📖 Corpus Luteum

In Detail

After ovulation, the empty follicle transforms into the corpus luteum, which secretes progesterone for approximately 12-14 days (the luteal phase). If pregnancy occurs, hCG from the embryo signals the corpus luteum to continue producing progesterone until the placenta takes over (around weeks 8-12). If no pregnancy occurs, the corpus luteum degenerates, progesterone drops, and menstruation begins.