Case Report
HJOG 2025, 24 (1), 62-65| doi: 10.33574/hjog.0585
Chidinma Magnus Nwogu1, Ayodeji Kayode Adefemi2, Aloy Okechukwu Ugwu3
1Kingswill Advanced Specialist Hospital, Lagos, Nigeria
2Lagos State University Teaching Hospital, Ikeja, Lagos, Nigeria
3Lagos University Teaching Hospital, Idi-Araba, Lagos, Nigeria
Correspondence: Aloy Okechukwu Ugwu, Department of Obstetrics and Gynaecology, Lagos University Teaching Hospital, Lagos, Nigeria
Abstract
Intramyometrial ectopic pregnancy is a very rare subset of ectopic pregnancy. It occurs when a pregnancy implants within the myometrium. The risk factors for this type of extrauterine pregnancy include previous history of uterine trauma such as myomectomy, caesarean section and dilatation and curettage. It can present with catastrophic outcome due to uterine rupture if undetected early. Prompt diagnosis allows for preservation of fertility. We present a 42-year-old lady with an intramyometrial ectopic pregnancy following an in-vitro fertilization and difficult embryo transfer who was managed successfully in our facility.
Keywords: ART, intramyometrial ectopic pregnancy, previous myomectomy, in-vitro-fertilization
Introduction
Extra uterine gestation occurs when there is implantation of the blastocyst in other sites outside the endometrial cavity.1, 2 The continued availability of assisted conception in many countries has inadvertently increased the incidence of ectopic pregnancies.1, 3 Most of these extra uterine gestations occur in the Fallopian tubes. However, there are also some uncommon sites of ectopic pregnancies some of which are becoming popular with increased use of invitro fertilization and embryo transfer. These sites include previous caesarean section scars, intramyometrial, cervix, interstitial, intra-ligamentry (between the two folds of broad ligament), peritoneal cavity, ovary, and even hepatic ectopic gestations. 1-4
Intramyometrial ectopic pregnancy, otherwise referred to intramural pregnancy, is a rare form of ectopic gestation. It accounts for less than 1% of extra uterine pregnancies. It is a type of pregnancy that results when a gestational sac is seen entirely in the myometrium. Several risk factors have been suggested for this type of pregnancy, these risk factors include, previous myomectomy, previous caesarean section, dilatation and curettage, vigorous manual vacuum aspiration, manual removal of the placenta, difficult embryo transfer during invitro-fertilization with creation of a fistulous tract and previous metroplasty. 5, 6, 7,8
It poses a diagnostic dilemma as most of the symptoms such as abdominal pain, absent menses, malaise, vaginal spotting, and tiredness are also encountered in early pregnancy and other forms of ectopic pregnancy. Intramyometrial ectopic pregnancy can be diagnosed using a pelvic/ transvaginal ultrasound and Magnetic Resonance Imaging (MRI). Just as with other forms of ectopic pregnancy, management options include expectant, surgical and medical treatment. Several surgical options for fertility preservation have been described, this can be done via laparotomy or laparoscopy.6, 7, 8 The index patient had laparotomy and wedge resection. Notwithstanding, hysterectomy for the treatment of intramyometrial ectopic pregnancy has been described because of the intractable bleeding that is occasionally associated with it.7
Case
She was a 42-year-old Para 3 (all alive) lady whose last childbirth was 9 years prior. She desired assisted conception for gender balancing. There was a history of open abdominal myomectomy 14 months prior to presentation during which she was transfused with 3 units of blood. Histology of the post op specimen was not seen as the surgery was done in another hospital prior to presentation. She has also had two previous caesarean sections. She had donor cycle IVF and embryo transfer. She had a difficult mock/ dummy embryo transfer because of suspected adenomyotic area on the fundus of the uterus. Also noticed during the dummy transfer was a suspected sinus tract (confirmed during ultrasound-guided embryo transfer). She had a positive blood pregnancy test 14 days post embryo transfer and was scheduled for pregnancy confirmation ultrasound scan 30 days post embryo transfer. Transvaginal sonography showed a decidualized cystic structure with a fetal pole and cardiac pulsation in the mid posterior myometrium. A second opinion transvaginal ultrasonography on the same day also revealed same findings of an intramyometrial ectopic gestation in the posterior uterine wall. She had a laparotomy and wedge resection of the posterior myometrium with complete removal of trophoblastic tissues. Her post op vital signs were withing normal values. Blood loss was 750mls. She did clinically well and was discharged on the 3rd post operative day.
Figure 1. (a) and (b); Two independent transvaginal sonography of same patient same day showing decidualized gestational sac with fetal pole in posterior myometrium.
Discussion
Intramyometrial ectopic pregnancy is a very rare form of ectopic pregnancy whose risk factors are related to prior uterine trauma.2,4,7 The risk factors seen in the index patient presented were advanced maternal age, invitro- fertilization, and previous uterine surgeries (two caesarean sections and previous myomectomy).
