title: Letter: two-hour plasma estrogen assay.
mesh_terms: D004964:Estriol / Q000097:blood*; D004967:Estrogens / Q000097:blood*; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis; D005865:Gestational Age; D006801:Humans; D008722:Methods; D011247:Pregnancy; D011863:Radioimmunoassay; D013997:Time Factors
chemical_list: D004967:Estrogens; D004964:Estriol