Minimally invasive management of intramural pregnancy using ultrasound combined with laparoscopy -based learning experience from a low-middle income country: a case report and review of the literature.

Intramural pregnancy is a rare form of ectopic pregnancy; however, a delayed treatment could lead to disastrous events. In a suspected case of IP, the patient should be transferred and managed at tertiary referral hospital with multidisciplinary team. In an early term of pregnancy, laparoscopy along with ultrasound for conservative treatment of the uterus could be an alternative option to hysterectomy under laparotomy for this extreme rarity. Thus, reproductive function is preserved for the women desiring the future fertility and avoiding the removal of the uterus.

Until today, the accurate etiology of IP remains unknown. Adenomyosis, history of salpingectomy, assisted reproductive technology with embryo transfer, and previous uterine cavitary intervention such as cesarean section, which left the tiny tunnels in the myometrial layer, may be risk factors in this case [ 1 , 2 , 6 ]. In the present case, the diagnosis of intramural pregnancy was missed at an initial ultrasound examination and the right adnexal ectopic pregnancy was initially presumed at the local hospital due to the history of right salpingectomy. However, the patient was diagnosed with an uncommonly located site after laparoscopic observation. Therefore, the detection of IP could be a challenge in several situations. According to the report of Nijjar et al ., only 50% cases of IP were diagnosed correctly at the initial visit. An intramural pregnancy was diagnosed on transvaginal and/or transabdominal ultrasound if it was implanted within the uterine corpus above the level of the internal cervical os and separate from the interstitial section of the fallopian tube, and without a connection with uterine cavity. IP should be subdivided into partial or complete forms, which depend on the depth of myometrial involvement and the indistinct boundary from the decidual–myometrial junction [ 3 , 7 ]. This feature should also be differentiated from cesarean scar pregnancy [ 8 , 9 ]. Three-dimensional ultrasound with Doppler signal could be added. A trophoblastic peripheral blood flow shows clearly IP mass [ 10 ]. Nevertheless, the ectopic pregnancy mass may be embedded in the myometrium, and presents as a prominent budge from the posterior uterine wall and located under the ovarian ligament. This dilemma location could be a pitfall in an imaging assessment and the initial diagnosis is commonly an ectopic pregnancy relating to fallopian tubes, cornual, and interstitial site [ 6 , 11 ]. Specifically, non-invasive modalities consisting of magnetic resonance imaging could be considered [ 12 ]. Accordingly, the accurate diagnosis may be made at an exploratory laparoscopy [ 6 ]. In intramural pregnancy, almost all cases are asymptomatic (Table  1 ). Typically, the slight symptoms such as vaginal bleeding and intermittent abdominal pain have been reported. A preoperative ruptured uterus with heavy vaginal bleeding at 3.2 L and 5 units of blood transfusion, and admitted to ICU has been mentioned in the first trimester [ 3 ]. A rupture complication leading to life-threatening hemorrhage in late pregnancy has rarely been documented due to the development of health-care system worldwide. In accordance with Chen et al ., GA > 10 weeks was the risk factor for both uterine rupture and hysterectomy, while patients with GS located in the uterine fundus had a significantly higher risk of uterine rupture [ 1 ]. Table 1 Uterine conservative management among intramural pregnancies in the literature in the past 5 years Authors, year, country Patient age Gravida, parity, risk factors GA Symptoms β-hCG level (mIU/mL) Ultrasound features Gestational size Surgical interventions and other treatments Outcomes Zhang et al ., 2019, China [ 15 ] 30 years -G1P1 -CS 4 yrs ago 6 weeks Unprovoked vaginal bleeding 22,805 -GS with echogenic yolk sac and embryo with primordial cardiac pulsation -GS measuring 10 mm × 7 mm × 8 mm located in the posterior uterine wall -Resection under laparoscopy -MTX injection at the defect myometrium - β-hCG declined to 2012 mIU/ml on the second day after surgery -Uneventful follow-up Liu et al ., 2020, China [ 6 ] 28 years -G2P1 -IVF-ET -Salpingectomy 7 weeks Asymptomatic 2174.04 -Suspected of a right adnexa EP, right