Donald School Journal of Ultrasound in Obstetrics and Gynecology

Register      Login

VOLUME 16 , ISSUE 3 ( July-September, 2022 ) > List of Articles


Key Points and Challenges in Monochorionic Twins

Radu Vladareanu, Costin Berceanu, Razvan Ciortea, Simona Vladareanu

Keywords : Anastomoses, Chorioamnionicity, Complications, Imbalance, Management, Outcome

Citation Information : Vladareanu R, Berceanu C, Ciortea R, Vladareanu S. Key Points and Challenges in Monochorionic Twins. Panam J Trauma Crit Care Emerg Surg 2014; 3 (3):87-92.

DOI: 10.5005/jp-journals-10009-1942

License: CC BY-NC 4.0

Published Online: 18-10-2022

Copyright Statement:  Copyright © 2022; The Author(s).


The frequency of twin gestations has substantially expanded over the past decades, primarily due to maternal age at the time of conception, and the use of assisted reproductive techniques. Twin pregnancies sum up now approximately three percent of all live births. The incidence of monozygotic (MZ) and therefore monochorionic (MC) twins is approximately 1:250 pregnancies. The high risks of monochorionic twins are intensively associated with the angioarchitecture of the common placenta and the presence of interfetal vascular network. Chorionicity is definitely the fundamental element in multiple pregnancy results. Whichever echographic clue suggests the presence of twin gestation, should constitute the investigation of chorionicity a primacy. The proportional rise of the hazard in MC correlated with dichorionic (DC) twins, is of a significance analogous to that of multiple, in comparison with singleton pregnancies. Diagnosing an MC twin pregnancy has essential obstetric significance, part of which impacts the pregnancy and also restrains some therapeutic choices. The aim of this review is to highlight current key points in the diagnosis and management of MC twin pregnancy, on one hand, and also to discuss contemporary challenges regarding this type of multiple pregnancies.

