Your ovaries normally grow cyst-like structures called follicles each
month. Follicles are little "chemical factories" that produce the
hormones estrogen and progesterone and release an egg when you ovulate.
Sometimes a normal monthly follicle just keeps growing. When that
happens, it becomes known as a functional cyst. This means it started
during the normal function of your menstrual cycle. There are two types
of functional cysts:
-
Follicular
cyst.
Around the midpoint of your menstrual cycle, your brain's pituitary
gland releases a surge of luteinizing hormone (LH), which signals
the follicle holding your egg to release it. When everything goes
according to plan, your egg bursts out of its follicle and begins
its journey down the fallopian tube in search of fertilization. A
follicular cyst begins when the LH surge doesn't occur. The result
is a follicle that doesn't rupture or release its egg. Instead it
grows and turns into a cyst. Follicular cysts are usually harmless,
rarely cause pain and often disappear on their own within two or
three menstrual cycles.
-
Corpus luteum
cyst.
When LH does surge and your egg is released, the ruptured follicle
begins producing large quantities of estrogen and progesterone in
preparation for conception. This changed follicle is now called the
corpus luteum. Sometimes, however, the egg's escape opening seals
off and fluid accumulates inside the follicle, causing the corpus
luteum to expand into a cyst. Although this cyst usually disappears
on its own in a few weeks, it can grow to almost 4 inches in
diameter and has the potential to bleed into itself or twist the
ovary, causing pelvic or abdominal pain. If it fills with blood, the
cyst may rupture, causing internal bleeding and sudden, sharp pain.
The fertility drug clomiphene citrate (Clomid, Serophene), used to
induce ovulation, increases the risk of a corpus luteum cyst
developing after ovulation. These cysts don't prevent or threaten a
resulting pregnancy.
When to seek medical advice
If you experience severe or spasmodic pain in your lower abdomen,
accompanied by fever and vomiting, see your doctor. These signs and
symptoms — or signs and symptoms of shock such as cold, clammy skin,
rapid breathing, and lightheadedness or weakness — indicate an emergency
and require immediate medical attention.
