months with first trimester other illicit drug use. Although these women were moderate substance users during pregnancy, their offspring exhibited maturational changes in components of the VEP in the absence of neonatal behavioral disturbances.

Prenatal cocaine exposure: effects on the development of school-age children.

The offspring of 28 women who reported light to moderate cocaine use during pregnancy were compared with those of 523 women who reported no cocaine use during pregnancy and none for the year prior to pregnancy. Subjects were participants in two prospective, longitudinal studies of prenatal substance use. Women were interviewed during their fourth and seventh months of pregnancy, at delivery, and at 8, 18, 36, and 72 months postpartum regarding cocaine, alcohol, marijuana, tobacco, and other drug use. At 6 years, children underwent physical examination, and their cognitive development, academic achievement, and behavior were assessed. The women in the cocaine group were more likely to be Caucasian and to use more alcohol, marijuana, tobacco, and other illicit drugs than those in the comparison group. When demographic and substance use differences between the groups were controlled, there were no significant effects of prenatal cocaine exposure on the growth, intellectual ability, academic achievement, or teacher-rated classroom behavior of the 6-year-old offspring. Children prenatally exposed to cocaine did show deficits in their ability to sustain attention on a computerized vigilance task.

The effects of prenatal cocaine use on neonatal neurobehavioral status.

The effect of prenatal cocaine use on neonatal behavior was examined, using the Brazelton Neonatal Behavioral Assessment Scale (BNBAS), in a prospective study of women attending a prenatal clinic. Women were interviewed at the end of each trimester. Term infants were assessed with the BNBAS at day 2 (N = 165) (mean = 35.6 h) and at day 3 (N = 108) (mean = 60.1 h). Women averaged 25 years of age with 12 years of education; 48% were African-American and 20% were married. Women who used cocaine were more likely to use tobacco, alcohol, and marijuana. Regression analyses, with the Lester et al. (22) clusters as outcomes, were used to control for covariates of cocaine use such as other substance use and sociodemographic characteristics. On day 2, first, second, and third trimester cocaine/crack use were significantly related to poorer autonomic stability, second and third trimester use were related to poorer motor maturity and tone, and first and second trimester use were associated with an increased number of abnormal reflexes. These relationships were not present on day 3. These results may be transient expressions of the effect of prenatal cocaine exposure on central nervous system maturation.

Prenatal alcohol exposure and academic achievement at age six: a nonlinear fit.

This is a report on the effects of prenatal alcohol exposure on the academic achievement of children at 6 years of age. In this longitudinal study, women were interviewed at the end of each trimester of pregnancy, at delivery, and at 8, 18, 36, and 72 months postpartum. The women were of lower socioeconomic status, high school-educated, and moderate users of alcohol. The offspring received age-appropriate physical and developmental assessments at each follow-up. Linear regression and nonlinear curve fitting were used to investigate the nature and shape of the relationship between prenatal alcohol exposure and achievement. In addition, the role of child IQ in this relationship was explored. Alcohol exposure during the second trimester predicted deficits in each of the three subtests of the Wide Range Achievement Test-Revised (WRAT-R): reading, spelling, and arithmetic. The relationship was partially reduced by the addition of IQ to the model, but prenatal alcohol exposure still predicted significant deficits in achievement, even after controlling for IQ. Tests for the shape of the relationship demonstrated that the effect of prenatal exposure on the arithmetic subtest of the WRAT-R was a linear or dose-response relationship. By contrast, the relationships between prenatal alcohol exposure and performance on the spelling and reading subtests of the WRAT-R were better modeled as threshold effects. The thresholds for both were approximately 1 drink/day in the second trimester.

Prenatal exposure to alcohol and marijuana: effects on motor development of preschool children.

Gross motor development of preschool children prenatally exposed to alcohol and marijuana was assessed as part of a longitudinal study. Most mothers in the study were light to moderate users and discontinued or decreased use of alcohol and marijuana after the first trimester of pregnancy. The women were of lower socioeconomic status, half of the sample was African-American, and most were single. Gross motor development was evaluated with balance and ball-handling items at 3 years. Balance items included walking on a line, walking on a balance beam, standing on one foot, standing on tiptoes, and stair climbing and descent. Ball-handling items included catching, throwing, and kicking a ball. Refusal to perform items was also recorded. Prenatal alcohol and marijuana exposure did not negatively affect gross motor development. The composite score on the Stanford-Binet Intelligence Scale, age at assessment, gender, and examiner were significant predictors of gross motor performance and of refusal to participate in the balance items. The ponderal index, number of siblings, current income, examiner, current maternal use of tranquilizers, and first trimester exposure to amphetamines were also significant predictors of balance skills. Gender and number of hospitalizations predicted refusal to participate in balance items, whereas hearing and vision problems predicted refusal on ball-handling items. The components of timing, speed, and fine motor control have not been addressed in this study, and therefore it is premature to conclude that there is no impact of prenatal substance use on motor development.

Cost effectiveness of antenatal screening for cystic fibrosis.

OBJECTIVE: To estimate the cost effectiveness of different antenatal screening programmes for cystic fibrosis. SETTING: Antenatal clinics and general practices in the United Kingdom. DESIGN: Four components of the screening process were identified: information giving, DNA testing, genetic counselling, and prenatal diagnosis. The component costs were derived from the literature and from a pilot screening study in Yorkshire. The cost of a given screening programme was then obtained by summing the components according to the specific screening strategy adopted (sequential and couple), the proportion of carriers detected by the DNA test, and the uptake of screening. Baseline assumptions were made about the proportion with missing information on carrier status from previous pregnancies (20%), the proportion changing partners between pregnancies (20%), and the uptake of prenatal diagnosis (100%). Sensitivity analysis was performed by varying these assumptions. MAIN OUTCOME MEASURE: Cost per affected pregnancy detected. RESULTS: Under the baseline assumptions sequential screening costs between pounds 40,000 and pounds 90,000 per affected pregnancy detected, depending on the carrier detection rate and uptake. Couple screening was more expensive, ranging from pounds 46,000 to pounds 104,000. From the sensitivity analysis a 10% change in the assumed proportion with missing information from a previous pregnancy alters the cost by pounds 4000; a 10% change in the proportion with new partners has a similar effect but only for couple screening; and cost will change directly in proportion to the uptake of prenatal diagnosis. CONCLUSIONS: While economic analysis cannot determine screening policy, the paper provides the NHS with the information on cost effectiveness needed to inform decisions on the introduction of a screening service for cystic fibrosis.

Prenatal alcohol, marijuana, and tobacco use: infant mental and motor development.

These data are from a longitudinal study of prenatal alcohol and marijuana use in a low income sample. Half of the women were black and half were white. Women who used alcohol and/or marijuana during their pregnancies were light to moderate users; most decreased or discontinued their use after the first trimester. At the first follow-up phase, which occurred at a median age of 9 months, the children were functioning above average on the Bayley Scales of Infant Development (BSID). Prenatal alcohol and tobacco use did not predict BSID mental or motor scores at this phase. Third trimester marijuana use was associated with decreased BSID mental scores. Age at assessment was the most important predictor at this phase. The second follow-up occurred at a median age of 19 months when the group means for the BSID were lower. Prenatal alcohol and marijuana use did not predict outcome at this phase. Prenatal and current cigarette use were associated with decreased BSID mental scores. Demographic and environmental variables were important predictors at this phase.