Chances are, you don’t give a lot of thought to your ovaries on a day-to-day basis — you do your job and they do theirs, nestled in your pelvis, popping out eggs. Of course, there are two notable exceptions to this rule, times when you actually might need to pay quite a lot of attention to your ovaries: when you’re trying to conceive and when you’ve developed a painful ovarian cyst.

Cysts are scary-sounding (especially if you’ve heard about them bursting or rupturing), but in reality, most ovarian cysts aren’t a big deal unless they’re causing you pain or discomfort. Here’s what you need to know about ovarian cysts, including when — and if — you should actually worry about them.

In people who are regularly ovulating, the ovaries create cysts every single month, as part of the natural ovulation process. These fluid-filled cysts, called follicular cysts, appear and disappear with your cycle, swelling up before the release of the egg (during the follicular phase of the menstrual cycle) and then turning into a different type of cyst (the corpus luteum) just after you ovulate. The corpus luteum is the endocrine body that produces progesterone in the second half of the cycle (in preparation for a pregnancy), but if there’s no developing embryo, it will die and become reabsorbed before menstruation. These cysts are normal and functional. You generally won’t notice them or feel them.

What about those other types of cysts? There are a few different kinds of pathological cysts, says Chloë Lubell, CNM, MSN, WHNP, a New York City-based nurse midwife and nurse practitioner who blogs at The Midwife Is In. These include cystadenomas (non-cancerous growths on the ovary which may cause pain in the abdomen, but are generally benign cysts), endometriomas (growth of endometrial tissue, aka the lining of the uterus, on the ovaries, which can be painful and affect fertility — this is the kind of cyst that Lena Dunham was hospitalized for in 2016), dermoid cysts (usually benign cysts full of tissues like hair or teeth, which are only a problem if they rupture), and cancerous masses. Still, it’s important to understand that the majority of cysts that can develop on the ovaries are totally harmless. Only about 8% of premenopausal women will develop a significant cyst in their lifetime, according to the Cleveland Clinic Journal of Medicine.

These pathological cysts can sometimes burst or rupture, usually causing sudden, sharp pain and/or bleeding, and sometimes nausea. The medical community doesn’t exactly know what makes some cysts break open, although sometimes it happens during sexual activity or exercise. Treatments vary, but occasionally surgery or pain medication is required, especially if the cyst was an endometrioma.

You’ve probably also heard about PCOS in relation to ovarian cysts. Polycystic ovarian syndrome is a condition that often includes cysts on the ovaries (hence the name!). People with PCOS often have irregular periods and lots of body and facial hair, as well as multiple cysts on the ovaries (which are seen via ultrasounds). But the issue isn’t caused by the cysts — the cysts are a symptom of a hormonal imbalance. PCOS cysts usually don’t cause pain.

Lubell explains, “Since cysts are almost always benign, the only time to worry about a cyst is when it is causing you discomfort. There are three times that cysts cause discomfort: when they are large, just from pressing on other things in the abdomen (which usually feels like vague, non-specific abdominal pain that isn’t caused by something else), when they rupture (a sharp, intense pain that may or may not go away), or if they get so big and heavy that they cause the ovary to twist, called ovarian torsion (sudden intense pain on one side that radiates outward, increasing in severity over time, often including nausea and vomiting as well as frequent urge to pee).”

If you suspect you have cysts (through pain or discomfort), talk to your doctor, nurse practitioner, or midwife.They can, Lubell says, do a ”bi-manual exam, which is when the provider inserts two fingers of one hand inside the vagina and presses down on the abdomen with the other hand to check for cysts in the pelvis. If they find anything abnormal, they will send you for an ultrasound.”

Even if you find you do have a cyst at some point, there’s no reason to panic. Lubell advises, “Most of the time, if someone notices a cyst on an unrelated ultrasound it probably doesn’t mean anything, so don’t stress! If you have been diagnosed with cysts, you should only worry about it if you have specific symptoms. Otherwise, the cysts can just hang out there, taking up space but not causing you any harm. Treatment is to treat the symptoms, not to try to get rid of the cysts.”

Carrie Murphy is a freelance writer and doula in Albuquerque, NM. Read more on her website, carrie-murphy.com.