Dr De-Kun Li, a reproductive and perinatal epidemiologist at Kaiser Permanente's Division of Research in Oakland, California and colleagues, found that over 500 factory workers with higher urine levels of BPA had between two and four times the risk of having poor semen quality, including low sperm count, motility, vitality and concentration, compared with those who had low urine BPA. Previous animal studies have also shown a link between BPA and adverse effects in male reproductive systems in mice and rats.
These findings may also point to problems beyond the male reproductive system: semen quality and male sexual dysfunction could be early signs of diseases that are harder to study, such as cancer or metabolic diseases. Future diagnostic tests for a variety of indications could incorporate an analysis of sperm.
BPA (Bisphenol-A) is found in food and drink cans, plastic bottles, and many other everyday products. Thus, environmental exposure to BPA may be linked to an increase in infertility.
Light drinking during pregnancy: still no increased risk for socioemotional difficulties or cognitive deficits at 5 years of age?
- Yvonne J Kelly1,
- Amanda Sacker2,
- Ron Gray3,
- John Kelly1,
- Dieter Wolke4,
- Jenny Head1,
- Maria A Quigley3
+ Author Affiliations
- 1Department of Epidemiology and Public Health, University College London, London, UK
- 2Institute for Social and Economic Research (ISER), University of Essex, Colchester, UK
- 3National Perinatal Epidemiology Unit, University of Oxford, Headington, Oxford, UK
- 4Department of Psychology and Health Sciences Research Institute, Warwick Medical School, The University of Warwick, Coventry, UK
- Correspondence to Dr Yvonne Kelly, Department of Epidemiology and Public Health, 1–19 Torrington Place, University College London, London WC1E 6BT, UK; firstname.lastname@example.org
- Accepted 25 June 2010
- Published Online First 5 October 2010
Background This study examines the relationship between light drinking during pregnancy and the risk of socioemotional problems and cognitive deficits at age 5 years.
Methods Data from the nationally representative prospective UK Millennium Cohort Study (N=11 513) were used. Participants were grouped according to mothers' reported alcohol consumption during pregnancy: never drinker; not in pregnancy; light; moderate; heavy/binge. At age 5 years the strengths and difficulties questionnaire (SDQ) and British ability scales (BAS) tests were administered during home interviews. Defined clinically relevant cut-offs on the SDQ and standardised scores for the BAS subscales were used.
Results Boys and girls born to light drinkers were less likely to have high total difficulties (for boys 6.6% vs 9.6%, OR=0.67, for girls 4.3% vs 6.2%, OR=0.69) and hyperactivity (for boys 10.1% vs 13.4%, OR=0.73, for girls 5.5% vs 7.6%, OR=0.71) scores compared with those born to mothers in the not-in-pregnancy group. These differences were attenuated on adjustment for confounding and mediating factors. Boys and girls born to light drinkers had higher mean cognitive test scores compared with those born to mothers in the not-in-pregnancy group: for boys, naming vocabulary (58 vs 55), picture similarities (56 vs 55) and pattern construction (52 vs 50), for girls naming vocabulary (58 vs 56) and pattern construction (53 vs 52). Differences remained statistically significant for boys in naming vocabulary and picture similarities.
Conclusions At age 5 years cohort members born to mothers who drank up to 1–2 drinks per week or per occasion during pregnancy were not at increased risk of clinically relevant behavioural difficulties or cognitive deficits compared with children of mothers in the not-in-pregnancy group.