interstitial fallopian or right uterus corneal pregnancy -Hypoechogenic structure without sign of gestation sac - 14 × 13 mm in size -Exploratory laparoscopy -Hysteroscopy -Excised the lesion followed by repairing the defect with careful electrocoagulation -EBL at 100 mL -β-hCG level dropped to 4.36 mIU/mL 14 days after the surgery Nees et al ., 2020, Germany [ 21 ] 24 years -One miscarriage -CS at 9 weeks due to obstructed labor -Obesity 9 weeks Asymptomatic 53,000 -A 43 mm × 35 mm mass containing a gestational sac with a viable embryo -The mass did not appear to communicate with either the fallopian tube or uterine cavity -Laparotomy for uterine wedge resection -Uneventful postoperative course -Subsequent pregnancy of more than 34 weeks Chen et al ., 2021, China (3 cases) [ 1 ] 20 years -G1P0 -Artificial abortion 17 weeks 2 days Vaginal bleeding Absent -A live fetus was noted in GS located within myometrium -Laparotomy, hysterotomy, enucleation of conceptus, and hysteroplasty -Abdominal aorta balloon occlusion -EBL at 300 mL -Uneventful postoperative course 42 years -G4P1 -Artificial abortion and induced abortion 7 weeks Asymptomatic 19,140 -GS was located in the left posterior wall of the uterine fundus, the muscular layer between the uterine cavity and GS was about 5 mm in thickness -Mifepristone and intramural MTX before admission -Laparoscopy -EBL at 150 mL -Uneventful postoperative course 38 years -G2P1 -CS 13 months ago 10 weeks Vaginal bleeding 521.9 -GS at the left posterior wall of the uterine, closed to the left corner of the uterus, without connected with the uterine cavity -Curettage combined with mifepristone before admission -Laparoscopic excision - Hysteroscopy -EBL at 200 mL -Uneventful postoperative course Xie et al ., 2022, China [ 10 ] 31 years G3P0 Salpingectomy IVF-ET 7 weeks Asymptomatic 1759 -Three-dimensional TVS indicated a heterogeneous echogenic area measuring 1.40 cm × 1.26 cm in size arising from the uterine fundus, which had a 0.48 cm × 0.37 cm anechoic region inside and was surrounded by myometrium -Uterine adenomyoma -Removal of IP mass using laparoscopy -MTX was injected into the myometrium around the wound -β-hCG levels were negative after 4 weeks Nijjar et al ., 2023, UK (18 cases) [ 3 ] Median age was 35 (28–43) -G: 3 (1–9), P: 0 (0–3) -Suction evacuation -Laparoscopic myomectomy -CS -Manual removal of placenta -Operative hysteroscopy 8 weeks + 1 day (range, 5 weeks + 5 days to 12 weeks + 0 days) -Vaginal bleeding with or without abdominal pain was the most common From 584 to 165,903 -Nine (50%) patients had a partial and nine (50%) had a complete intramural pregnancy -ECA was present in eight (44%) pregnancies -The majority of pregnancies ( n  = 10 [56%]) were initially managed conservatively, including expectant management in eight (44%) cases,local injection of MTX in one (6%) and embryocide in one (6%) -Conservative management was successful in 9 of 10 (90%) pregnancies, with a median time to β-hCG level of 71 (range, 35–143) days Kubo et al ., 2024, Japan 33 years -G2P0 -Twice D and C 6 weeks Asymptomatic 27,655 -A gestational sac measuring 26 mm, an embryo of 3 mm in length, and ECA in the anterior muscular layer of the uterus, away from the endometrium Total laparoscopic wedge resection using intraoperative US -EBL at 45 ml -Uneventful follow-up - β-hCG was negative after 60 days Le et Nguyen, 2024, Vietnam (indexed case) 34 years -G3P1 -Salpingectomy 5–6 weeks Asymptomatic 13,070 -GS measuring 16 × mm 20 mm × 20mm in size, contained a yolk sac -The mass located within the anterior wall of the uterus -Laparoscopy with US - β-hCG was negative after 1 month -Uneventful follow-up β-hCG, beta-human chorionic gonadotropin; CS, cesarean section; D and C, dilation and curettage; EBL, estimated blood loss; ECA, embryonic cardiac activity; EP, ectopic pregnancy; IP, intramural pregnancy; IVF-ET, in vitro fertility with embryo transfer; MTX, methotrexate; GP, gravida, parity; GA, gestational age; GS, gestational sac; TVS, transvaginal sonography; US, ultrasound, yo, years old Uterine conservative management among intramural pregnancies in the literature in the past 5 years -G1P1 -CS 4 yrs ago -GS with echogenic yolk sac and embryo with primordial cardiac pulsation -GS measuring 10 mm × 7 mm × 8 mm located in the posterior uterine wall -Resection under laparoscopy -MTX injection at the defect myometrium - β-hCG declined to 2012 mIU/ml on