Abstract
Objectives
Although there is concern that occupational exposures in some nursing professions may confer reproductive risks, there are few relevant studies. Our objective is to determine if a cohort of female registered nurses (RN) from British Columbia (BC), in comparison to BC women in general, have elevated rates of congenital anomalies, stillbirths, low birth weight, or prematurity in their offspring.
Methods
A cohort of RNs from BC was linked to Vital Statistics birth records and the BC Health Status Registry (HSR) between the years 1986 and 2000. The RN offspring cohort included 23,222 births. For each outcome, odds ratios (OR) with 95% confidence intervals (CI) were determined by comparing rates in the nurses’ cohort with the rates in the general population standardized for the year of birth.
Results
Apart from chromosomal anomalies, for each of the ICD-9 congenital anomaly categories there were fewer congenital anomalies than expected, resulting in an overall prevalence of congenital anomaly cases (with at least one anomaly) that was significantly lower in the RN cohort (1,567 observed vs. 1,846 expected; OR 0.84, 95% CI 0.78-0.90) in comparison to the general population. Low birth weight (1,138 observed vs. 1,260 expected; OR 0.90, 95% CI 0.83-0.98) was also significantly lower, while prevalence of prematurity and stillbirths were not significantly different than among the general population.
Conclusion
Offspring of RNs in BC had a lower prevalence of congenital anomalies and low birth weight compared to the rates found among the general population. Further studies are underway to determine if subpopulations within the RN cohort are at risk.
Key words: Congenital abnormalities, pregnancy outcomes, birth weight, nurses
Résumé
Objectifs
On craint que les expositions professionnelles dans certains métiers des soins infirmiers présentent des risques génésiques, mais il existe peu d’études sur ce sujet. Nous avons voulu déterminer si la progéniture d’une cohorte d’infirmières autorisées de la Colombie-Britannique (C.-B.), comparativement aux Britanno-Colombiennes en général, présentait des taux élevés d’anomalies congénitales, de mortinatalité, d’insuffisance de poids à la naissance ou de prématurité.
Méthode
Nous avons maillé une cohorte d’infirmières autorisées de la C.-B. avec les dossiers de naissance et le registre de l’état de santé de cette province entre 1986 et 2000. La cohorte d’enfants d’infirmières autorisées comptait 23 222 naissances. Pour chaque résultat, nous avons calculé les rapports de cotes (RC) avec intervalles de confiance (IC) de 95% en comparant les taux dans la cohorte des infirmières aux taux dans la population générale, normalisés pour l’année de naissance.
Résultats
À l’exception des anomalies chromosomiques, il y a eu moins d’anomalies que prévu dans chacune des catégories d’anomalies congénitales de la CIM-9. La prévalence globale des cas d’anomalies congénitales (avec au moins une anomalie) était significativement moins élevée dans la cohorte des infirmières autorisées (1567 cas observés c. 1846 cas attendus; RC = 0,84, IC 95% = 0,78-0,90) que dans la population générale. L’insuffisance de poids à la naissance (1138 cas observés c. 1260 cas attendus; RC = 0,90, IC 95% = 0,83-0,98) était aussi significativement moins élevée, tandis que la prévalence de la prématurité et de la mortinatalité n’était pas significativement différente de celle dans la population générale.
Conclusion
La progéniture des infirmières autorisées en C.-B. a une prévalence plus faible d’anomalies congénitales et d’insuffisance de poids à la naissance que dans la population générale. D’autres études sont en cours pour déterminer si certaines sous-populations de la cohorte des infirmières autorisées sont à risque.
Mots clés: anomalies congénitales, pronostic de la grossesse, poids de naissance, infirmières et infirmiers
Footnotes
Conflict of Interest: None to declare.
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