An ovarian cyst refers to a fluid-filled sac that forms on or within an ovary. These cysts are common and can occur at any point in a woman’s reproductive life. During pregnancy, the discovery of an ovarian cyst is often an incidental finding during routine prenatal care, such as an ultrasound. While the presence of a cyst might initially cause concern, most ovarian cysts found during pregnancy are benign and do not lead to complications.
Understanding Ovarian Cysts in Pregnancy
Ovarian cysts are sacs that develop on the ovaries, and their formation is closely tied to the menstrual cycle and hormonal changes. In pregnancy, the most frequently encountered type is the corpus luteum cyst. This cyst forms from the follicle that released the egg, and instead of shrinking, it fills with fluid and remains on the ovary. The corpus luteum is essential in early pregnancy as it produces progesterone, a hormone necessary to support the developing fetus until the placenta takes over, typically around 7 to 12 weeks of gestation.
Other types of cysts can also be present or develop during pregnancy. Follicular cysts, another common functional type, arise when a follicle containing an egg fails to rupture and release the egg. Dermoid cysts (also known as teratomas), which contain various bodily tissues like skin, hair, or even teeth, can be present from birth but grow during reproductive years. Endometriomas, often called “chocolate cysts,” can form in women with endometriosis, a condition where uterine lining-like tissue grows outside the uterus.
Detection of Ovarian Cysts in Pregnancy
Ovarian cysts are typically discovered during routine prenatal examinations, most often through an ultrasound scan. The widespread use of obstetric ultrasound, particularly in the first trimester, has significantly increased their incidental detection. During an ultrasound, the size, shape, and contents of any identified cyst are evaluated to determine if it is fluid-filled, solid, or a mixture.
While most cysts are asymptomatic and found incidentally, some may cause symptoms that lead to their discovery. Pelvic pain or pressure can sometimes indicate a cyst’s presence. For the majority of routine cysts, however, their presence is only revealed during a scheduled imaging appointment.
Potential Concerns with Ovarian Cysts During Pregnancy
While most ovarian cysts in pregnancy are harmless, certain potential complications can arise. One concern is ovarian torsion, which occurs when the ovary twists around its blood supply, cutting off blood flow. This condition typically presents with sudden, severe pain and requires immediate medical attention and often surgery. Another potential issue is the rupture of a cyst, which can cause sudden, sharp pain, and sometimes fever, vomiting, or dizziness. While a ruptured cyst usually resolves on its own with pain management, internal bleeding can occur in some instances.
Although rare, there is a possibility of a malignant (cancerous) cyst. Malignancy is more commonly associated with cysts that are larger than 5-6 cm, have solid components, or show suspicious features on imaging. Symptoms like persistent pain, bloating, or changes in bowel habits might be associated with more complex cysts, though these symptoms can also be normal during pregnancy.
Management and Monitoring of Ovarian Cysts in Pregnancy
Management of an ovarian cyst during pregnancy largely depends on its size, characteristics, and whether it is causing symptoms. For most benign-appearing cysts, especially those under 5-6 cm, a “watchful waiting” approach is recommended. This involves close observation, as many functional cysts, particularly corpus luteum cysts, will resolve spontaneously by the second trimester or after delivery.
Follow-up ultrasounds are important to monitor the cyst’s size and appearance, ensuring it does not grow significantly or develop concerning features. If a cyst is large (typically over 5-10 cm), complex, or causes severe symptoms, surgical intervention might be considered. When necessary, surgery is often performed during the second trimester (around 14-23 weeks) to minimize risks, as miscarriage risk is lower and the uterus is not yet too large. Surgical removal can often be done using minimally invasive techniques, such as laparoscopy.
Outlook for Pregnancy with an Ovarian Cyst
For most individuals, an ovarian cyst during pregnancy does not negatively impact pregnancy outcome or delivery method. Many cysts, especially functional ones like corpus luteum cysts, naturally resolve as pregnancy progresses, often by the middle of the second trimester or after childbirth. Even if a cyst persists, it rarely interferes with a vaginal delivery.
The prognosis for both the mother and the baby remains favorable. Close monitoring by healthcare providers ensures any changes or potential complications are identified and managed promptly. This proactive approach allows for a safe and healthy pregnancy journey, with most women experiencing no long-term issues related to the cyst.