Introduction: Conjoined twins are an extremely rare occurrence registered in 1:50,000 to 1:100,000 live births. Due to the increased risk of perinatal morbidity and mortality it is crucial to do the prenatal evaluation and early diagnosis of conjoined twins by ultrasound scan in the first trimester. Early diagnosis in the first trimester gives the parents an option of safe termination of pregnancy.
Case report: A 27-year-old G2P1L1 female was referred to our department for routine first trimester antenatal ultrasound at 9 weeks 4 days according to last menstrual period (LMP). Ultrasound examination detected a monochorionic-monoamniotic twin pregnancy. The two fetuses were seen in a face-to-face fixed position with two separate fetal heads and chests seen. Two separate hearts were seen. The twins were found to be joined at the lower abdomen and pelvis. Based on ultrasound findings ischiopagus conjoined twins diagnosis was made. Parents were counseled and they opted for termination of pregnancy.
Conclusion: Conjoined twins are a very rare complication of monoamniotic-monochorionic pregnancies. Diagnosis on antenatal ultrasound can be made, if in a twin pregnancy, both fetuses persistently maintain a fixed position relative to each other. Early antenatal diagnosis by ultrasound gives the parents a chance to choose an option of safe termination.
Nahar N, Khan N, Islam SM, et al. Conjoined twins with single heart and liver—a case report. Mymensingh Med J 2015;24(1):172–176. PMID: 25725685.
Osmanağaoğlu MA, Aran T, Güven S, et al. Thoracopagus conjoined twins: a case report. ISRN Obstet Gynecol 2011:238360. DOI: 10.5402/2011/238360
Ernst A, Schlattmann P, Waldfahrer F, et al. Die Behandlung des M. Menière mit Betahistin: Kritische Anmerkungen zur BEMED-Studie. Laryngorhinootologie 2017;96(8):519–521. DOI: 10.1136/fetalneonatal-2012-301809.62
Lumme RH, Saarikoski SV. Monoamniotic twin pregnancy. Acta Genet Med Gemellol (Roma) 35(1-2):99–105. DOI: 10.1017/s0001566000006309
Zikulnig L, Hecher K, Bregenzer T, et al. Prognostic factors in severe twin-twin transfusion syndrome treated by endoscopic laser surgery. Ultrasound Obstet Gynecol 1999;14(6):380– 387. DOI: 10.1046/j.1469-0705.1999.14060380.x
Kavecan I, Obrenovic M, Privrodski JJ, et al. Parasitic Twin Presenting Rudimentary Upper Limbs Causes a Unique Spectrum of Anomalies of Autosite. Balkan Med J 2018;35(6):445–446. DOI: 10.4274/balkanmedj.2018.0781
Seo JW, Lee YS, Chi JG. Cross-sectional illustration on major types of conjoined twins. J Korean Med Sci 1988;3(1):19–25. DOI: 10.3346/jkms.1918.104.22.168
Chiu CT, Hou SH, Lai HS, et al. Separation of thoracopagus conjoined twins. A case report. J Cardiovasc Surg (Torino) 1994;35(5):459–462. PMID: 7995841.
Liu H, Deng C, Hu Q, et al. Conjoined twins in dichorionic diamniotic triplet pregnancy: a report of three cases and literature review. BMC Pregnancy Childbirth 2021;21(1):687. DOI: 10.1186/s12884-021-04165-x
Spencer R. Theoretical and analytical embryology of conjoined twins. Part I: embryogenesis. Clin Anat 2000;13(1):36–53. DOI: 10.1002/(SICI)1098-2353(2000)13:1<36::AID-CA5>3.0.CO;2-3
Czyz W, Morahan JM, Ebers GC, et al. Genetic, environmental and stochastic factors in monozygotic twin discordance with a focus on epigenetic differences. BMC Med 2012;10:93. DOI: 10.1186/1741-7015-10-93
Tannuri AC, Batatinha JA, Velhote MC, et al. Conjoined twins: twenty years’ experience at a reference center in Brazil. Clinics (Sao Paulo) 2013;68(3):371–377. DOI: 10.6061/clinics/2013(03)oa14
Cuillier F, Dillon KC, Grochal F, et al. Conjoined twins: what ultrasound may add to management. J Prenat Med 2012;6(1):4–6. PMID: 22905303.
Alkhateeb M, Mashaqbeh M, Magableh S, et al. Early prenatal diagnosis of thoracopagus twins by ultrasound. Acta Inform Med 2015;23(1):60–2. DOI: 10.5455/aim.2015.23.60-62
Pajkrt E, Jauniaux E. First-trimester diagnosis of conjoined twins. Prenat Diagn 2005;25(9):820–826. DOI: 10.1002/pd.1267
Brizot ML, Liao AW, Lopes LM, et al. Conjoined twins pregnancies: experience with 36 cases from a single center. Prenat Diagn 2011;31(12):1120–1125. DOI: 10.1002/pd.2843
Saw PE, Jiang S. The significance of interdisciplinary integration in academic research and application. BIO Integr 2020;1(1):2–5. DOI: 10.15212/bioi-2020-0005
Kirtan K, Doopadapalli D, Shailaja N, et al. An interesting case of undiagnosed conjoined twins. Donald School J Ultrasound Obstet Gynecol 2015;9(3):327–330. DOI: 10.5005/jp-journals-10009-1419