Adverse environmental factors in the etiology of free form down syndrome

This paper explores the significance of environmental risk factors in the occurrence of regular form Down syndrome (DS) among the children of mothers under 35 at the time of conception. 100 mothers of children with cytogenetically documented trisomy 21 (DS group) were compared to 100 age-matched mothers of cytogenetically normal children with minor acute illnesses (controls). Respective mean ages were 25.3 (range 17-34) and 24.9 (18-33). The data were accrued by personal interviews using a structured questionnaire, with the following main points of interest: genital disorders (in situ cervical carcinoma, genital herpes, non-specific genital inflammation); systemic diseases (acute febrility states, viral infections, toxoplasma and mycoplasma infections, thyroid dysfunction, diabetes); medicaments use; smoking, drug and alcohol abuse; radiation and chemicals exposure; profession; contraception practice; coital frequency; psychological stress. Fathers' age, profession, health status, smoking habits, and exposure to radiation, drugs or chemicals were also recorded. In spite of some conspicuous differences between the DS and control mothers (higher incidence of nonspecific genital inflammation, more medication at the time of conception, more smokers, more potential professional exposure to chemicals), the group differences were not fully statistically significant (c2-test). Since the exposure of young women (under 35) to known environmental risk factors is not reliably associated with the occurrence of DS in the offspring, a convenient and financially acceptable prenatal screening system would be desirable.