title: Opioids, pregnancy and the disappearance of headache.
mesh_terms: D004723:Endorphins / Q000502:physiology*; D005260:Female; D006261:Headache / Q000503:physiopathology*; D006801:Humans; D011247:Pregnancy; D011248:Pregnancy Complications / Q000503:physiopathology*; D011262:Pregnancy Trimester, Second; D012075:Remission, Spontaneous
chemical_list: D004723:Endorphins