the second day after surgery -Uneventful follow-up -G2P1 -IVF-ET -Salpingectomy -Suspected of a right adnexa EP, right interstitial fallopian or right uterus corneal pregnancy -Hypoechogenic structure without sign of gestation sac - 14 × 13 mm in size -Exploratory laparoscopy -Hysteroscopy -Excised the lesion followed by repairing the defect with careful electrocoagulation -EBL at 100 mL -β-hCG level dropped to 4.36 mIU/mL 14 days after the surgery -One miscarriage -CS at 9 weeks due to obstructed labor -Obesity -A 43 mm × 35 mm mass containing a gestational sac with a viable embryo -The mass did not appear to communicate with either the fallopian tube or uterine cavity -Uneventful postoperative course -Subsequent pregnancy of more than 34 weeks -G1P0 -Artificial abortion -Laparotomy, hysterotomy, enucleation of conceptus, and hysteroplasty -Abdominal aorta balloon occlusion -EBL at 300 mL -Uneventful postoperative course -G4P1 -Artificial abortion and induced abortion -Mifepristone and intramural MTX before admission -Laparoscopy -EBL at 150 mL -Uneventful postoperative course -G2P1 -CS 13 months ago -Curettage combined with mifepristone before admission -Laparoscopic excision - Hysteroscopy -EBL at 200 mL -Uneventful postoperative course Xie et al ., 2022, China [ 10 ] G3P0 Salpingectomy IVF-ET -Three-dimensional TVS indicated a heterogeneous echogenic area measuring 1.40 cm × 1.26 cm in size arising from the uterine fundus, which had a 0.48 cm × 0.37 cm anechoic region inside and was surrounded by myometrium -Uterine adenomyoma -Removal of IP mass using laparoscopy -MTX was injected into the myometrium around the wound Nijjar et al ., 2023, UK (18 cases) [ 3 ] Median age was 35 (28–43) -G: 3 (1–9), P: 0 (0–3) -Suction evacuation -Laparoscopic myomectomy -CS -Manual removal of placenta -Operative hysteroscopy -Nine (50%) patients had a partial and nine (50%) had a complete intramural pregnancy -ECA was present in eight (44%) pregnancies -G2P0 -Twice D and C -EBL at 45 ml -Uneventful follow-up - β-hCG was negative after 60 days -G3P1 -Salpingectomy -GS measuring 16 × mm 20 mm × 20mm in size, contained a yolk sac -The mass located within the anterior wall of the uterus - β-hCG was negative after 1 month -Uneventful follow-up β-hCG, beta-human chorionic gonadotropin; CS, cesarean section; D and C, dilation and curettage; EBL, estimated blood loss; ECA, embryonic cardiac activity; EP, ectopic pregnancy; IP, intramural pregnancy; IVF-ET, in vitro fertility with embryo transfer; MTX, methotrexate; GP, gravida, parity; GA, gestational age; GS, gestational sac; TVS, transvaginal sonography; US, ultrasound, yo, years old The β-hCG level is not useful in diagnosis of intramural pregnancy. However, an ongoing intramural pregnancy (IP) should be differentiated from retained products of conception, as well as gestational trophoblastic disease, since an abundant Doppler signal is often present [ 13 , 14 ]. The histology plays an important role in identifying the features of trophoblastic villi after surgery. According to Zhang et al ., non-specific clinical presentation and non-uniform ultrasound criteria pose a challenge for us to make timely and accurate management. Integrated radiological examinations, communication, and cooperation between sonographers and gynecologists play a vital role in diagnostic accuracy and selecting the optimal therapeutic method of an intramural pregnancy [ 15 ]. Upon detection of intramural ectopic pregnancy, the treatment ought to be chosen by termination of pregnancy, whether emergency or planned surgery. However, due to lacking strong evidence, the management remains controversial. The proper management should be individualized based on the size of mass, the gestational age, the presence of symptoms, desire of the patient, and the available resources of hospital as well as the experience of surgeon [ 5 ]. Currently, the option includes expectant management (a wait-and-see approach), methotrexate administration, potassium chloride injection, hysterectomy, and conservative management by laparotomy and laparoscopy [ 2 , 3 , 16 ]. In a summary of eighteen IP cases, Nijjar et al . found an IP mass with an embryo measuring 38.1 mm in length, presenting with embryonic cardiac activity, and requiring emergency hysterectomy due to heavy vaginal bleeding after expectant management [ 3 ]. Pre- and intraoperative management includes ascertaining the possibility