2022 Volume 10 Issue 3 Pages 97-100
Puerperal hematoma is a serious obstetric complication. We report a case of a large puerperal hematoma with an uncommon feeding vessel originating from an inferior mesenteric artery. A 28-year-old primiparous woman was transferred to our hospital with a large hematoma in the left vaginal wall following normal vaginal delivery. Contrast-enhanced CT revealed an actively bleeding vulvovaginal hematoma 9 cm in diameter, and transcatheter arterial embolization was performed. Arteriogram of the internal iliac arteries did not reveal a feeding vessel. Embolization of the peripheral branch of the superior rectal artery, which originated from the inferior mesenteric artery, achieved hemostasis. If the internal iliac arteries are not the source of active bleeding, more proximal angiography of the inferior mesenteric artery is recommended to assess uncommon feeding vessels.
Puerperal hematoma is one of the most serious obstetric complications with an incidence of 1–3 per 1,500 vaginal deliveries and carries a risk of hemorrhagic shock.1) Risk factors of puerperal hematoma include nulliparity, birth weight >4,000 g, prolonged second-stage labor, hereditary clotting deficiencies, episiotomy, and operative vaginal delivery.1) Transcatheter arterial embolization (TAE) is used to treat vulvovaginal hematomas, allowing early hemostasis and avoiding blood transfusion.2,3,4) In most cases, peripheral arteries of the internal iliac arteries (IIAs), which commonly include the uterine, perineal, and vaginal arteries, are involved in the formation of a puerperal hematoma.4,5) Here we report a case of puerperal hematoma with an uncommon feeding artery originating from an inferior mesenteric artery (IMA).
A 28-year-old woman (gravida 1, para 0) was transferred to our hospital with a puerperal hematoma. She had delivered a 3,300 g newborn via normal vaginal delivery at 38 weeks and 4 days of gestation. During labor, a right episiotomy was performed; estimated blood loss was 130 g by the end of the third stage of labor. Postpartum examination of the genital tract revealed a laceration in the left vaginal wall. During suturing, a hematoma gradually grew in the left vaginal wall. An effort was made to remove the clotted blood, and the wound was immediately re-sutured. Although the additional blood loss was 35 g over 1 h, she complained of severe vulvar pain 3 h after delivery. The hematoma had grown over the left vaginal wall and vulva, and she was urgently transferred to our hospital.
On admission, she complained of intractable vulval pain. Her blood pressure was 115/85 mmHg, heart rate was 90 beats/min, and Hb level was 12.0 g/dl. Emergency contrast-enhanced CT revealed a large vulvovaginal hematoma (70×79×97 mm) on the left anterior side of the vulva, with active bleeding (Figure 1-A). The vulvovaginal hematoma appeared to have developed from the peripheral branch of the IMA (Figure 1-B and C). The IMA descended in front of the sacrum and branched into the superior rectal artery, coursing toward the right side through the dorsal side of the rectum. This peripheral branch of the superior rectal artery appeared to have caused extravasation in the vulvovaginal area.
Contrast-enhanced CT scans before angiography.
(A) Coronal image. The arrow indicates a large vulvovaginal hematoma (70 x 79 x 97 mm).
(B and C) Sagittal images. Arrows indicate the vessel traveling from the inferior mesenteric artery (IMA) to the vulvovaginal hematoma.
TAE was performed as the first-line treatment. As anticipated from prior CT images, angiography revealed extravasation originating from one of the branching vessels of the IMA. Embolization with gelatin sponges was performed up to the right peripheral branch of the superior rectal artery (which emerged from the IMA), because this branch appeared to be feeding the vaginal wall (Figure 2). Embolization of the IMA branch led to hemostasis. Angiography of the IIA and internal pudendal arteries revealed no active bleeding. After TAE, the Hb level was 9.0 g/dl, the puerperal hematoma stopped growing, and vulval pain disappeared. Two days later, we opened the hematoma and removed more than 100 g of clotted blood. Blood loss during the operation was approximately 100 g; a drain was inserted to accelerate healing. Postoperative blood Hb level was 8.3 g/dl. The patient was discharged at 7 days postpartum without any complications.
Angiography of the inferior mesenteric artery (IMA).
(A) A branch of the superior rectal artery. (B) Active bleeding from the right peripheral artery of the superior rectal artery.
