Hematometra is a pathologic collection of blood in the uterus. It is a rare condition that is most commonly associated with congenital anomalies or prior surgical procedures causing obstruction of the genitourinary outflow tract.
Hematometra is a medical condition that involves the collection of blood in the uterus. The most common cases occur due to uterine, cervical, and vaginal malformations; whereas, medical cases that cause obstruction of the cervical canal are far rarer. Imperforate hymen is a rare malformation of the vagina and a possible reason of hematocolpos and hematometra in puberty. This genital tract malformation has an incidence of 0.05% to 0.1%. This sporadic condition usually presents itself with the presence of a mass, lower abdominal pain, delayed menarche, and bulging vaginal membrane.
Acquired obstruction of the lower female genital tract is rare.[rx] Hematometra is retention of blood in the uterine cavity caused by obstruction to menstrual flow at the level of the uterus, cervix, or vagina. In older women, the obstruction is usually acquired and occurs at the level of the cervix.[rx] In young women, hematometra may be due to congenital anomalies such as an imperforate hymen or a noncommunicating Müllerian duct.[rx] Transabdominal sonography is a noninvasive imaging modality useful for examining occlusions of the genital tract.[rx] Transvaginal sonography is important in the evaluation of hematometra because it affords clear visualization of the endometrial cavity.[rx]
Types of Hematometra
The genital tract becomes dilated above the obstruction. If the dilation contains blood the terms used are:
- Haematocolpos: vaginal distension – obstruction at the vaginal level
- Haematometrocolpos: vaginal and uterine distension – obstruction at the vaginal level
- Haematometra: uterine distension – obstruction at the cervical level
- Haematosalpinx: dilation of fallopian tubes – obstruction at cornua.
Causes of Hematometra
Hematometra develops when the uterus becomes distended with blood secondary to obstruction or atresia of the lower reproductive tract—the uterus, cervix or vagina—which would otherwise provide an outflow for menstrual blood.[rx] It is most commonly caused by congenital abnormalities, including imperforate hymen, transverse vaginal septum or vaginal hypoplasia. Other causes are acquired, such as cervical stenosis, intrauterine adhesions, endometrial cancer, and cervical cancer.[rx]
Additionally, hematometra may develop as a complication of uterine or cervical surgery such as endometrial ablation, where scar tissue in the endometrium can “wall off” sections of endometrial glands and stroma causing blood to accumulate in the uterine cavity. It can also develop after abortion, as well as after childbirth. It can also develop after female genital mutilation.
- The genital tract dilates above any congenital obstruction.
- An intact hymen is the commonest cause.
- An MR scan is almost 100% accurate in diagnosing congenital gynaecological anomalies.
- There is an association with renal anomalies.
- Primary amenorrhoea commonest presentation of an obstructed track.
- Ultrasound will show the dilated tract as a central fluid-filled mass.
- Failure to identify the uterus should always raise the possibility that an abnormal mass is in the uterus.
- It may be caused by Müllerian duct anomalies.
- Imperforate hymen.
- In older women, it may be secondary to carcinoma of the cervix or cervical stenosis (eg following cone biopsy).
- Other causes include infection with Listeria monocytogenes, laser endometrial ablation, uterine curettage and cervical cryocoagulation or electrocoagulation.
- It may be the result of childbirth, either by normal vaginal delivery or assisted deliveries, such as forceps.
- Acute haematometra is a rare complication following induced termination of pregnancy.
Symptoms of Hematometra
Hematometra typically presents as cyclic,
- cramping pain in the midline of the pelvis or lower abdomen.[rx] Patients may also report urinary frequency and urinary retention.[rx]
- Premenopausal women with hematometra often experience abnormal vaginal bleeding, including dysmenorrhea (pain during menstruation) or amenorrhea (lack of menstruation), while postmenopausal women are more likely to be asymptomatic.[rx]
- Due to the accumulation of blood in the uterus, patients may develop low blood pressure or a vasovagal response.[rx] When palpated, the uterus will typically feel firm and enlarged.[rx]
- Amenorrhoea, but there may be some menstrual blood flow.[rx]
- Lower abdominal swelling and tenderness.
- It may present with severe primary dysmenorrhoea.
- It may be associated with pyometra, especially after the termination of pregnancy, when the patient may have a high fever and other evidence of infection.
- If due to an imperforate hymen, and therefore associated haematocolpos develops, the hymen may bulge and exhibit a bluish discoloration.
Diagnosis of Hematometra
Although hematometra can often be diagnosed based purely on the patient’s history of amenorrhea and cyclic abdominal pain, as well as a palpable pelvic mass on examination, the diagnosis can be confirmed by ultrasound, which will show blood pooled in the uterus and an enlargement of the uterine cavity.[rx][rx] A pyelogram or laparoscopy may assist in diagnosing any congenital disorder that is suspected to be the underlying cause of the hematometra.[rx]
Treatment of Hematometra
Hematometra is usually treated by surgical cervical dilation to drain the blood from the uterus.[rx] Other treatments target the underlying cause of the hematometra; for example, a hysteroscopy may be required to resect adhesions that have developed following previous surgery.[rx] If the cause of the hematometra is unclear, a biopsy of endometrial tissue can be taken to test for the presence of a neoplasm (cancer).[rx] Antibiotics may be given as prophylaxis against the possibility of infection.[rx]