Citation, DOI & article data
The corpus luteum (plural: corpora lutea) is a temporary endocrine structure involved in ovulation and early pregnancy.
At ovulation the follicle ruptures expelling the ovum into the fallopian tube. The remnants of the follicle after ovulation is referred to as the corpus luteum and ranges from 2-5 cm in diameter but involutes as it matures. The corpus luteum produces estrogen and progesterone, maintaining optimum conditions for implantation if the ovum is fertilised:
- fertilised: the corpus luteum continues to produce these hormones and maximizes the chance of implantation into the endometrium; it reaches a maximum size at ~10 weeks and finally resolves at around 16-20 weeks
- not fertilised: the corpus luteum involutes and turns into a corpus albicans by around 2 weeks
In some instances (especially in twin pregnancies), there may be more than one corpus luteum - (e.g. two corpora lutea)
The corpus luteum is a thick walled cyst with characteristic "ring of fire" peripheral vascularity. It usually has a crenulated inner margin and internal echoes.
General considerations include:
adnexal ectopic pregnancy
- ectopic pregnancy is more echogenic than the ovary in 77-88% 5
- corpus luteum is more echogenic than the ovary in ~3% 5
- ovarian neoplasm
History and etymology
The term "corpus luteum" is derived from the Latin meaning "yellow body" where "corpus" means body and "luteum" means yellow. The corpus luteum eventually involutes into the "corpus albicans" ("white body").
- 1. Frates MC, Doubilet PM, Durfee SM et-al. Sonographic and Doppler characteristics of the corpus luteum: can they predict pregnancy outcome? J Ultrasound Med. 2001;20 (8): 821-7. J Ultrasound Med (abstract) - Pubmed citation
- 2. Durfee SM, Frates MC. Sonographic spectrum of the corpus luteum in early pregnancy: gray-scale, color, and pulsed Doppler appearance. J Clin Ultrasound. 1999;27 (2): 55-9. J Clin Ultrasound (link) - Pubmed citation
- 3. Atri M. Ectopic pregnancy versus corpus luteum cyst revisited: best Doppler predictors. J Ultrasound Med. 2003;22 (11): 1181-4. J Ultrasound Med (full text) - Pubmed citation
- 4. Semelka RC. Abdominal-Pelvic MRI. Wiley-Blackwell. (2010) ISBN:0470487755. Read it at Google Books - Find it at Amazon
- 5. Frates MC, Visweswaran A, Laing FC. Comparison of tubal ring and corpus luteum echogenicities: a useful differentiating characteristic. J Ultrasound Med. 2001;20 (1): 27-31. Pubmed citation
- 6. Levine D, Brown DL, Andreotti RF, Benacerraf B, Benson CB, Brewster WR, Coleman B, Depriest P, Doubilet PM, Goldstein SR, Hamper UM, Hecht JL, Horrow M, Hur HC, Marnach M, Patel MD, Platt LD, Puscheck E, Smith-Bindman R. Management of asymptomatic ovarian and other adnexal cysts imaged at US: Society of Radiologists in Ultrasound Consensus Conference Statement. Radiology. 256 (3): 943-54. doi:10.1148/radiol.10100213 - Pubmed