Ovarian cysts are fluid-filled sacs that are found on or inside the ovaries. While the majority of cysts are harmless, some ovarian cysts affect fertility by way of the illnesses that cause the cysts. They are very common with many women developing them at some point in their life. Most are harmless and cause no symptoms or pain, which is why they usually go undetected, disappearing over time without the need for medical intervention as such ovarian cysts are often only found during routine pelvic examinations or ultrasounds.
Some of the common signs and symptoms of ovarian cysts include bloating, needing to urinate more often, pelvic pressure or pain, abnormal vaginal bleeding, sudden, severe pain in the abdomen, dizziness, weakness, or feeling faint and fast breathing. Although it is rare, a cyst may rupture causing sudden pain, in which case you should go to the doctor immediately. While it’s not typical for ovarian cysts to affect fertility, larger or multiple cysts can have other side effects or symptoms, such as if your cyst(s) don’t go away on their own after a few months and continue to grow, or cause you pain, your doctor might recommend surgery to remove it. With larger ovarian cysts, there is the concern for a rare condition of twisting of the ovary, called ovarian torsion, which if not corrected promptly with surgery, can lead to loss of an ovary. Alternative treatments for benign cysts include hormonal birth control — such as the pill, vaginal ring, shot, or patch — which prevent ovulation and lower your chances of getting more cysts.
Malignant (cancerous) cysts are very rare in young women. Not all ovarian cysts affect fertility. In fact, functional cysts sometimes form as a by-product of the regular process of ovulation. Each month (usually), an egg grows in an ovarian follicle, matures, and breaks out of the follicle.
Two types of cysts are commonly formed out of ovulation:
Follicular cysts form when, instead of breaking open to release the egg, the follicle stays intact and the cyst continues to grow.
Corpus luteum cysts, or luteal cysts, sometimes form after ovulation. Normally, once the egg has broken free, the follicle shrinks into a mass of cells known as the corpus luteum, which produces hormones to prepare for the next cycle.
Luteal cysts form when, instead of shrinking, the follicle closes again itself and fluid builds up inside. Both of these cysts are typically harmless and disappear within 1–3 months without treatment. And for pregnant women, corpus luteum cysts are actually important: they produce progesterone, a hormone that’s essential for the first 8–10 weeks of pregnancy.
Endometriosis is one example of an illness that can cause ovarian cysts that affects fertility. Endometriosis occurs when endometrial tissue — the lining of the uterus —begins to grow in other places, like on the outside of the uterus or the fallopian tubes. One result of endometriosis is ovarian cysts known as “endometriomas,” formed when this tissue grows in the ovaries. Endometriomas can range in size from less than an inch to over 6 inches and are often filled with dark blood. Secondly, polycystic ovary syndrome (PCOS), a hormone imbalance that causes many tiny ovarian cysts, affects fertility at a higher rate than almost any other condition (besides age). In PCOS, the eggs that begin to develop during the ovulation cycle never mature enough to prompt ovulation, so none of them is released from the ovary. The immature follicles, each containing an immature egg, then cause the ovary to become “polycystic,” filled with these tiny cysts.
The chronic lack of ovulation alters the levels of hormones that play an important role in the ovulation process, and PCOS is often associated with higher levels of male hormones known as “androgens.” It’s not the ovarian cysts themselves that affect fertility in cases of PCOS — it’s a fact that women with PCOS don’t ovulate, and ovulation is essential for getting pregnant naturally. In other cases, a different type of cyst can form — these are known as ‘pathological cysts’ and have several types.
Dermoid cysts are those which contain unwanted tissue such as hair, skin or teeth and can grow rather large.
Cystadenomas are those which develop from cells covering the outer layer of the ovary and can be filled with watery liquid or mucous. Both of these types may require surgical removal of ovarian cysts. This surgery should not, however, affect fertility, unless the doctor removes an ovary. This is rare though and only occurs where cysts are extremely large, complex or cancerous. It is highly recommended that surgery is carried out before pregnancy, so as to avoid complications.
(The author is a consultant in reproductive medicine.)