Chronic Endometritis: Diagnosis and Treatment
What is chronic endometritis?
Chronic endometritis is a long-term, often mild, inflammatory condition of the endometrium, the inner lining of the uterus. Plasma cells in the endometrial tissue are important in diagnostic evaluation. However, there is no single standard adopted by all centers regarding which number is considered clinically significant, the timing of sampling, and the method used. Therefore, a positive result for a marker in the report alone does not automatically lead to the same treatment decision for everyone.
Chronic endometritis sometimes presents without symptoms and is only discovered during investigations for infertility or pregnancy loss. Some individuals may experience intermenstrual bleeding, irregular bleeding, or mild pelvic discomfort. These symptoms are not specific to the disease. Diagnosis is made by evaluating symptoms, intrauterine findings, and pathology together. It is incorrect to describe all pregnancy problems with the term "silent infection" or to recommend the same test kit to every woman. The reason for requesting the examination must be clearly stated.
Are chronic endometritis and endometriosis the same thing?
Although their names are similar, the two conditions are different. Endometritis is related to an inflammatory process in the inner lining of the uterus. Endometriosis, on the other hand, is a disease associated with the presence of tissue similar to the uterine lining outside the uterus. Diagnostic methods and treatment approaches are not the same. It should not be assumed that medication or intervention for one will automatically treat the other. A correct understanding of the terminology in the reports reduces unnecessary anxiety and misdirection.
The presence of an endometrioma in the ovary does not automatically mean a diagnosis of chronic endometritis. Endometrioma treatment requires a separate evaluation. Both conditions can coexist in the same person, but this needs to be demonstrated. It is important for the patient to share their previous reports and clarify which diagnosis they have received. Everyday terms like "uterine inflammation" or "chocolate cyst" do not replace a detailed medical diagnosis; the evaluation is based on the findings.
The difference between acute endometritis and chronic endometritis
Acute endometritis may present with a more pronounced infection picture, such as fever, pain, and foul-smelling discharge after childbirth or an intrauterine procedure. Chronic endometritis, on the other hand, may have a more asymptomatic course and may be detected during various investigations. This distinction is important so that someone experiencing symptoms of acute infection does not simply wait for a scheduled infertility check-up. Severe or new symptoms should be evaluated separately.
The presence of a chronic diagnosis does not mean that subsequent fever or increased pain is an expected part of the diagnosis. Healthcare should be sought if there is a significant worsening of symptoms after childbirth, miscarriage, or other procedures. Pelvic inflammatory disease is another clinical framework that can affect different parts of the upper genital system. These diagnoses may be related, but they are not always used interchangeably or require the same follow-up plan.
What are the symptoms of chronic endometritis?
Spotting, irregular bleeding, mild lower abdominal discomfort, or changes in discharge may occur in some individuals. However, the disease may be asymptomatic. The absence of symptoms does not completely rule out the diagnosis; similarly, the presence of symptoms does not prove the diagnosis. Polyps, hormonal conditions, and other intrauterine problems should be investigated, especially in cases of bleeding changes. The evaluation should not prematurely rely on a single possibility.
At the appointment, the relationship between the bleeding and menstruation, how long it has been ongoing, and whether there is pain or discharge should be explained. Medications being used, contraceptive methods, and previous procedures are also important. Keeping a diary can make details that are difficult to remember visible. Self-prescribing antibiotics based on symptom lists found online is not appropriate. Since similar complaints can stem from different causes, a targeted plan is created after examination and necessary investigations.
What causes chronic endometritis?
Chronic endometritis may be associated with certain microorganisms and an inflammatory response within the uterus. However, a single causative agent cannot be identified in every case. Accompanying intrauterine conditions such as polyps or remnants of pregnancy tissue can also affect the evaluation. A history of infection and previous procedures is inquired about, but having undergone procedures alone does not constitute a diagnosis. Evidence explaining all of the patient's findings is necessary.
Diagnosis does not constitute proof of a sexually transmitted infection or partner infidelity. If a specific infectious agent is identified, a specific approach is applied; this is not the same for all cases of chronic endometritis. Less common causes are investigated based on history and risks. It is not mandatory to perform very broad microbiological panels on every patient. What question the test will answer and how the result will change treatment should be discussed beforehand.
