Down syndrome is not increased in offspring of natural family planning users (case control analysis)
Castilla
E E
EE
Simpson
J L
JL
Queenan
J T
JT
D016022:Case-Control Studies; D003267:Contraception / Q000009:adverse effects; D004314:Down Syndrome / Q000209:etiology*; D005193:Family Planning Services; D005260:Female; D006801:Humans; D008297:Male