PDF Share
  1. Berceanu C, Mehedinţu C, Berceanu S, et al. Morphological and ultrasound findings in multiple pregnancy placentation. Rom J Morphol Embryol 2018;59(2):435–453.
  2. Simpson LL. What you need to know when managing twins: 10 key facts. Obstet Gynecol Clin North Am 2015;42(2):225–239. DOI: 10.1016/j.ogc.2015.01.002
  3. Hubinont C, Lewi L, Bernard P, et al. Anomalies of the placenta and umbilical cord in twin gestations. Am J Obstet Gynecol 2015;213(4 Suppl):S91–S102. DOI: 10.1016/j.ajog.2015.06.054
  4. Simpson LL. Ultrasound in twins: dichorionic and monochorionic. Semin Perinatol 2013;37(5):348–358. DOI: 10.1053/j.semperi.2013.06.013
  5. Martin JA, Hamilton BE, Osterman MJ. Three decades of twin births in the United States, 1980–2009. NCHS Data Brief 2012;(80):1–8.
  6. Berceanu C, Berceanu S. Placentația în sarcina multiplă. In: Berceanu C, editor. Sarcina multiplă. Editura Medicală Universitară Craiova; 2015; p. 59–74.
  7. Blickstein I. Monozygosity. In: Kurjak A, Chervenak FA. Textbook of Perinatal Medicine Second Edition. Informa Healthcare Abingdon UK; 2006; p. 1552–1559.
  8. Fox H, Sebire NJ. Pathology of the Placenta, 3rd ed. Saunders Elsevier, Philadelphia; 2007;355–384.
  9. Baldwin VJ. Placental pathology and multiple gestation. In: Lewis HL, Perrin E (Eds). Pathology of the Placenta, 2nd Edition, Churchill Livingstone, New York; 1999; p. 213–257.
  10. Cîrstoiu MM, Filipoiu FM, Brătilă E, et al. Morphological study of cephalothoracopagus deradelphus type conjoined twins. A case report. Rom J Morphol Embryol 2016;57(1):249–152.
  11. Hacker NF, Moore GJ, Gambone JC. Essentials of Obstetrics and Gynecology. 4th Edition. Elsevier Saunders, Philadelphia; 2004;183–196.
  12. Feldstein VA, Filly RA. Complications of monochorionic twins. Radiol Clin North Am 2003;41(4):709–727. DOI: 10.1016/s0033-8389(03)00046-0
  13. Bianchi DW, Crombleholme TM, D'Alton ME, et al. Fetology-Diagnosis and Management of the Fetal Patient. 2nd ed. McGraw-Hill Medical, New York; 2010; 810–817.
  14. Machin G, Still K, Lalani T. Correlations of placental vascular anatomy and clinical outcomes in 69 monochorionic twin pregnancies. Am J Med Genet 1996;61(3):229–236. DOI: 10.1002/(SICI)1096-8628(19960122)61:3<229::AID-AJMG6>3.0.CO;2-P
  15. Hack KE, Nikkels PG, Koopman-Esseboom C, et al. Placental characteristics of monochorionic diamniotic twin pregnancies in relation to perinatal outcome. Placenta 2008;29(11):976–981. DOI: 10.1016/j.placenta.2008.08.019
  16. Lopriore E, Deprest J, Slaghekke F, et al. Placental characteristics in monochorionic twins with and without twin anemia-polycythemia sequence. Obstet Gynecol 2008;112(4):753–758. DOI: 10.1097/AOG.0b013e318187e1ff
  17. Berceanu C. Sindromul transfuzor-transfuzat. In: Berceanu C, editor. Sarcina multiplă. Editura Medicală Universitară, Craiova; 2015; p. 167–211.
  18. Engineer N, Fisk N. Multiple Pregnancy. In: Rodeck CH, Whittle MJ, editors.: In Fetal Medicine - Basic Science and Clinical Practice. 2nd ed. Churchill Livingstone Elsevier; 2009; p. 649–677.
  19. Bajoria R, Wigglesworth J, Fisk NM. Angioarchitecture of monochorionic placentas in relation to the twin-twin transfusion syndrome. Am J Obstet Gynecol 1995;172(3):856–863. DOI: 10.1016/0002-9378(95)90011-x
  20. Denbow ML, Cox P, Taylor M, et al. Placental angioarchitecture in monochorionic twin pregnancies: relationship to fetal growth, fetofetal transfusion syndrome, and pregnancy outcome. Am J Obstet Gynecol 2000;182(2):417–426. DOI: 10.1016/s0002-9378(00)70233-x
  21. Taylor MJO, Fisk NM. Management of Twin-Twin Transfusion Syndrome. In: Blickstein I, Keith LG, editors. Multiple Pregnancy - Epidemiology, Gestation & Pregnancy outcome. 2nd Edition. Informa Healthcare, Taylor & Francis Group, Colchester, Essex, UK; 2010; p. 552–570.
  22. Umur A, van Gemert MJ, Nikkels PG. Monoamniotic-versus diamniotic-monochorionic twin placentas: anastomoses and twin-twin transfusion syndrome. Am J Obstet Gynecol 2003;189(5):1325–1329. DOI: 10.1067/s0002-9378(03)00811-1