How is chronic endometritis diagnosed?
One of the most studied methods is the evaluation of plasma cells in a tissue sample taken from the uterine lining. Standard staining and, if necessary, immunohistochemical examination can be used. Hysteroscopy helps to assess the appearance of the uterine cavity, but the image alone does not provide a definitive diagnosis in every case. The adequacy of the sampling, the pathology method, and the clinical history are considered together.
| Method | Contribution and limitations |
|---|---|
| Endometrial biopsy | Plasma cells and other changes are investigated in the tissue; sampling characteristics are important. |
| CD138 painting | It can help in the recognition of plasma cells; however, it does not determine clinical significance on its own. |
| Hysteroscopy | It shows the intrauterine appearance and accompanying structural findings; it does not automatically replace pathology. |
| Culture or molecular examination | In selected cases, it contributes to the investigation of the causative agent; not every positive result means disease. |
| Clinical evaluation | The doctor interprets the symptoms, pregnancy history, and test results together. |
When an endometrial biopsy is recommended, the purpose of the procedure should be explained. The same sample may be examined for different clinical questions; the information in the pathology order is therefore valuable. The physician relates previous pregnancy losses or failed treatments to the pathology evaluation. A more reliable approach is to make a decision based on the entire sample and clinical context, rather than just a single line of the report.
What does CD138 positivity mean?
CD138 is a staining marker that helps detect plasma cells. However, since staining can also be seen in endometrial epithelial cells, it is important to know which cells are being evaluated. For example, the preparation, staining technique, and counting method can affect the result. International expert opinions emphasize the importance of laboratory standardization and careful interpretation. The word "positive" alone does not indicate the severity of the disease or the success of the treatment.
Different counting methods may be used in reports: the number of cells in a specific magnification area or the number of cells in the entire section is not the same measurement. Therefore, directly comparing the results from different centers can be misleading. A definitive diagnosis should not be stated based on a single number as if there were a universal threshold. It is helpful for the patient to ask, "What does this finding mean in my history?" If necessary, the details of the pathology evaluation are reviewed with the relevant specialist.
Does hysteroscopy definitively show chronic endometritis?
Hysteroscopy may reveal changes in the uterine lining, such as small polypoid structures or changes suggestive of inflammation. However, similar appearances can occur in other conditions, and interpreting the findings requires experience. A seemingly normal uterine cavity does not rule out all microscopic changes. Similarly, a suspicious appearance alone does not always constitute a definitive diagnosis requiring antibiotics.
Hysteroscopy can also allow for the evaluation of accompanying conditions such as polyps or adhesions. Before the procedure, it should be discussed whether imaging alone, a biopsy, or treatment (if deemed necessary) is planned. The possibility of pregnancy, signs of infection, and medications being used should be reported. After the procedure, it should be clarified when the pathology results will be available and who will announce them. This prevents the imaging report and tissue results from being interpreted interchangeably.
Can a vaginal culture show uterine inflammation?
A vaginal culture and an intrauterine lining culture are not the same process. Because the sample is taken from different areas, the results do not answer the same question. The presence of a microorganism in a vaginal culture does not directly prove that it causes disease in the uterine lining. In intrauterine samples, interpretive issues such as contamination and colonization during sampling must also be considered. The final result is considered in conjunction with clinical findings.
Vaginal culture tests are useful within their indications. However, a normal vaginal culture does not rule out all endometrial problems. Culture, molecular testing, and microbiome analysis are different methods. Reporting numerous microorganism names does not mean that all of them should be treated. The clinical usefulness of tests, especially those offered in commercial packages, and how they might influence treatment decisions should be questioned.
Is chronic endometritis related to infertility?
Some studies have reported a link between chronic endometritis and infertility or certain adverse reproductive outcomes. However, the patient groups and diagnostic criteria in these studies differ. Co-occurrence alone is not sufficient to establish a direct cause-and-effect relationship in every patient. Many factors related to the egg, sperm, fallopian tubes, embryo, and uterus can play a role in the failure to conceive. Reducing the entire evaluation to a single biopsy finding is not appropriate.
