title: Spina bifida and the sex ratio.
mesh_terms: D000022:Abortion, Spontaneous; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D011247:Pregnancy; D012744:Sex Ratio; D016136:Spina Bifida Occulta / Q000235:genetics*; D014960:X Chromosome