Chorionic hematoma | |
---|---|
Other names | Chorionic hemorrhage, chorionic bleed |
Ultrasound showing a subchorionic hemorrhage [1] |
Chorionic hematoma is the pooling of blood ( hematoma) between the chorion, a membrane surrounding the embryo, and the uterine wall. [2] It occurs in about 3.1% of all pregnancies, [2] it is the most common sonographic abnormality and the most common cause of first trimester bleeding. [3]
Chorionic hematomas can be caused by the separation of the chorion from the endometrium (inner membrane of the uterus). Hematomas are classified by their location between tissue layers: [4]
Most patients with a small subchorionic hematoma are asymptomatic. [5] Symptoms include vaginal bleeding, abdominal pain, premature labor and threatened miscarriage. [6]
Ultrasonography is the preferred method of diagnosis. [7] A chorionic hematoma appears on ultrasound as a hypoechoic crescent adjacent to the gestational sac. The hematoma is considered small if it is under 20% of the size of the sac and large if it is over 50%. [2]
The presence of subchorionic bleeding around the gestational sac does not have a significant association with miscarriage overall. [8] [9] However, the case of intrauterine hematoma observed before 9 weeks of gestational age has been associated with an increased risk of miscarriage. [10] In one study women who complied with instructions for bed rest for the duration of bleeding had a lower rate of miscarriage and a higher rate of term pregnancy than non-compliant women. The study had several limitations; results were severely confounded by inherent differences between compliant and non-compliant women. [11]
Chorionic hematoma | |
---|---|
Other names | Chorionic hemorrhage, chorionic bleed |
Ultrasound showing a subchorionic hemorrhage [1] |
Chorionic hematoma is the pooling of blood ( hematoma) between the chorion, a membrane surrounding the embryo, and the uterine wall. [2] It occurs in about 3.1% of all pregnancies, [2] it is the most common sonographic abnormality and the most common cause of first trimester bleeding. [3]
Chorionic hematomas can be caused by the separation of the chorion from the endometrium (inner membrane of the uterus). Hematomas are classified by their location between tissue layers: [4]
Most patients with a small subchorionic hematoma are asymptomatic. [5] Symptoms include vaginal bleeding, abdominal pain, premature labor and threatened miscarriage. [6]
Ultrasonography is the preferred method of diagnosis. [7] A chorionic hematoma appears on ultrasound as a hypoechoic crescent adjacent to the gestational sac. The hematoma is considered small if it is under 20% of the size of the sac and large if it is over 50%. [2]
The presence of subchorionic bleeding around the gestational sac does not have a significant association with miscarriage overall. [8] [9] However, the case of intrauterine hematoma observed before 9 weeks of gestational age has been associated with an increased risk of miscarriage. [10] In one study women who complied with instructions for bed rest for the duration of bleeding had a lower rate of miscarriage and a higher rate of term pregnancy than non-compliant women. The study had several limitations; results were severely confounded by inherent differences between compliant and non-compliant women. [11]