This educational segment provides a detailed histological and endocrinological description of the Corpus Luteum (CL), the ovarian structure that develops from the Graafian follicle after ovulation. Unlike its precursor, which secreted estrogen via granulosa cells, the CL is highly vascular and features steroid-producing luteal cells. These cells contain accumulated steroid hormones, giving the CL its characteristic yellow appearance ("ludum" is Latin for yellow). In the case of pregnancy, the CL becomes significantly large (the Corpus Luteum of Pregnancy), serving as the primary source of progesterone crucial for sustaining gestation, a function primarily stimulated by pituitary Luteinizing Hormone (LH).
The Corpus Luteum: Histology and Function
0:03 Post-Ovulation Development: The Corpus Luteum (CL) develops from the Graafian follicle (which previously secreted estrogen via granulosa cells under FSH/LH influence) after ovulation occurs.
0:40 Active Structure: The CL is an extremely active endocrine structure, differing from the follicle by containing luteal cells rather than granulosa cells.
1:00 Cellular Appearance: The luteal cells are foamy because they contain stored steroid hormones. This steroid content causes the structure to look yellow, which is why it is called the Corpus Luteum ("ludum" is the Latin word for yellow).
1:13 Microscopic Detail: Luteal cells feature round or vacuolar nuclei and granular, slightly foamy cytoplasm. The structure is notably highly vascular, containing many visible blood vessels.
1:35 Size Variation and Hemorrhage: The size of the CL is variable. If pregnancy occurs, it can become very large (up to a third or half of the ovary's volume). Due to its high vascularity, the CL often displays hemorrhage.
2:28 Role in Pregnancy: A large, classic Corpus Luteum is likely a Corpus Luteum of Pregnancy, which acts as the primary producer of progesterone to support the pregnancy.
2:42 Hormonal Regulation: The Corpus Luteum is primarily stimulated by Pituitary Luteinizing Hormone (LH).