Chocolate Cyst

Chocolate cysts also are known as Endometriomas. It can affect 5-10% of all reproductive age group women, but all of them might not have fertility problems. A woman with a chocolate cyst may be asymptomatic, or some women may experience symptoms that are almost similar to the symptoms of endometriosis. It is present in approximately 20-40% of women who have endometriosis. This pathology derives its name after the endometrium, i.e. the mucosa that lines the inside of the uterus.

What is Chocolate Cyst or Endometrioma?

Chocolate cyst of ovary or Endometrioma are non-malignant cysts growing on the ovary which are either filled with fluid or at times filled with semi-solid materials. So, in this case, it can be referred to as a complex cyst also. It is called a Chocolate cyst because the cavity of the cyst is filled with dark, old menstrual blood and tissues.

A Chocolate cyst usually forms when the endometrial tissue gets attached to the ovaries and start growing there. These endometrial cells may form small cysts first, but when stimulated with menstrual hormones, it eventually multiplies into more cysts. In response to hormones, and in the absence of pregnancy, the endometrial lining sheds and flows out in the form of menses. However, with endometriosis, the blood cannot flow out. Instead, it starts accumulating, thus irritating the adjacent tissues. Also, this can cause fibrous scars and even form cysts that are filled with blood and remnant tissues.

Symptoms of Chocolate Cyst or Endometrioma

Chocolate cysts or Endometriomas are often discovered in women between the age of 25 and 40 years, due to intense pain in the lower abdomen or if a woman faces infertility problem. However, in some cases, it may remain asymptomatic. So is only discovered during a routine gynaecological examination either through a vaginal ultrasound or X-ray. In 30%-40% of cases, women with chocolate cysts or Endometriomas can have problems getting pregnant. However, the symptoms of chocolate cysts may vary from one woman to another. The most common symptoms of Chocolate cyst are:

  • Abdominal cramps,
  • Painful periods,
  • Irregular periods,
  • Abnormal spotting or bleeding in between periods,
  • Pain in the pelvis while urinating or defecating,
  • Pain in the pelvis while exercising,
  • Painful sexual intercourse,
  • Dark coloured vaginal discharge,

Chocolate Cyst rupture symptoms: If a chocolate cyst ruptures it can cause severe pain, and its contents can enter the pelvic cavity. This discharge from the chocolate cyst can cause the ovaries to adhere to the fallopian tubes, thus creating fertility blockages and pain. So, if you have severe and sudden pain in the pelvis, you should seek immediate medical attention. A ruptured ovarian cyst is a medical emergency that needs immediate attention.

Causes of Chocolate Cyst or Endometrioma

The chocolate cyst causes or Endometrioma is still a debatable topic. According to researchers, there are several theories behind the cause of a Chocolate cyst. One of the reasons it forms is said to be due to retrograde menstruation.

During menses, the endometrial tissue breaks and needs to be excreted out of the body. However, in women with Chocolate cysts, the menstrual blood with Endometrial tissues would flow back from the Fallopian tubes to the ovaries, this would make the remnant tissues and blood to adhere to one or both the ovaries. It then slowly invades the organ and implants within the ovaries, causing cysts.

Another theory is based on disorders of the immune system, which add on to the development of endometriosis. Chocolate cysts form when the immune system cannot detect Endometriosis and starts destroying the endometrial tissue outside the uterus.

Another hypothesis suggests that abdominal cells that are present since a woman’s embryonic state retain their ability to become endometrial cells under the influence of genetic or environmental factors. Research has shown that chocolate cysts or Endometriosis run in the family, the daughters and sisters of women having chocolate cysts or Endometriosis are slightly more prone to the condition.

Diagnosis of Chocolate Cysts or Endometrioma

  • A Chocolate cyst may be discovered during a routine gynaecological examination either through a vaginal ultrasound or X-ray.
  • A Doctor might suggest a pelvic ultrasound if he or she feels a cyst during a routine pelvic examination.
  • If you are symptomatic for endometriosis
  • If you face Infertility issues
  • A Chocolate cyst can be detected on ultrasound (chocolate cyst usg), but the type of cyst cannot be identified.
  • A needle biopsy may be suggested wherein the liquid is extracted from the cyst and viewed under a microscope, to ascertain the diagnosis of a chocolate cyst.

Treatment for Chocolate Cysts or Endometrioma

It is necessary to consult a doctor and get a chocolate cyst treatment when a diagnosis has confirmed a Chocolate cyst. Because if not treated timely, it can cause infertility. The treatment plan is based on a woman’s age, symptoms, whether both ovaries are affected or not, and your reproductive status (if you want to have any children).