In the present case, a puerperal hematoma was caused by damage to an uncommon feeding vessel originating from the IMA. Several management options are available for vulvovaginal hematomas in the puerperium, including conservative approaches, surgery, and TAE. Conservative approaches are often preferred for hematomas <5 cm in diameter and involve the use of ice packs, pressure dressings, analgesia, and/or antibiotics.6) Surgical procedures are required when hematomas are expanding (≥5 cm in diameter) or associated with an estimated blood loss >200 g.6) TAE is minimally invasive and can ensure hemostasis if surgical ligation of the active bleeding site is difficult. If initial CT reveals an actively bleeding vessel, TAE is recommended prior to surgery to establish hemostasis and avoid mortality from massive bleeding.2,3) In particular, TAE should be initially considered if rebleeding occurs after surgical ligation, as identifying the bleeding site can be difficult and the extent of bleeding may further increase.2) After achieving hemostasis by TAE, surgical removal of the hematoma can be beneficial to reduce the risk of bacterial infection, especially in cases where surgical hemostasis has already been attempted and failed. Moreover, since it takes time for a large hematoma to be absorbed, surgical hematoma removal is preferable than waiting for spontaneous absorption from the perspective of enabling smooth postpartum recovery to begin newborn care.
Puerperal hematomas develop due to damage to feeding vessels commonly originating from the IIAs, which feed the female genital tract both anteriorly and posteriorly.5) The anterior IIA branches include the umbilical, superior vesical, obturator, inferior vesical, vaginal, middle rectal, internal pudendal, inferior gluteal, and uterine arteries; the posterior branches include the iliolumbar, lateral sacral, and superior gluteal arteries.5) Puerperal hematomas are classified as vulvar, paravaginal, and retroperitoneal.3,4) Vulvar hematomas commonly develop in the perineal artery (a branch of the internal pudendal artery). In the case of paravaginal hematomas, the internal pudendal and vaginal arteries, and the cervicovaginal branch of the uterine artery, are common feeding vessels. As for retroperitoneal hematomas, the internal pudendal and uterine arteries, as well as vessels in the broad ligament of the uterus, are likely to be involved.4,5) As mentioned above, most puerperal hematomas develop in the branches of the IIAs. However, in the present case, a peripheral vessel of the superior rectal artery (a branch of the IMA) was the feeding vessel. Selective angiography of the IIAs revealed no extravasation to the hematoma.
The IMA supplies the large intestine from the distal transverse colon to the upper part of the anal canal and has three branches (left colic, sigmoid, and superior rectal arteries). A few reports have described collateral arterial circulation between arteries in the female pelvis and the thoracic/abdominal aortae, suggesting that an IMA branch can produce collaterals that run to the uterus or genital tract.7,8) In the present case, it is possible that the superior rectal artery from the IMA might have produced collaterals in the vulvovaginal area, and damage to these vessels during vaginal delivery led to the formation of a large hematoma.
Few reports have described TAE of the IMA to manage postpartum hemorrhage. Cases of successful IMA embolization in patients exhibiting persistent bleeding after thorough embolism of the bilateral uterine arteries from the IIAs have been reported, and the possibility of substantial genital tract injury causing damage to the superior rectal artery has been discussed.9,10) Reportedly, the IMA can be an unusual extrauterine source of post-partum hemorrhage,10) although the frequency of postpartum hematoma due to damage to the IMA is unknown. In our patient, contrast-enhanced CT images before angiography revealed extravasation in the superior rectal artery branch, i.e., the peripheral artery of the IMA. Initial angiography of the IMA successfully identified the branch responsible for active bleeding and hemostasis was achieved by embolization.
TAE of postpartum hemorrhage is associated with both major and minor complications. Major complications include hemoperitoneum caused by vessel rupture and zonal ischemia including uterine necrosis, which compromises future fertility. Minor complications include postembolization syndrome (fever, mild leukocytosis, and pelvic pain), transient ischemia, puncture site hematoma, and allergic reaction to the contrast dye.5) When embolizing the IMA branches including the superior rectal artery, bowel complications such as ischemia should also be considered.9) We encountered no major or minor complications in the present case.
In conclusion, puerperal hematoma can be caused by damage to an uncommon feeding vessel originating from the IMA. If arteriography of the uterine artery, or other branches of the IIA, does not reveal the site of bleeding, more proximal screening (including the IMA) is recommended to assess uncommon feeding vessels.
TAE: Transcatheter arterial embolization
IIA: Internal iliac artery
IMA: Inferior mesenteric artery
We appreciate Dr. Keisuke Tanno and members of Department of Radiology, Jichi Medical University, Saitama Medical Center for their support based on radiodiagnosis and TAE, and Dr. Liangcheng Wang and Dr. Ken Imai for their collaboration and feedback regarding this case.
The authors report no conflicts of interest.
