Ovarian cysts are far more common in young women than most people realize. In fact, many are a completely normal part of how the ovaries function—and most resolve without any treatment at all. However, understanding what causes ovarian cysts in young females is essential for distinguishing between harmless functional cysts and those that might require medical attention. Most often, these cysts are a byproduct of the menstrual cycle, occurring when a follicle fails to release an egg or doesn’t dissolve properly after the egg is released.
In young females, ovarian cysts most commonly develop as part of the normal menstrual cycle (functional cysts), or as a result of PCOS, endometriosis, or hormonal imbalances. In the vast majority of cases, they are benign and resolve on their own within a few months.
What Is an Ovarian Cyst?
An ovarian cyst is a fluid-filled sac on or within the ovary. They range in size from a small pea to a grapefruit. Most cause no symptoms and are discovered incidentally during a pelvic ultrasound.
The Most Common Cause: Functional Cysts
These are the most frequent type – and they’re not really a “disease” at all. They’re a normal ovarian function that’s gone slightly off-script.
Follicular Cysts
Each month, an egg develops inside a small fluid-filled sac called a follicle. Normally, the follicle ruptures and releases the egg at ovulation. If the follicle doesn’t rupture, it continues to grow – forming a follicular cyst.
These are extremely common in young women. Most shrink on their own within 1-3 menstrual cycles and require no treatment.
Corpus Luteum Cysts
After the follicle releases an egg, it transforms into a structure called the corpus luteum, which produces progesterone. If the corpus luteum seals up and fills with fluid, it forms a cyst.
These are also very common and usually resolve on their own, though they can sometimes rupture or twist – causing sudden, significant pain.
Polycystic Ovary Syndrome (PCOS)
PCOS is one of the most common hormonal conditions in young women, affecting an estimated 1 in 10. In PCOS, the ovaries produce excess androgens (male hormones), disrupting normal ovulation. Multiple small, immature follicles form but don’t fully develop – creating the “polycystic” appearance on ultrasound.
These aren’t true cysts – they’re immature follicles – but they appear as numerous small, round structures surrounding the ovary.
PCOS cysts are associated with:
- Irregular or absent periods
- Excess hair growth (hirsutism)
- Acne, particularly on the jawline
- Weight gain, especially around the abdomen
- Elevated androgens on blood tests
Endometriosis (Endometriomas)
When endometriosis (uterine lining tissue growing outside the uterus) affects the ovary, it creates what’s called an endometrioma – sometimes called a “chocolate cyst” because the old blood inside appears dark brown.
These are significant because:
- They can be painful, especially during periods
- They can affect fertility
- They don’t resolve on their own
- They require medical or surgical management
Young women with severe menstrual cramps, pelvic pain between periods, or pain during sex should be investigated for endometriosis.
Dermoid Cysts (Mature Cystic Teratomas)
These are a type of benign tumor that forms from the cell types that create eggs. They can contain tissue like hair, skin, teeth, or fat – which sounds alarming, but they’re almost always benign. They’re most commonly found in women of reproductive age.
Dermoid cysts don’t typically cause symptoms unless they grow large or twist (ovarian torsion). They require surgical removal.
Cystadenomas
Ovarian cystadenomas are cysts that develop from the surface of the ovary. They can grow quite large. There are two types:
- Serous cystadenomas – filled with watery fluid
- Mucinous cystadenomas – filled with mucus-like fluid, can become very large
These are benign but typically require monitoring or surgical removal depending on size.
Hormonal Causes in Young Females
Young women are particularly prone to functional cysts when hormonal fluctuations are more pronounced:
|
Hormonal Factor |
Why It Leads to Cysts |
|---|---|
|
Irregular cycles |
Unpredictable ovulation increases functional cyst risk |
|
Hormonal contraceptive changes |
Starting or stopping the pill disrupts the ovulatory cycle temporarily |
|
High stress |
Cortisol disrupts the HPO axis, impairing ovulation |
|
Hypothyroidism |
Low thyroid function disrupts reproductive hormones |
|
Insulin resistance |
Drives androgen excess and anovulation (as in PCOS) |
|
Puberty |
Hormonal axis still calibrating; functional cysts are more frequent |
Symptoms – When Cysts Make Themselves Known
Many cysts cause no symptoms. Those that do may cause:
- Dull aching or fullness on one side of the lower abdomen
- Bloating
- Pelvic pain that’s worse during menstruation
- Pain during sex
- Irregular periods
Symptoms requiring urgent attention:
- Sudden, severe, sharp pelvic pain (may indicate rupture or torsion)
- Pain with fever and vomiting (infection)
- Dizziness or fainting alongside pain
Diagnosis
Ovarian cysts are usually found and characterized by:
- Pelvic ultrasound – the primary diagnostic tool; identifies size, type, and characteristics
- Blood tests – CA-125 (tumor marker; not diagnostic alone but used in conjunction), hormone panels, thyroid function
- Laparoscopy – surgical procedure used if diagnosis is unclear or treatment is needed
Treatment Depends on the Type
|
Cyst Type |
Typical Management |
|---|---|
|
Functional cyst |
Watchful waiting; most resolve in 1-3 months |
|
PCOS |
Lifestyle, hormonal therapy, insulin-sensitizing medications |
|
Endometrioma |
Hormonal suppression or surgery |
|
Dermoid cyst |
Surgical removal |
|
Cystadenoma |
Monitoring; surgery if large |
The oral contraceptive pill is sometimes used to regulate cycles and prevent new functional cysts, though it does not shrink existing ones.
When to See a Doctor
See a gynecologist if:
- You have persistent one-sided pelvic pain
- Your periods have become very irregular or very painful
- A cyst has already been identified and isn’t resolving
- You have other signs of PCOS or endometriosis
Go to the ER if you have sudden, severe pelvic pain – this could indicate a ruptured cyst or ovarian torsion (twisting of the ovary on its blood supply), both of which need prompt evaluation.
Bottom Line
In young females, ovarian cysts are most often a byproduct of normal ovulation – and they usually resolve without any intervention. The more important causes to identify are PCOS, endometriosis, and dermoid cysts, which don’t go away on their own and can affect fertility and quality of life if left unmanaged. Regular gynecological checkups and prompt investigation of pelvic pain are the best tools you have.