  23. Morin L, Lim K. Diagnostic Imaging Committee, et al. Ultrasound in twin pregnancies. J Obstet Gynaecol Can 2011;33(6):643–656. DOI: 10.1016/S1701-2163(16)34916-7
  24. Bora SA, Papageorghiou AT, Bottomley C, et al. Reliability of transvaginal ultrasonography at 7–9 weeks’ gestation in the determination of chorionicity and amnionicity in twin pregnancies. Ultrasound Obstet Gynecol 2008;32(5):618–621. DOI: 10.1002/uog.6133
  25. Berceanu C, Berceanu S. Diagnosticul corionicității şi amnionicității. In: Berceanu C, editor. Sarcina multiplă. Editura Medicală Universitară Craiova; 2015; p. 75–104.
  26. Timor-Tritsch IE, Monteagudo A. Diagnosis of Chorionicity and Amnionicity. In: Blickstein I, Keith LG, editors. Multiple Pregnancy - Epidemiology, Gestation & Perinatal outcome. 2nd Edition. Informa Healthcare, Abingdon, UK; 2010; p. 291–307.
  27. Carroll SG, Soothill PW, Abdel-Fattah SA, et al. Prediction of chorionicity in twin pregnancies at 10–14 weeks of gestation. BJOG 2002;109(2):182–186. DOI: 10.1111/j.1471-0528.2002.01172.x
  28. Devlieger RG, Demeyere T, Deprest JA, et al. Ultrasound determination of chorionicity in twin pregnancy: accuracy and operator experience. Twin Res 2001;4(4):223–226. DOI: 10.1375/1369052012425
  29. Sebire NJ, Souka A, Skentou H, et al. First trimester diagnosis of monoamniotic twin pregnancies. Ultrasound Obstet Gynecol 2000;16(3):223–225. DOI: 10.1046/j.1469-0705.2000.00229.x
  30. Berceanu C, Berceanu S. Gemenii monoamniotici Complicațiile şi prognosticul monoamnionicității. In: Berceanu C, editor. Sarcina multiplă, Editura Medicală Universitară, Craiova; 2015; p. 226–245.
  31. al-Kouatly HB, Skupski DW. Intrauterine sling: a complication of the stuck twin syndrome. Ultrasound Obstet Gynecol 1999;14(6):419–421. DOI: 10.1046/j.1469-0705.1999.14060419.x
  32. Bilardo CM, Arabin B. Monoamniotic Twins. In: Blickstein I, Keith LG, editors. Multiple Pregnancy - Epidemiology, Gestation & Perinatal outcome. 2nd ed. Informa Healthcare, Abingdon, UK; 2010; p. 574–582.
  33. Ishii K. Prenatal diagnosis and management of monoamniotic twins. Curr Opin Obstet Gynecol 2015;27(2):159–164. DOI: 10.1097/GCO.0000000000000160
  34. Egan JFX, Borgida AF. Ultrasound Evaluation of Multiple Pregnancies. In: Callen PW, editor. Ultrasonography in Obstetrics and Gynecology. 5th ed. Saunders Elsevier, Philadelphia; 2008; p. 266–296.
  35. Fuchs KM, D'Alton ME. Monochorionic Monoamniotic Twin Gestations. In: Copel JA, D'Alton ME, Gratcos E, Platt LD, Tutschek B, Feltovich H, Odibo AO. Obstetric Imaging. Elsevier Saunders, Philadelphia; 2012; p. 710–714.
  36. Habli M. Multiple Gestation. In: Kline-Fath BM, Bulas DI, Bahado-Singh R, editors. Fundamental and Advanced Fetal Imaging: Ultrasound and MRI. Wolters Kluwer Health, Philadelphia; 2015; p. 315–344.
  37. Schoenwolf GC, Bleyl SB, Brauer PR, et al. Larsen's Human Embryology. 5th ed. Churchill Livingstone, Philadelphia; 2015; 82–107.
  38. Levi CS, Lyons EA, Dashefsky SM, et al. Yolk sac number, size and morphologic features in monochorionic monoamniotic twin pregnancy. Can Assoc Radiol J 1996;47(2):98–100.
  39. Fisk NM, Duncombe GJ, Sullivan MH. The basic and clinical science of twin-twin transfusion syndrome. Placenta 2009;30(5):379–390. DOI: 10.1016/j.placenta.2009.02.005
  40. Bamberg C, Hecher K. Update on twin-to-twin transfusion syndrome. Best Pract Res Clin Obstet Gynaecol 2019;58:55–65. DOI: 10.1016/j.bpobgyn.2018.12.011
  41. Society for Maternal-Fetal Medicine, Simpson LL. Twin-twin transfusion syndrome. Am J Obstet Gynecol. 2013;208(1):3–18. DOI: 10.1016/j.ajog.2012.10.880
  42. Oepkes D, Sueters M. Antenatal fetal surveillance in multiple pregnancies. Best Pract Res Clin Obstet Gynaecol 2017;38:59–70. DOI: 10.1016/j.bpobgyn.2016.09.004
  43. Quintero RA, Morales WJ, Allen MH, et al. Staging of twin-twin transfusion syndrome. J Perinatol 1999;19(8 Pt 1):550–555. DOI: 10.1038/
  44. Khalil A, Rodgers M, Baschat A, et al. ISUOG practice guidelines: role of ultrasound in twin pregnancy. Ultrasound Obstet Gynecol 2016;47(2):247–263. DOI: 10.1002/uog.15821
