Leucocytes abundant in stroma, migrate through the epithelium into vaginal lumen. Stringy mucous in which are entangled many leucocytes and a few nucleated epithelial cells. Some follicles grow rapidly. Become more vascular, water content increases, organ distends. Contractility more pronounced.
Leucocytes disappear from mucosa.
Endometrial glands hypertrophy. Epithelum thickens, numerous mitoses in inner layers. Old layers of epithelium line the lumen. Leucocytes no longer migrate through the epithelium. Superficial epithelial cells slough off into lumen.