title: Letter: Human placental lactogen in screening for multiple pregnancies.
mesh_terms: D005260:Female; D005865:Gestational Age; D006801:Humans; D007752:Obstetric Labor, Premature / Q000517:prevention & control; D010928:Placental Lactogen / Q000097:blood*; D011247:Pregnancy; D011272:Pregnancy, Multiple; D011296:Prenatal Diagnosis; D011863:Radioimmunoassay; D014427:Twins; D014463:Ultrasonography
chemical_list: D010928:Placental Lactogen