title: Letter: H.P.L. and twins.
mesh_terms: D005260:Female; D005313:Fetal Death / Q000097:blood; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D010928:Placental Lactogen / Q000097:blood*; D011247:Pregnancy; D011272:Pregnancy, Multiple; D014427:Twins
chemical_list: D010928:Placental Lactogen