  45. O'Donoghue K, Cartwright E, Galea P, et al. Stage I twin-twin transfusion syndrome: rates of progression and regression in relation to outcome. Ultrasound Obstet Gynecol 2007;30(7):958–964. DOI: 10.1002/uog.5189
  46. Dickinson JE, Evans SF. The progression of disease stage in twin-twin transfusion syndrome. J Matern Fetal Neonatal Med 2004;16(2):95–101. DOI: 10.1080/14767050400004692
  47. Lewi L, Jani J, Cannie M, et al. Intertwin anastomoses in monochorionic placentas after fetoscopic laser coagulation for twin-to-twin transfusion syndrome: is there more than meets the eye? Am J Obstet Gynecol 2006;194(3):790–795. DOI: 10.1016/j.ajog.2005.08.062
  48. Senat MV, Deprest J, Boulvain M, et al. Endoscopic laser surgery versus serial amnioreduction for severe twin-to-twin transfusion syndrome. N Engl J Med 2004;351(2):136–44. DOI: 10.1056/NEJMoa032597
  49. Salomon LJ, Ortqvist L, Aegerter P, et al. Long-term developmental follow-up of infants who participated in a randomized clinical trial of amniocentesis vs laser photocoagulation for the treatment of twin-to-twin transfusion syndrome. Am J Obstet Gynecol 2010;203(5):444.e1–447.e1. DOI: 10.1016/j.ajog.2010.08.054
  50. Lopriore E, Middeldorp JM, Oepkes D, et al. Residual anastomoses after fetoscopic laser surgery in twin-to-twin transfusion syndrome: frequency, associated risks and outcome. Placenta 2007;28(2-3):204–208. DOI: 10.1016/j.placenta.2006.03.005
  51. Quintero RA, Chmait RH, Bornick PW, et al. Trocar-assisted selective laser photocoagulation of communicating vessels: a technique for the laser treatment of patients with twin-twin transfusion syndrome with inaccessible anterior placentas. J Matern Fetal Neonatal Med 2010;23(4):330–334. DOI: 10.3109/14767050903177177
  52. Slaghekke F, Lopriore E, Lewi L, et al. Fetoscopic laser coagulation of the vascular equator versus selective coagulation for twin-to-twin transfusion syndrome: an open-label randomised controlled trial. Lancet 2014;383(9935):2144–2151. DOI: 10.1016/S0140-6736(13)62419-8
  53. Tollenaar LSA, Slaghekke F, Lewi L, et al. Spontaneous twin anemia polycythemia sequence: diagnosis, management, and outcome in an international cohort of 249 cases. Am J Obstet Gynecol 2021;224(2):213.e1–213.e11. DOI: 10.1016/j.ajog.2020.07.041
  54. Slaghekke F, Kist WJ, Oepkes D, et al. Twin anemia-polycythemia sequence: diagnostic criteria, classification, perinatal management and outcome. Fetal Diagn Ther 2010;27(4):181–190. DOI: 10.1159/000304512
  55. Bae JY, Oh JJ, Hong SY. Prenatal diagnosis of spontaneous twin anemia-polycythemia sequence and postnatal examination of placental vascular anastomoses. Obstet Gynecol Sci 2016;59(6):539–543. DOI: 10.5468/ogs.2016.59.6.539
  56. Groussolles M, Sartor A, Connan L, et al. Evolution of middle cerebral artery peak systolic velocity after a successful laser procedure for iatrogenic twin anemia-polycythemia sequence. Ultrasound Obstet Gynecol 2012;39(3):354–356. DOI: 10.1002/uog.8999
  57. Lewi L, Jani J, Blickstein I, et al. The outcome of monochorionic diamniotic twin gestations in the era of invasive fetal therapy: a prospective cohort study. Am J Obstet Gynecol 2008;199(5):514.e1–518.e1. DOI: 10.1016/j.ajog.2008.03.050
  58. Lopriore E, Slaghekke F, Middeldorp JM, et al. Residual anastomoses in twin-to-twin transfusion syndrome treated with selective fetoscopic laser surgery: localization, size, and consequences. Am J Obstet Gynecol 2009;201(1):66.e1–66.e4. DOI: 10.1016/j.ajog.2009.01.010
  59. Habli M, Bombrys A, Lewis D, et al. Incidence of complications in twin-twin transfusion syndrome after selective fetoscopic laser photocoagulation: a single-center experience. Am J Obstet Gynecol 2009;201(4):417.e1–417.e7. DOI: 10.1016/j.ajog.2009.07.046
  60. Slaghekke F, Kist WJ, Oepkes D, et al. TAPS and TOPS: two distinct forms of feto-fetal transfusion in monochorionic twins. Z Geburtshilfe Neonatol 2009;213(6):248–254. DOI: 10.1055/s-0029-1241884
  61. Khalil A, Gordijn S, Ganzevoort W, et al. Consensus diagnostic criteria and monitoring of twin anemia-polycythemia sequence: Delphi procedure. Ultrasound Obstet Gynecol 2020;56(3):388–394. DOI: 10.1002/uog.21882
