[Reproductive behavior and Down syndrome]

Coital rates and contraception practice were investigated in mothers of 160 newborns with Down syndrome (DS) in comparison with the same aged (+/- 1 year) mothers of 160 healthy newborns. A considerable lowering of sexual activity is typical for parents, especially young ones, of children with DS. No relationship between parental sexual behavior and maternal hormonal dysfunction was found. Study on children sex ratio (SR) in relation to parental sexual activity revealed that the prevalence of boys in the DS children was due to the excess of boys (SR = 1.85) in the small group of children from sexually active couples. These data are discussed as evidence of association of a high coital rate with chromosome malsegregation in spermatogenesis.

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