of heterotopic pregnancy, which ought to be excluded by ultrasound, and accompanied hysteroscopy at operating room [ 17 , 18 ]. Regarding preservative management, Kong et al . reported an extremely rare case of non-ruptured intramural pregnancy at 17 weeks of gestation, which was managed successfully by hysteroplasty instead of hysterectomy. Before surgical intervention, a balloon was placed in the abdominal aorta between the opening of renal artery and iliac artery to minimize the massive bleeding. Thus, the future fertility of the patient was preserved [ 12 ]. In some cases, uterine artery embolization (UAE) may be applied. Injecting diluted terlipressin into the myometrium around the mass may also be helpful in reducing blood loss [ 15 ]. Recently, Kubo et al . have reported the first case of a total laparoscopic wedge resection using an intraoperative ultrasound system with reliable outcome [ 19 ]. To the best of our knowledge, the present case was seemingly the unique report combining the routine ultrasound with laparoscopy for determining the pregnancy mass location and complete excision. At our center, the team also applied this technique for the resolve of interstitial heterotopic pregnancy [ 18 ]. In addition, we peripherally sutured the uterine wall containing the pregnancy mass to minimize severe hemorrhage during the resective procedure. During conservative surgery, conversion to supracervical hysterectomy should be performed if the hemostatic procedures are failed. After conservative management, the β-hCG level and repeated ultrasound should be monitored regularly within 2–4 weeks, since the risk of retained product of conception in myometrial layer. The diluted methotrexate administration could be injected into the defect in the myometrium to kill the activity of possibly residual trophoblast cells [ 15 ]. The MTX injection may be applied as a local injection and by systemic administration in an uncommon location site [ 20 ]. The contraceptive method should also be informed to the patient and her partner since the high risk of a ruptured uterus after a myometrial incision. This is similar to the patient management after myomectomy. The patient should wait at least 1 year before becoming pregnant again. Moreover, the time for termination of pregnancy after 34 weeks should be discussed with the patient after considering the benefit of mother and fetus [ 21 ]. However, the outcome following the uterine repair remains unclear. The menstrual status, dysmenorrhea, uterine synechia, and the subsequent pregnancy with uterine rupture, preterm birth, and abnormal placenta adhesion have not been documented. Further data are required to support the current conservative management.

Intramural pregnancy (IP) is characterized by the implantation of pregnancy within the myometrial structure, without connecting with the endometrium. This uncommon form occurs less than 1% of ectopic pregnancies [ 1 ]. Although this is a rare entity, IP could lead to a potentially life-threatening condition. Until 2024, 82 cases have been summarized in the literature [ 2 ]. Almost all cases were detected in the first trimester, and there was a very rare case of an ongoing IP that was reported at 20 weeks of gestation [ 3 ]. An accurate diagnosis of IP could be made by abdominal ultrasound. However, it may require more modalities such as three-dimensional transvaginal ultrasound or exploratory laparoscopy [ 3 ]. Previously, IP were mainly treated by laparotomy and underwent hysterectomy due to high risk of uterine rupture and severe bleeding. Recently, the conservative management of the uterus has been greatly concerned due to the development of interdisciplinary team assessment. In 2020, Shen et al . documented that only ten cases were successfully managed by laparoscopic intervention [ 4 ]. In 2023, Nijjar et al . reported a highly successful rate of uterine conservative management among 18 intramural pregnancies in over a period of 14 years [ 3 ]. Similar to the common management of ectopic pregnancy, an appropriate surgical intervention should be selected with facility capabilities, context, patient’s condition, and surgeon’s experience [ 5 ]. Hereby, we describe a noteworthy case of IP treated with ultrasound-guided laparoscopy and string suture technique at our tertiary referral hospital. Using these concomitant procedures, we successfully maintained the future fertility for this woman.

