Amniocentesis in the second trimester and congenital talipes equinovarus in the offspring: a population-based record linkage study in Scotland.

BACKGROUND: To investigate whether amniocentesis in the second trimester is associated with congenital talipes equinovarus (CTEV) in the offspring. METHODS: Case-control study nested within a population-based cohort, developed through linkage of the Scottish Congenital Anomalies Linked Database with records of amniocentesis from cytogenetics laboratories, including 564,299 singleton births 1992-2001. Odds ratios and 95% confidence intervals for CTEV in the offspring (isolated, non-isolated, total) were calculated using logistic regression, adjusting for maternal age, year of birth and health board of birth. RESULTS: There was a modest positive association between total CTEV and amniocentesis at any time (OR = 1.27, 95% CI 0.99-1.65) and at >or= 15 weeks (OR = 1.25, 95%CI 0.95-1.64). The association was strongest for non-isolated CTEV (amniocentesis any time: OR = 1.68, 95%CI 1.08-2.61; amniocentesis >or= 15 weeks: OR = 1.81, 95%CI 1.16-2.83). Amniocentesis at >or= 20 weeks was associated with increased risk of total (OR = 5.87, 95% CI 3.38-10.21), non-isolated (OR = 13.17, 95% CI 6.49-26.74) and isolated CTEV (OR = 3.10, 95% CI 1.28-7.49). There were no associations in mothers aged >or= 35 years. CONCLUSIONS: The modest association observed is most likely accounted for by amniocenteses conducted because of an earlier abnormal prenatal test. Thus, second trimester amniocentesis is unlikely to contribute to the development of CTEV in the offspring.

Pedigree analysis and epidemiological features of idiopathic congenital talipes equinovarus in the United Kingdom: a case-control study.

BACKGROUND: Congenital talipes equinovarus (CTEV) is a common developmental disorder of the foot, affecting between 1 and 4.5 per 1000 live births. The aetiology is not well elucidated. While both genetic and environmental factors are implicated, no specific genes have been identified and little is known about environmental risk factors. METHODS: We conducted a case-control study of idiopathic congenital talipes equinovarus (ICTEV) in the United Kingdom. 194 cases and 60 controls were recruited. Pedigrees were obtained for 167 cases. RESULTS: The rank of the index pregnancy, maternal education and caesarean delivery were significantly associated with ICTEV risk in a multivariate model. There were suggestions that maternal use of folic acid supplements in the three months before the pregnancy decreased ICTEV risk, and that parental smoking during the pregnancy increased risk, although the associations were not statistically significant. One quarter of pedigrees showed a family history of CTEV, and autosomal dominant inheritance was suggested in some of these. CONCLUSION: Uterine restriction did not appear to have a strong influence on ICTEV development in our study. Large population-based studies are needed to clarify the aetiology of this common developmental disorder.

CYP17 gene polymorphisms: prevalence and associations with hormone levels and related factors. a HuGE review.

The cytochrome P-450c17alpha (CYP17 ) gene, located on chromosome 10q24.3, encodes the enzyme cytochrome P-450c17alpha, which functions at key branch points in steroid hormone biosynthesis. Three polymorphisms have been described, but only the single base-pair change in the 5'-untranslated region (5'-UTR) has been investigated to any great extent. In single studies, the variant was associated with reduced messenger RNA level in ovarian cells but not with messenger RNA level in breast tissue. Homozygosity for the 5'-UTR variant is most common in East Asian (32%) and Japanese (22%) populations and is less common among White (mainly European and North American (14%)) and Black (mainly African-American (13%)) populations, but selection biases are likely to have affected these frequency estimates. Genotype appears to influence circulating estrogen levels in premenopausal women, while studies of relations with hormone levels in men have produced inconclusive results. However, relatively few studies have been conducted. Seven of 11 retrospective studies suggested a modest association between genotype and age at menarche. Random error in recall of age at menarche is likely to have attenuated this relation. Associations between genotype and postmenopausal estrogen use and bone mass have been observed in single studies. Further investigation of relations between genotype and hormone levels, exogenous hormone use, and markers of hormonal status may advance understanding of hormonally mediated diseases.

Influence of socioeconomic conditions on growth in infancy: the 1921 Aberdeen birth cohort.

OBJECTIVES: To identify environmental influences on infant growth using data from a birth cohort established in 1921. DESIGN: A longitudinal cohort study. SETTING: Aberdeen 1921-22. SUBJECTS: Five hundred and sixteen individuals (263 boys and 253 girls) born in Aberdeen during 1921. Health visitor assessments ranged from two to 40 (47% received at least 10 visits). No records were available for infants who died. Individuals were grouped as those who did not breast feed, those who breast fed initially but not at 6 months, and those who were continuing to breast feed at 6 months. MAIN OUTCOME MEASURE: Rate of weight gain over the 1st year of life. A random effects model was used to identify environmental factors and conditions contributing to rate of weight gain in the 1st year of life. RESULTS: Breast feeding rates were about 80% and 50% at 10 days and 6 months, respectively. Breast fed infants were significantly heavier than bottle fed infants at 28 days but this difference disappeared by 12 months. Significant negative effects on rate of weight gain, independent of initial body weight, were found for overcrowding in family homes and maternal parity, whereas social class had no effect. CONCLUSION: Studies based on historical cohorts that have controlled socioeconomic variables only in terms of social class (derived from parental occupation) may have been subject to residual confounding. Growth in the 1st year of life is likely to reflect a number of environmental influences, some of which may continue to have effects throughout early life and beyond.