In infertility investigations, basic examinations and individual risks should be considered together. The diagnosis of chronic endometritis does not negate the need to investigate other causes. The patient should not be told that pregnancy is guaranteed after treatment. Improvement in diagnostic findings, clinical pregnancy, and live birth are separate outcomes. This distinction is important for correctly interpreting investigation results and treatment expectations.
Are tests necessary in cases of recurrent IVF failure?
It cannot be said that automated chronic endometritis screening should be performed after every failed embryo transfer. ESHRE's recommendations for recurrent implantation failure state that screening may be considered in appropriate patients; it does not define it as a mandatory test for all patients. Embryo characteristics, age, and individual pregnancy probability are as important as the number of transfers performed. The evaluation should not be based on a single fixed number.
When additional testing is recommended after IVF treatment , the question arises as to how the results will affect future plans. The uncertainty of the test, its cost, the need for intervention, and its potential benefits are discussed together. More testing doesn't always mean better results. However, targeted testing may be beneficial for individuals with specific histories and findings. The decision should be made through individual assessment and with a clear explanation of the limitations of the evidence.
Chronic endometritis and recurrent miscarriages
Studies on chronic endometritis have been conducted in research on recurrent pregnancy loss. However, the complete absence of pregnancy and the occurrence and subsequent loss are not the same clinical situation. Results from one patient group cannot be directly applied to another. The ASRM's 2026 opinion also addresses differences in diagnostic methods and limitations in treatment evidence. Therefore, it should not be assumed that endometritis is the sole explanation for miscarriages.
In the placebo-controlled study CERM, pre-pregnancy doxycycline did not increase live births or reduce miscarriages in women with recurrent miscarriages and chronic endometritis defined by CD138. This result cannot be generalized to all endometritis conditions, but it does not support the definitive statement that "antibiotics prevent miscarriages." The study's patient group and the outcomes it measured must be considered. The possibility of changing evidence necessitates sharing current research and uncertainties during treatment discussions.
How is chronic endometritis treated?
When the diagnosis is clinically significant, antibiotic treatment may be considered in appropriate patients. The choice is made based on the patient's history, any causative agents, allergies, the possibility of pregnancy, and other medications. There is no single antibiotic or duration that will be applied to everyone. Management of accompanying conditions such as polyps or pregnancy tissue remnants may also be necessary. The goal and success criteria of the treatment should be explained at the outset.
Taking antibiotics does not guarantee that all signs in the uterus will resolve or that pregnancy will definitely occur. Unnecessary and repeated use can lead to side effects and resistance problems. Patients should not change their medication on their own; they should discuss any decisions to stop or extend treatment with the team. It is important to report any side effects. For those planning a pregnancy, the need for contraception during treatment and when to resume trying will also be discussed.
Will a repeat biopsy be necessary after treatment?
In some clinical situations, a repeat biopsy may be considered to evaluate the response to treatment. However, it is not mandatory to collect the same number of control samples on the same date for everyone. Important questions include whether the results of the examination will affect subsequent decisions, how reliable the initial diagnosis was, and what the patient's clinical goal is. The repeat sampling plan is determined in consultation with the treating physician. It is not appropriate for the patient to follow a control schedule found only online.
Sampling and pathology methods are considered when comparing the control result with the initial result. The change in cell count should be interpreted in a clinical context. Repeated testing can sometimes increase uncertainty instead of reducing it. On the other hand, skipping necessary check-ups is also inappropriate. The decision is made by evaluating both the benefit and burden of the test. After treatment, not only the laboratory result but also changes in symptoms such as bleeding or pain are discussed.
Is chronic endometritis contagious, and does the partner need treatment?
A diagnosis of chronic endometritis alone does not necessarily require treatment of the partner. If a specific sexually transmitted infection (STI) is identified, the guidelines for managing that infection in the partner should be applied. Giving the same antibiotic to all partners without identifying the causative agent is not a general approach. This distinction is important to prevent unnecessary medication use and misunderstandings in the relationship. The meaning of the test results should be clearly explained.