A 34-year-old Vietnamese woman (gravida 3, parity 1) was transferred from an outside hospital for ultrasound and laparoscopy, since the patient was diagnosed with an uncommonly located site of ectopic pregnancy following a late menstrual period of 2 weeks and elevated serum beta-human chorionic gonadotropin (β-hCG). The ectopic pregnancy was suspected to present at the isthmic location and emerged in the broad ligament. Before surgical intervention, the patient was totally asymptomatic. At hospitalization, the vital signs were noticeably normal. The woman was noted with a history of the right fallopian tube removal due to tubal ectopic pregnancy 7 years ago and a history of cesarean section at term pregnancy 5 years ago. She denied taking emergency contraception pills. No past history of diseases was recorded. Her medical record and her psychosocial history, as well as her family disease history, were unremarkable. A difficult diagnosis was made at an initial assessment. Her β-hCG level measured at 13,070 mUI/mL. However, a pregnancy of unknown location was made owing to an empty uterine cavity. Later, a repeated ultrasound showed an adenomyosis uterus and a pregnancy mass located at the anterior uterine wall. The gestational sac measuring at 16 mm × 20 mm × 20mm in size contained a yolk sac without visible embryo, corresponding to gestational age of 5–6 weeks (Fig.  1 ). Other laboratory tests were completely normal. Following consultation, an intramural pregnancy (IP) was identified. Fig. 1 Ultrasound scan before surgical intervention show the intramural pregnancy mass measuring at 16 × mm 20 mm × 20 mm with yolk sac structure and non-visible embryo, corresponding to gestation of 5–6 weeks. The mass is detected with proliferative vascular grade 4 on Doppler signal Ultrasound scan before surgical intervention show the intramural pregnancy mass measuring at 16 × mm 20 mm × 20 mm with yolk sac structure and non-visible embryo, corresponding to gestation of 5–6 weeks. The mass is detected with proliferative vascular grade 4 on Doppler signal Accordingly, the patient underwent laparoscopic surgery for pregnancy mass resection. Upon laparoscopy, intraoperative findings revealed an abnormally purplish blue-colored mass protruding out from the uterine surface measuring 1 cm × 2 cm. The bulging mass located between the anterior surface of the uterus and the right cornual site, about 1–2 cm from the round ligation. The bilateral ovaries were in a grossly normal appearance, and the right fallopian tube was absent due to previous salpingectomy. No active bleeding was found in the pelvic cavity. Under guidance of ultrasound, the mass was determined accurately. A fusiform incision was made using a coagulation hook, which resulted in chorionic villous tissues bulging out. Then, the trophoblastic tissue was resected completely, the hemostatic procedure was performed, and two uterine myometrial edges were sutured continuously (Fig.  2 A–D and Supplementary Video 1–3). Before resection, the team performed a string suture around the IP mass using V-Loc barbed suture to avoiding bleeding during resective procedure. The specimen was placed in a bag and completely removed from the ancillary port. Total blood loss was approximately 10 mL. The specimen was sent for histopathological examination and trophoblastic tissue was confirmed (Fig.  3 ). The serum β-hCG level dropped to 1989 mUI/mL after 48 hours of operation. Three days after the operation, the patient was uneventfully discharged and did not require further treatment. Fig. 2 Intraoperative photos of the present case show: A confirmation of intramural gestational sac located at the anterior uterine wall. B Determination of intramural pregnancy (IP) mass and performing a peripheral suture before excision. C Removal of trophoblastic tissue completely. D Hemostatic procedure by bipolar coagulation Fig. 3 Histopathological endpoint confirms smooth muscle, decidua, and placental villi from relevant specimen (hematoxylin and eosin staining, 10 × and 40 ×, respectively) Intraoperative photos of the present case show: A confirmation of intramural gestational sac located at the anterior uterine wall. B Determination of intramural pregnancy (IP) mass and performing a peripheral suture before excision. C Removal of trophoblastic tissue completely. D Hemostatic procedure by bipolar coagulation Histopathological endpoint confirms smooth muscle, decidua, and placental villi from relevant specimen (hematoxylin and eosin staining, 10 × and 40 ×, respectively) Until writing this report, the patient was monitored without later complications. Repeated ultrasound shows no abnormal mass and her β-hCG level was negative. The patient thanks the team for saving her future fertility.

Additional file 1. Supplementary Video 1. Ultrasound guidance was performed during laparoscopy by sonographist Additional file 2. Supplementary Video 2. Determination, string suture performance, and excision of intramural pregnancy mass. Additional file 3. Supplementary Video 3. Resection and hemostasis after removal of the trophoblastic tissue Additional file 1. Supplementary Video 1. Ultrasound guidance was performed during laparoscopy by sonographist Additional file 2. Supplementary Video 2. Determination, string suture performance, and excision of intramural pregnancy mass. Additional file 3. Supplementary Video 3. Resection and hemostasis after removal of the trophoblastic tissue