• The pool chlorine hypothesis and asthma among boys.

      Cotter, A; Ryan, C A; Department of Paediatrics and Child Health, UCC, Cork University Maternity, Hospital, Wilton, Cork. (2012-01-31)
      Swimming pool sanitation has largely been concerned with the microbiological quality of pool water, which is normally treated using a number of chlorine products. Recent studies have pointed to the potential hazards of chlorine by-products to the respiratory epithelium, particularly in indoor, poorly ventilated, pools. The aim of our study was to elucidate whether chronic exposure to indoor chlorinated swimming pools was associated with an increased likelihood of the development of asthma in boys. METHODS: The subjects were boys aged between 6 and 12 years. Data was collected by means of parental responses to a standardized asthma questionnaire (ISAAC: International Study of Asthma and Allergies in Childhood), supplemented with additional questions regarding frequency of attendance, number of years attendance, whether the child is a swimming team member. The questionnaire return rate was 71/% (n = 121). 23 boys were excluded on the basis that they had asthma before they started swimming (n = 97). There was a significant association between number of years a boy had been swimming and the likelihood of wheezing in the last 12 months (p = 0.009; OR = 1.351; 95% CI = 1.077-1.693) and diagnosed asthma (p = 0.046; OR = 1.299; 95% CI = 1.004-1.506). The greater the number the number of years a boy had been attending an indoor, chlorinated pool, the greater the likelihood of wheezing in the last 12 months or "had asthma". Age, parental smoking habits and being a swimming team member had no association with any of the asthma variables examined. Swimming pool attendance may be a risk factor in asthma in boys.
    • Risk of affective disorders following prenatal exposure to severe life events: a Danish population-based cohort study.

      Khashan, Ali S; McNamee, Roseanne; Henriksen, Tine B; Pedersen, Marianne G; Kenny, Louise C; Abel, Kathryn M; Mortensen, Preben B; Anu Research Centre, Department of Obstetrics and Gynecology, University College , Cork, Cork University Maternity Hospital, Cork, Ireland. a.khashan@ucc.ie (2012-01-31)
      OBJECTIVE: To examine the effect of prenatal exposure to severe life events on risk of affective disorders in the offspring. METHODS: In a cohort of 1.1 million Danish births from May 1978 until December 1997, mothers were considered exposed if one (or more) of their close relatives died or was diagnosed with serious illness up to 6 months before conception or during pregnancy. Offspring were followed up from their 10th birthday until their death, migration, onset of affective disorder or 31 December 2007; hospital admissions were identified by linkage to the Central Psychiatric Register. Log-linear Poisson regression was used for data analysis. RESULTS: The risk of affective disorders was increased in male offspring whose mothers were exposed to severe life events during the second trimester (adjusted RR 1.55 [95% CI 1.05-2.28]). There was an increased risk of male offspring affective disorders in relation to maternal exposure to death of a relative in the second trimester (adjusted RR 1.74 [95% CI 1.06-2.84]) or serious illness in a relative before pregnancy (adjusted RR 1.44 [95% CI 1.02-2.05]). There was no evidence for an association between prenatal exposure to severe life events and risk of female offspring affective disorders. CONCLUSIONS: Our population-based study suggests that prenatal maternal exposure to severe life events may increase the risk of affective disorders in male offspring. These findings are consistent with studies of populations exposed to famine and earthquake disasters which indicate that prenatal environment may influence the neurodevelopment of the unborn child.
    • Secondary recurrent miscarriage is associated with previous male birth.

      Ooi, Poh Veh; Russell, Noirin; O'Donoghue, Keelin; Anu Research Centre, Department of Obstetrics and Gynaecology, University College, Cork, Cork University Maternity Hospital, Wilton, Cork, Ireland. (2012-01-31)
      Secondary recurrent miscarriage (RM) is defined as three or more consecutive pregnancy losses after delivery of a viable infant. Previous reports suggest that a firstborn male child is associated with less favourable subsequent reproductive potential, possibly due to maternal immunisation against male-specific minor histocompatibility antigens. In a retrospective cohort study of 85 cases of secondary RM we aimed to determine if secondary RM was associated with (i) gender of previous child, maternal age, or duration of miscarriage history, and (ii) increased risk of pregnancy complications. Fifty-three women (62.0%; 53/85) gave birth to a male child prior to RM compared to 32 (38.0%; 32/85) who gave birth to a female child (p=0.002). The majority (91.7%; 78/85) had uncomplicated, term deliveries and normal birth weight neonates, with one quarter of the women previously delivered by Caesarean section. All had routine RM investigations and 19.0% (16/85) had an abnormal result. Fifty-seven women conceived again and 33.3% (19/57) miscarried, but there was no significant difference in failure rates between those with a previous male or female child (13/32 vs. 6/25, p=0.2). When patients with abnormal results were excluded, or when women with only one previous child were considered, there was still no difference in these rates. A previous male birth may be associated with an increased risk of secondary RM but numbers preclude concluding whether this increases recurrence risk. The suggested association with previous male birth provides a basis for further investigations at a molecular level.
    • Secondary recurrent miscarriage is associated with previous male birth.

      Ooi, Poh Veh; Russell, Noirin; O'Donoghue, Keelin; Anu Research Centre, Department of Obstetrics and Gynaecology, University College Cork, Cork University Maternity Hospital, Wilton, Cork, Ireland. (2011-01)
      Secondary recurrent miscarriage (RM) is defined as three or more consecutive pregnancy losses after delivery of a viable infant. Previous reports suggest that a firstborn male child is associated with less favourable subsequent reproductive potential, possibly due to maternal immunisation against male-specific minor histocompatibility antigens. In a retrospective cohort study of 85 cases of secondary RM we aimed to determine if secondary RM was associated with (i) gender of previous child, maternal age, or duration of miscarriage history, and (ii) increased risk of pregnancy complications. Fifty-three women (62.0%; 53/85) gave birth to a male child prior to RM compared to 32 (38.0%; 32/85) who gave birth to a female child (p=0.002). The majority (91.7%; 78/85) had uncomplicated, term deliveries and normal birth weight neonates, with one quarter of the women previously delivered by Caesarean section. All had routine RM investigations and 19.0% (16/85) had an abnormal result. Fifty-seven women conceived again and 33.3% (19/57) miscarried, but there was no significant difference in failure rates between those with a previous male or female child (13/32 vs. 6/25, p=0.2). When patients with abnormal results were excluded, or when women with only one previous child were considered, there was still no difference in these rates. A previous male birth may be associated with an increased risk of secondary RM but numbers preclude concluding whether this increases recurrence risk. The suggested association with previous male birth provides a basis for further investigations at a molecular level.