An ovarian cyst is a fluid-filled sac that develops on or within an ovary. Most ovarian cysts are harmless byproducts of the normal menstrual cycle and do not prevent conception. However, the effect on pregnancy depends entirely on the cyst’s type. Certain types of cysts are linked to underlying conditions that severely impede fertility by disrupting ovulation or causing localized damage.
When Cysts Do Not Impact Conception
The vast majority of ovarian cysts are classified as “functional cysts.” They arise naturally from the regular hormonal fluctuations of the menstrual cycle and are not pathological growths. These cysts are usually temporary and do not typically interfere with conception. The two main types are follicular cysts and corpus luteum cysts, both of which are common and generally self-resolving.
A follicular cyst forms when the dominant follicle fails to rupture and release the egg during ovulation, continuing to grow instead. Corpus luteum cysts develop after the egg is released, when the ruptured follicle seals up and fluid accumulates inside the structure that produces progesterone. Since both types are part of a functioning menstrual cycle, they usually disappear on their own within a few months without medical intervention. Their presence is generally not a cause of infertility and is often discovered incidentally.
Cysts That Directly Interfere with Fertility
Pathological cysts can directly cause fertility issues independently of systemic hormonal disorders. Endometriomas, often called “chocolate cysts” due to their dark, old blood content, are a clear example. These cysts are a manifestation of endometriosis, where tissue similar to the uterine lining grows inside the ovary. The presence of an endometrioma is strongly associated with underlying pelvic inflammation, which can negatively affect the quality of eggs and the overall ovarian reserve.
The cyst and associated inflammation can create scar tissue, known as adhesions, which physically bind the ovary to other pelvic structures. Adhesions can obstruct the fallopian tube, making it difficult for the egg to be captured and fertilized. Other non-functional cysts, such as large dermoid cysts or cystadenomas, can cause mechanical interference. If these cysts grow excessively, they can distort the pelvic anatomy, displace the ovary, or lead to ovarian torsion. Ovarian torsion is a painful twisting of the ovary that can permanently damage healthy tissue.
The Role of Underlying Hormonal Conditions
The most frequent link between “cysts” and infertility is Polycystic Ovary Syndrome (PCOS). The structures seen on the ovaries of a person with PCOS are not true ovarian cysts, but rather numerous small, arrested follicles—immature egg sacs that have stalled in development. These small follicles accumulate because the normal process of maturation and egg release is disrupted.
The core issue in PCOS is a complex hormonal imbalance, often involving high levels of androgens and insulin resistance. This hormonal environment prevents the follicles from fully developing and ovulating, leading to anovulation or highly irregular ovulation. Since pregnancy requires the regular release of a mature egg, the failure to ovulate causes fertility challenges in PCOS, not the physical presence of the follicles. PCOS is a systemic endocrine disorder, and the polycystic appearance of the ovaries is simply one diagnostic feature.
Conception After Cyst Treatment
The prognosis for conception depends heavily on the type of cyst and the treatment method used. For pathological cysts, surgical removal, known as cystectomy, is often performed to alleviate symptoms or prevent complications. Modern techniques, like laparoscopy, aim to remove the damaging cyst tissue while preserving healthy ovarian tissue. If the cyst was interfering with ovulation or distorting the pelvic structure, its successful removal may improve the chances of natural conception.
Following cystectomy, professionals recommend waiting one to three menstrual cycles before attempting to conceive to allow the ovary to heal. While surgery may temporarily reduce markers of ovarian reserve, many women with good baseline ovarian function achieve pregnancy within six to twelve months. For fertility issues associated with PCOS, treatment focuses on restoring regular ovulation, often through fertility medications like clomiphene or letrozole, which stimulate the release of an egg. Managing the underlying hormonal imbalance, rather than removing the follicles, is the pathway to improving fertility.