Ask An Expert

A: A corpus luteum is normal in the first 12 weeks - in fact, it's necessary in that it's the structure that manufactures progesterone to maintain the pregnancy during the first trimester. A corpus luteal cyst is just an exaggerated corpus luteum, and it is completely normal. If it were to be removed by surgery, you would miscarry, so it's best that it remain, of course. It'll fizzle out on its own by about 10-12 weeks, so fret not. By the time it's gone, your placenta will be making enough progesterone. Sometimes a cyst can get very large, causing pain. If it gets too big, it can twist on itself -called "torsion," which can endanger your ovary. But in 22 years of practice, I've never seen torsion from a corpus luteal cyst. Sounds to me like you're normal. Enjoy your pregnancy.