  • Once the diagnosis is confirmed, the doctor will prescribe a treatment based on the patient's condition. A medication-based treatment with the help of analgesics and anti-inflammatories can be prescribed to relieve pelvic pain. However, these medications sometimes do not completely treat the problem and should be coupled with a hormonal treatment, which works by blocking the production of hormones by the ovaries, which reduces bleeding.
  • Chocolate cysts or Endometriomas which are large in size (more than 4 cm), are painful, which may be a reason of infertility and may turn cancerous (though very rare), then an ovarian cystectomy is suggested to remove the cyst. Through laparoscopy, the endometrial excrescences, scar tissue and adhesions that are often the origin of infertility are removed, thus preserving the uterus and ovaries. During laparoscopy, there are increased chances that healthy ovarian tissue can be removed along with the cyst. This, in a way, can have a negative impact on the ovarian reserve and ovarian function.
  • In severe cases of endometriosis, if the symptoms keep coming back, and a cystectomy or adhesiolysis (removal of adhesions) were not able to cure the diseases then a hysterectomy (part or complete removal of the uterus) might be recommended as a last resort, keeping in mind the woman’s reproductive status and age. So, if a woman is above the age of 35 years and her family is complete, then complete removal of the ovaries and uterus is recommended.
  • If chocolate cyst size is small, asymptomatic and benign, then follow up with imaging tests is suggested.
  • In women during the postmenopausal period, the detection of cyst on ultrasonography and the value of CA 125 help define the best course of action. If the cyst is benign and the CA 125 is low, the doctor will only suggest scanning every 3 or 6 months. If there is still a doubt about the innocuousness of the injury, surgery may be the most recommended option.

Chocolate Cysts Effect on Fertility

Chocolate cyst and pregnancy - Chances of pregnancy are there if there is only one chocolate cyst and that too small in size. If it remains small (just a few millimeters in size), then it is not a cause for concern. However, some cysts grow large (over 10 cm) and become very painful with the menstrual cycle.

  • A woman with a Chocolate cyst may have fewer eggs left in her ovary, the eggs may not mature, and she may have high levels of Follicle Stimulating Hormones (FSH) which might suggest problems in her ovaries.
  • Larger cysts tend to be the most problematic for fertility. If an Endometrioma ruptures, its contents can enter the pelvic cavity. This can cause the ovaries to adhere to the fallopian tubes creating fertility blockages and pain.
  • A Chocolate cyst can cause scarring in the fallopian tube, and this may affect the movement of the sperm and egg. If also fertilisation takes place the risk of ectopic or tubal pregnancy stays.
  • A Chocolate cyst might interfere with the implantation of a fertilised egg, due to an imbalance in reproductive hormones, so the risk of miscarriage increases.
  • Chocolate cysts disturb the normal tubo-ovarian relationship. In severe cases, Endometriomas can affect ovarian reserve, damage the ovaries, or even require oophorectomy (removal of the infected ovary, and keeping the other ovary intact) which can make a female infertile.

Chocolate cyst & In vitro Fertilisation

Before undergoing any treatment, and if you are facing difficulty in conceiving due to a chocolate cyst, it is advisable to visit an Infertility specialist. Looking at your medical history and the graveness of your cyst, she may suggest the best treatment plan for you.

  • IVF is an option if a woman is facing difficulty in conceiving, though it may possess some risks. However, here, the experience of a Doctor counts in while doing any surgical intervention. The risks associated are:
  • Women with Endometriomas or chocolate cyst respond slowly to gonadotropins, which might increase the rate of IVF cancellation cycles.
  • The location of the cyst plays a significant role as it might interfere with egg retrieval.
  • The risk of the Chocolate cyst being punctured during an egg retrieval process stays, which causes the cyst to rupture thus leading to infection.
  • The fluid present inside the chocolate cyst might contaminate the follicular fluid, thus decreasing the chances of blastocyst hatching and thereby lowering pregnancy rate.
  • Fertility Preservation should be considered for women who plan to undergo surgery for endometriomas, because surgery may decline AMH (Anti Mullerian Hormones) levels significantly, cause inflammation, healthy ovarian tissue can be removed. So, a woman has the risk of going into Premature Ovarian Failure, which might cause early menopause.


Women who have Endometriosis may have a high risk of developing a chocolate cyst or endometrioma. If they are small, they can be managed well medically; in some cases, they might need to be removed. According to research in 30% of cases if the chocolate cyst was large, then it can recur. It can affect fertility, so if you are planning a pregnancy, best is to visit a doctor and get your treatment plan accordingly. For more information, you can visit us at Medicover Fertility or call us at +917862800700.

Frequently Asked Questions

Can Chocolate cyst be cancerous?
Does Chocolate cyst go away on their own?
Can Chocolate Cyst affect pregnancy?
What causes Endometriomas or Chocolate Cyst?