Drainage of subchorionic hematoma may mimic membrane rupture in early pregnancy

Headnote

Keywords: Amniotic fluid, membrane rupture, subchorionic hematoma

[PP-118]

Objective: Sudden gush of clear fluid from the vagina is a typical complaint of a pregnant patient with membrane rupture although it may also be due to leakage of urine or increased vaginal discharge. Here, we represent 2 cases with sudden fluid efflux from the vagina which is caused by drainage of a subchorionic hematoma (SCH).

Case 1: A 28-year old woman was being followed up at our antenatal clinics at her 5th pregnancy. She declined antenatal screening tests for aneuploidy. Course of the pregnancy was uneventhful until 14th gestational week at which she presented with a complaint of vaginal spotting and pelvic pain. Ultrasonographic examination revealed a healthy fetus with a big crescentric shaped SCH covering whole anterior surface of the chorion (Figure 1). At vaginal examination, cervix was closed but there was some clear to pink vaginal discharge. Uterus was tense on palpation. We decided to hospitalize her for follow up. After an hour she had a sudden gush of clear to pink fluid that wetted her bed and her clothes up to her knees. Occurrence of this sudden discharge in high quantity, appearance and odor of the fluid were similar to amniotic fluid. Then uterus got softer, ultrasound examination showed that the SCH had disappeared and amniotic fluid volume was normal. The Amnisure test(placental alpha-microglobulin-1) was also found to be positive. During the following days SCH reappeared and discharged several times. So, the fluid gush was thought to be drainage of a SCH and amnisure test result was thought to be false positive. After a week her vaginal pads became completely dry but SCH persisted up to 26th week which got progressively smaller and disappeared thereafter. Rest of the pregnancy was uneventhful and she delivered a healthy male infant of 4060 grams at 384/7 weeks of pregnancy.

Case 2: A 21-year old primigravid woman admitted at her 202/5 weeks of pregnancy a few hours after a sudden gush of fluid from the vagina thinking that she had membrane rupture. She also had mild pelvic pain. She mentioned that she had similar fluid discharge for the last 2-3 weeks, but this time it was heavier. Her antenatal follow up was uneventful except a SCH detected at ultrasound a few weeks ago. Speculum examination showed no fluid pooling in the vagina. Amnisure test was negative. Ultrasound examination revealed a healthy fetus and a normal amount of amniotic fluid. But there was an area of SCH located above the internal cervical os (Figure 2). The fluid discharge that the patient had was thought to be due to emptying of the SCH. The patient was advised to have pelvic rest and had normal amount of amniotic fluid and no complaints except minimal spotting after 4 weeks.

Conclusion: Sudden gush of fluid from the vagina during early pregnancy may be due to emptying of a SCH collection. This fluid may have a yellow to pinkish color as well as red color. Amnisure test maybe false positive. SCH drainage may clinically mimic amniotic membrane rupture.