Vaginal douching, herbal mixtures, or the uncontrolled application of products into the uterus are not treatments and may cause irritation or other problems. Probiotic or microbiome-regulating products have not been shown to replace diagnosis and treatment in everyone. Products used should be reported to the doctor. The word "natural" does not guarantee safety or pregnancy success. Treatment plans should be based on proven and clearly defined practices.
Pregnancy planning and check-up consultation
The timing of when to attempt pregnancy or schedule embryo transfer after treatment is determined on an individual basis. The medications used, the need for follow-up, and any accompanying intrauterine conditions influence this decision. The same number of waiting periods cannot be recommended for everyone. At the end of the appointment, the date of the follow-up, the examinations to be performed, and the discussion of the results should be clarified. This clarity strikes a balance between unnecessary delays and proceeding before the evaluation is complete.
The patient can bring the previous biopsy report, any staining results, hysteroscopy images or report, and a list of treatments used to the consultation. They should also share information about previous pregnancies or transfers, including dates. Any unclear words in the report can be noted and questioned. The patient's goal should not be simply to obtain a "negative report," but to understand the significance of the findings for their own health and pregnancy plans. The process becomes more manageable when the reasoning behind the decisions is clear.
Which symptoms require prompt medical assessment?
High fever, progressively worsening lower abdominal pain, foul-smelling discharge, heavy bleeding, or fainting should not warrant a scheduled follow-up appointment. Evaluation is particularly important if there is a new deterioration following childbirth, miscarriage, or intrauterine procedures. It is not appropriate to consider these symptoms as the natural course of a chronic diagnosis. Urgent symptoms and long-term infertility investigation should be considered separately.
For a personal consultation with Assoc. Prof. Dr. Nazlı Korkmaz, please use the contact page . The content is prepared based on ESHRE, ASRM, international expert consensus, and current research. For evidence on treatment, the results of the Warwick University CERM study can be reviewed. General information does not substitute for personal diagnosis or antibiotic prescription; the limitations of the evidence and the individual's history should be considered together.
What should be considered when reading research results?
In a study, a decrease in pathological findings and an increase in live birth rate are not the same outcome. Whether the study included a placebo or no-treatment comparison, how the patients were selected, and the criteria used for diagnosis are important. Small observational studies can raise useful questions, but they do not provide a definitive treatment rule for all patients. Reading results solely through the percentage of success can obscure these distinctions.
If the proposed approach for the patient is based on new research, the patient may be asked how similar the study is to their own case. Groups with recurrent miscarriage, recurrent transfer failure, and general infertility are not identical. Improvement in a control biopsy does not rule out other pregnancy-related factors. Therefore, the goal of the treatment, the level of uncertainty, and the alternatives should be openly discussed with the physician.
Frequently Asked Questions
Can chronic endometritis occur without symptoms?
Yes. It comes up in some people when evaluating infertility or pregnancy loss. Absence of symptoms alone is not a diagnostic or exclusion criterion.
Does a positive CD138 result definitively mean you have the disease?
It is not sufficient on its own. The cell type, counting method, sampling, and clinical history are interpreted together.
Can a smear test show chronic endometritis?
A Pap smear is a different test that evaluates cervical cells; it is not a replacement for an endometrial biopsy.
If the vaginal culture is normal, can chronic endometritis be ruled out?
No. The sample area and the question answered in the test are different.
Is pregnancy guaranteed after antibiotic treatment?
No. Pregnancy depends on many factors; it has not been definitively shown in every patient group that treatment increases the chance of live birth.
Is a biopsy needed after every unsuccessful embryo transfer?
No. The review is considered based on the clinical history and whether the outcome would necessitate a change in treatment.
Does your partner also need to take medication?
Diagnosis alone does not necessitate this. If a specific infectious agent is identified, partner management specific to that agent is applied.
Will another sample be taken after treatment?
It may be considered in some cases. Necessity and timing are determined by individual planning; there is no single control scheme for everyone.