Patients with intramyometrial ectopic pregnancy can be asymptomatic as in the index case, they can also present with lower abdominal pain, vaginal bleeding, absent menses, and a positive pregnancy test.3,4 A greater proportion of the diagnoses are missed pre-operatively. This group of patients are diagnosed intraoperatively.4,5
The use of early ultrasound scan or MRI has been described in the diagnosis of intramyometrial ectopic pregnancy.5, 6 On ultrasound examination, it appears as gestational sac surrounded by myometrium with associated empty endometrial cavity and Fallopian tubes.4
Ultrasound scan differentials include degenerating fibroid, congenital uterine anomaly, or pregnancy in a sacculation or diverticulum, cornual ectopic pregnancy, pregnancy of unknown location and hydatiform mole/choriocarcinoma.3, 4. Our patient was diagnosed following a scheduled ultrasound after embryo transfer.
Magnetic resonance imaging (MRI) is a reliable, non-invasive but more expensive imaging modality, delineating the myometrium surrounding the gestational sac with no communication with the endometrial cavity even more useful when ruptured 2, 3.
The management should be individualized with respect to the time of diagnosis, clinical status, future fertility desire, availability and skill of surgeon.6, 7, 8
In a haemodynamically stable patient with desire to retain fertility, conservative options such as; local administration of potassium chloride or methotrexate or by systemic methotrexate either in single dose or as multiple dose regimen can be employed 2, 3, 4 Non radical surgical management by enucleation or wedge resection with myometrial reconstruction can be performed with or without uterine artery embolization2, 3 The index patient had wedge resection of the intramyometrial ectopic gestation.
Conclusion
Intramyometrial gestation is a very rare type of ectopic gestation. We present a very rare form of ectopic gestation following assisted conception. Prompt use of ultrasound to confirm pregnancy location after invitro fertilization will help in reducing maternal mortality and morbidity that may arise from late diagnosis.
Ethical approval
This study was approved by the research committee of the Kingswill advanced fertility center Lagos, where this patient was managed.
Guarantor
The corresponding author will act as the guarantor for this manuscript.
Disclaimer (artificial intelligence)
We hereby declare that no generative AI technologies such as Large Language Models (ChatGPT, COPILOT, etc.) and text-to-image generators have been used during writing or editing of manuscript.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms for the data to be published.
Acknowledgments
We are also grateful to all our nurses and midwives at Kingswill advanced fertility center, Lagos where this patient was managed for their dedication to duty.
Financial support and sponsorship
None.
Conflicts of interest
None
References
- Ugwu AO, Makwe CC, Omisakin SI, Ani-Ugwu NK, Augustine E, Ojiefoh LG, et al. Successful management of cervical ectopic pregnancy following invitro fertilisation. Hellenic Journal of Obstetrics and Gynecology. 2021 Oct 3;20(4):221–4.
- Katiyar, G., Fernandes, Y., Lawande, S. et al. A rare case of hepatic ectopic pregnancy. Egypt J Radiol Nucl Med 53, 142 (2022). https://doi.org/10.1186/s43055-022-00818-9
- Ade-Ojo IP, Akintayo AA, Afolayan JM, Aduloju OP, Olagbuji BN. Intraligamentary Extrauterine Pregnancy Delivered at Term: A Case Report and Review of Literature. Afr J Reprod Health. 2016 Mar;20(1):104-108. doi: 10.29063/ajrh2016/v20i1.11. PMID: 29553183.
- Koo HS, Bae JY, Kang IS, Koong MK, Kim HO, Cha SH, Choi MH, Kim JY, Yang KM. Laparoscopic management of early primary peritoneal pregnancy: a case report. Clin Exp Reprod Med. 2011 Jun;38(2):109-14. doi: 10.5653/cerm. 2011.38.2.109. Epub 2011 Jun 30. PMID: 22384428; PMCID: PMC3283056.
- Vagg D, Arsala L, Kathurusinghe S, Ang WC. Intramural ectopic pregnancy following myomectomy. J Investig Med High Impact Case Rep. (2018) 6:1–4. 10.1177/2324709618790605.
- Chen X, Gao L, Yu H, Liu M, Kong S, Li S. Intramural Ectopic Pregnancy: Clinical Characteristics, Risk Factors for Uterine Rupture and Hysterectomy. Front Med (Lausanne). 2021 Oct 28; 8:769627. doi: 10.3389/fmed.2021. 769627. PMID: 34778327; PMCID: PMC8583088.
- Kong L, Mao N, Shi Y, Ma H, Xie H. Diagnosis and management of intramural ectopic pregnancy in the second trimester-a case report. BJR Case Rep. 2017 Jun 14;3(4):20160095. doi: 10.1259/bjrcr.20160095. PMID: 30363231; PMCID: PMC6159175.
- Adefemi AK, Nwogu CM, Ugwu AO, Ohagwu IC. A Rare Case of Unilateral Trichorionic Triplet Tubal Ectopic Pregnancy Following In-Vitro Fertilization- A Case Report and Literature Review. West African Journal of Obstetrics and Gynaecology (WAJOG) August 2024; 1(1): 10-13.