Immunohistochemical localization of CRH-R1 and CRH-R2 in the human cervix. CRH-R1 in the cervical epithelium at (A) non-pregnant state, (B) term not in labor, (C) term in labor. CRH-R2 in the (A) cervical epithelium at non-pregnant state, (B) cervical epithelium and extracellular matrix at term not in labor cervix, (C) extracellular matrix at term in labor cervix. These samples were fixed in a 4% formaldehyde solution for a maximum of 24 hours and subsequently dehydrated in 70% ethanol. The brown color represents positive staining. The magnification is 1 × 200.