Most ovarian cysts disappear on their own within 6 to 8 weeks, often resolving after just one or two menstrual cycles. But the timeline depends entirely on the type of cyst. Functional cysts, the kind that form as a normal part of ovulation, are temporary by nature. Other types can persist for months, years, or indefinitely without treatment.
Functional Cysts: 1 to 3 Cycles
The most common ovarian cysts are functional cysts, and they come in two varieties. Follicular cysts form when the follicle that normally releases an egg doesn’t open and instead fills with fluid. Corpus luteum cysts develop after the egg is released, when the empty follicle seals shut and accumulates fluid instead of shrinking away. Both types are a byproduct of your normal menstrual cycle, and both tend to resolve without any intervention.
Simple, thin-walled cysts under 5 centimeters typically resolve within 2 to 3 menstrual cycles. Many disappear even faster. If a functional cyst is found incidentally during an ultrasound, your doctor will often recommend waiting and rechecking in 6 to 8 weeks rather than doing anything about it. In most cases, the follow-up ultrasound shows the cyst is already gone.
Cysts That Don’t Resolve on Their Own
Not all ovarian cysts are functional. Several types persist because they aren’t tied to your monthly cycle and have no built-in mechanism for reabsorption.
- Dermoid cysts contain tissue like hair, skin, or teeth because they develop from the cells that produce eggs. They grow slowly and can be present for years before being discovered. They don’t resolve spontaneously.
- Endometriomas form when tissue similar to the uterine lining grows on the ovary, creating a cyst filled with old blood (sometimes called a “chocolate cyst”). These are linked to endometriosis and persist unless surgically removed or managed with hormonal treatment.
- Cystadenomas develop from cells on the outer surface of the ovary. They can grow quite large and don’t disappear on their own.
If an ultrasound shows a cyst with complex features (thick walls, solid areas, internal divisions, or irregular shapes), it’s less likely to be a simple functional cyst and more likely to need monitoring or intervention.
When Size Changes the Timeline
Size plays a significant role in how long a cyst is watched before treatment is considered. In premenopausal women, simple cysts under 5 centimeters are generally left alone and expected to resolve. Simple cysts larger than 7 centimeters typically prompt a referral for possible surgery, because larger cysts are less likely to disappear and carry a higher risk of complications.
Large cysts can cause the ovary to shift position, increasing the chance of ovarian torsion, where the ovary twists on itself and cuts off its own blood supply. Larger cysts are also more likely to rupture. Both situations cause sudden, severe pelvic pain and require emergency care.
Ovarian Cysts After Menopause
Cysts found after menopause follow a different set of rules because functional cysts shouldn’t be forming once ovulation has stopped. That said, small simple cysts in postmenopausal women are more common than many people realize, and most are benign.
Simple, one-sided cysts smaller than 3 centimeters have a very low risk of malignancy and, according to Royal College of Obstetricians and Gynaecologists guidelines, don’t require follow-up at all. Cysts between 3 and 5 centimeters with normal blood markers are typically rechecked in 4 to 6 months. If the cyst stays the same size or shrinks over one year, it’s generally considered safe to stop monitoring. Postmenopausal cysts larger than 5 centimeters usually warrant an urgent gynecology referral, as surgery is more often recommended at that size.
The risk of cancer in simple postmenopausal cysts under 5 centimeters that are one-sided, single-chambered, and have no solid components is less than 1%.
Birth Control Won’t Speed Things Up
A common assumption is that starting hormonal birth control will help an existing cyst go away faster. The evidence doesn’t support this. A review of randomized trials found that oral contraceptives neither increased the likelihood of cyst resolution nor shortened the time it took for cysts to disappear. A functional cyst that’s already formed will resolve on its own timeline regardless of whether you start the pill.
Where birth control does help is in prevention. By suppressing ovulation, hormonal contraceptives reduce the chance of new functional cysts forming in the future. So if you’ve had recurrent cysts, birth control may be worth discussing, but it won’t shrink the one you have now.
What the Waiting Period Looks Like
If you’ve been told you have a cyst and need to wait for a follow-up ultrasound, that period can feel frustrating, especially if you’re experiencing symptoms. Functional cysts can cause a dull ache or feeling of pressure on one side of your pelvis, bloating, or mild pain during sex. These symptoms typically fade as the cyst shrinks.
During the waiting period, there are a few signs that warrant immediate medical attention: sudden, severe pelvic or abdominal pain, pain accompanied by fever or vomiting, and symptoms of shock like cold or clammy skin, rapid breathing, or lightheadedness. These can indicate a ruptured cyst or ovarian torsion, both of which need emergency treatment.
For the majority of cysts, though, the follow-up ultrasound at 6 to 8 weeks confirms what your doctor expected: the cyst is gone, and no further action is needed.