Complications & Concerns Corpus Luteum Cysts During Pregnancy By Robin Elise Weiss, PhD, MPH twitter linkedin Robin Elise Weiss, PhD, MPH is a professor, author, childbirth and postpartum educator, certified doula, and lactation counselor. Learn about our editorial process Robin Elise Weiss, PhD, MPH Medically reviewed by Medically reviewed by Brian Levine, MD, MS, FACOG on January 28, 2019 Brian Levine, MD, MS, is board-certified in obstetrics and gynecology as well as in reproductive endocrinology and infertility. Learn about our Review Board Brian Levine, MD, MS, FACOG Updated on February 18, 2020 Print Lumi Images / Romulic-Stojcic / Getty Images Table of Contents View All Overview Who Gets Them Symptoms Diagnosis Treatment Follow-Up/Recurrence During the second half of the menstrual cycle, immediately following ovulation, the empty ovarian follicle forms the corpus luteum. The corpus luteum releases estrogen as well as progesterone, which readies the uterus for implantation. If conception has occurred, the placenta will take over the function of progesterone production at around 12 weeks gestation. Overview Sometimes, a small fluid-filled sac known as a corpus luteal cyst, or corpus luteum cyst, can develop on the ovary during the first trimester of pregnancy. Corpus luteal cysts are a type of functional cyst. While they vary in size, corpus luteal cysts are usually between 2 and 6 centimeters. Though they are not usually not any cause for concern, these cysts can lead to complications, though not typically related to pregnancy itself. Risk Factors Any women can get corpus luteal cysts, though they are more likely to develop in women taking medication to induce ovulation, like Clomid (clomiphene). These medications are usually prescribed by a doctor or midwife for women experiencing fertility problems, and for those with polycystic ovary syndrome (PCOS). It's important to remember that since the corpus luteum is a normal part of the menstrual cycle, the type of functional ovarian cyst associated with them can also develop when you are not pregnant. You can also develop one even if you are not taking, or have never taken, medication to treat infertility. Symptoms Some women will notice one-sided pain during their cycle. The pain may be worrisome, especially if they are sexually active and concerned about the possibility of an ectopic or tubal pregnancy. This may prompt a visit to a doctor or midwife. But in many cases, women who have a corpus luteal cyst do not experience any pain and may not even realize they have developed one. As a corpus luteal cyst will typically resolve on its own after a few menstrual cycles, and most women won't even realize it was ever there. Diagnosis Corpus luteal cysts are typically diagnosed with an ultrasound. However, it may be a different type of ultrasound from the one most women expect. Cysts tend to be easier to see when an internal ultrasound, or a transvaginal ultrasound, is used. While ultrasound may be ordered if you present symptoms, cysts are often found during a routine ultrasound for other purposes, both in women who are pregnant and those who are not. (There are more opportunities to spot a corpus luteal cyst in a woman who's expecting, however, simply because she's having routine imaging as part of her prenatal care.) Treatment A corpus luteal cyst is usually not a cause for concern. The cysts do not typically cause any complications during pregnancy, especially when they're discovered during the first trimester. If the cyst is potentially malignant, meaning it could grow or worsen, surgery may be required so as to avoid the risk of miscarriage. The most common symptom is a slight "twinge" of pain or mild tenderness. If the cyst is causing pain, your doctor or midwife may prescribe pelvic rest or pain medications. In most cases, a corpus luteal cyst will resolve on its own. Occasionally the cyst will rupture. The pain may increase when this happens but subside quickly, and pain medication and rest may be indicated. Less frequently, a corpus luteal cyst can cause the ovary to twist (torsion). This can be very painful and may require surgery to prevent further injury of the ovary. Follow-Up and Recurrence Your doctor or midwife may want you to have another ultrasound to check on the cyst if you continue to have symptoms. Otherwise, unless medical treatment is required, no follow-up will be needed after you have been diagnosed with a corpus luteal cyst. If you have had a corpus luteal cyst in one pregnancy it does not necessarily mean you will develop one in another pregnancy. If you do develop cysts in subsequent pregnancies, they may or may not cause pain. Was this page helpful? Thanks for your feedback! Get diet and wellness tips to help your kids stay healthy and happy. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Kumar P, Magon N. Hormones in pregnancy. Niger Med J. 2012;53(4):179–183. doi:10.4103/0300-1652.107549 Ross E, Fortin C. Ovarian Cysts. Cleveland Clinic. August 2016. Legro RS, Brzyski RG, Diamond MP, et al. Letrozole versus clomiphene for infertility in the polycystic ovary syndrome. N Engl J Med. 2014;371(2):119–129. doi:10.1056/NEJMoa1313517 Sivalingam VN, Duncan WC, Kirk E, Shephard LA, Horne AW. Diagnosis and management of ectopic pregnancy. J Fam Plann Reprod Health Care. 2011;37(4):231–240. doi:10.1136/jfprhc-2011-0073 Sayasneh A, Ekechi C, Ferrara L, et al. The characteristic ultrasound features of specific types of ovarian pathology (review). Int J Oncol. 2015;46(2):445–458. doi:10.3892/ijo.2014.2764 Hakoun AM, AbouAl-Shaar I, Zaza KJ, Abou-Al-Shaar H, A Salloum MN. Adnexal masses in pregnancy: An updated review. Avicenna J Med. 2017;7(4):153–157. doi:10.4103/ajm.AJM_22_17 Lee MS, Moon MH, Woo H, Sung CK, Jeon HW, Lee TS. Ruptured corpus luteal cyst: Prediction of clinical outcomes with CT. Korean J Radiol. 2017;18(4):607–614. doi:10.3348/kjr.2017.18.4.607 Additional Reading Ovarian Cysts. U.S. Department of Health and Human Services. 2018. Bonde AA, Korngold EK, Foster BR, et al. Radiological appearances of corpus luteum cysts and their imaging mimics. Abdom Radiol (NY). 2016;41(11):2270-2282. doi:10.1007/s00261-016-0780-1 Cleveland Clinic. Female Reproductive System. Reviewed January 19, 2019. Gabbe S, Niebyl J, Simpson J. Obstetrics: Normal And Problem Pregnancies. 6th ed. New York: Elsevier Saunders; 2012. Huang C, Hong MK, Ding DC. A review of ovary torsion. Ci Ji Yi Xue Za Zhi. 2017;29(3):143–147. doi:10.4103/tcmj.tcmj_55_17 The American College of Obstetricians and Gynecologists. Ovarian Cysts - ACOG. 2017.