  62. Hill KM, Masoudian P, Fung-Kee-Fung K, et al. Intrauterine interventions for the treatment of twin anemia-polycythemia sequence: a systematic review. J Obstet Gynaecol Can 2019;41(7):981–991. DOI: 10.1016/j.jogc.2018.04.005
  63. Herway C, Johnson A, Moise K, et al. Fetal intraperitoneal transfusion for iatrogenic twin anemia-polycythemia sequence after laser therapy. Ultrasound Obstet Gynecol 2009;33(5):592–594. DOI: 10.1002/uog.6334
  64. Tollenaar LS, Slaghekke F, Middeldorp JM, et al. Twin anemia polycythemia sequence: current views on pathogenesis, diagnostic criteria, perinatal management, and outcome. Twin Res Hum Genet 2016;19(3):222–233. DOI: 10.1017/thg.2016.18
  65. Ishii K, Murakoshi T, Matsushita M, et al. Transitory increase in middle cerebral artery peak systolic velocity of recipient twins after fetoscopic laser photocoagulation for twin-twin transfusion syndrome. Fetal Diagn Ther 2008;24(4):470–473. DOI: 10.1159/000178531
  66. Vitucci A, Fichera A, Fratelli N, et al. Twin reversed arterial perfusion sequence: current treatment options. Int J Womens Health 2020;12:435–443. DOI: 10.2147/IJWH.S214254
  67. van Gemert MJ, van den Wijngaard JP, Vandenbussche FP. Twin reversed arterial perfusion sequence is more common than generally accepted. Birth Defects Res A Clin Mol Teratol 2015;103(7):641–643. DOI: 10.1002/bdra.23405
  68. Berceanu C. Managementul complicatiilor specifice in sarcina gemelara monocorionica In: Berceanu C, editor. Sarcina multiplă. Editura Medicală Universitară, Craiova; 2015; p. 314–334.
  69. Ghartey K, Miller RS, Simpson L. Twin Reversed Arterial Perfusion Sequence. In: Copel, D'Alton, Gratcos, Platt, Tutschek, Feltovich, Odibo. Obstetric Imaging. Elsevier Saunders, Philadelphia; 2012; p. 732–736.
  70. Ruiz-Cordero R, Birusingh RJ, Pelaez L, et al. Twin reversed arterial perfusion sequence (TRAPS): an illustrative series of 13 cases. Fetal Pediatr Pathol 2016;35(2):63–80. DOI: 10.3109/15513815.2015.1131785
  71. Wong AE, Sepulveda W. Acardiac anomaly: current issues in prenatal assessment and treatment. Prenat Diagn 2005;25(9):796–806. DOI: 10.1002/pd.1269
  72. Hartge DR, Weichert J. Prenatal diagnosis and outcome of multiple pregnancies with reversed arterial perfusion (TRAP-sequence). Arch Gynecol Obstet 2012;286(1):81–88. DOI: 10.1007/s00404-012-2283-9
  73. Moore TR, Gale S, Benirschke K. Perinatal outcome of forty-nine pregnancies complicated by acardiac twinning. Am J Obstet Gynecol 1990;163(3):907–912. DOI: 10.1016/0002-9378(90)91094-s
  74. Jelin E, Hirose S, Rand L, et al. Perinatal outcome of conservative management versus fetal intervention for twin reversed arterial perfusion sequence with a small acardiac twin. Fetal Diagn Ther 2010;27(3):138–141. DOI: 10.1159/000295176
  75. Marella D, Prefumo F, Valcamonico A, et al. Polyhydramnios in sac of parasitic twin: atypical manifestation of twin reversed arterial perfusion sequence. Ultrasound Obstet Gynecol 2015;45(6):752–753. DOI: 10.1002/uog.14766
  76. Dhanju G, Breddam A. Twin reversed arterial perfusion (TRAP) sequence: a case report and a brief literature review. Radiol Case Rep 2022;17(5):1682–1691. DOI: 10.1016/j.radcr.2022.02.057
  77. Berg C, Holst D, Mallmann MR, et al. Early vs late intervention in twin reversed arterial perfusion sequence. Ultrasound Obstet Gynecol 2014;43(1):60–64. DOI: 10.1002/uog.12578
  78. Pepe F, Teodoro MC, Luca C, et al. Conservative management in a case of uncomplicated trap sequence: a case report and brief literature review. J Prenat Med 2015;9(3-4):29–34. DOI: 10.11138/jpm/2015.9.3.029
  79. Chaveeva P, Poon LC, Sotiriadis A, et al. Optimal method and timing of intrauterine intervention in twin reversed arterial perfusion sequence: case study and meta-analysis. Fetal Diagn Ther 2014;35(4):267–279. DOI: 10.1159/000358593
  80. Lewi L, Valencia C, Gonzalez E, et al. The outcome of twin reversed arterial perfusion sequence diagnosed in the first trimester. Am J Obstet Gynecol 2010;203(3):213.e1–213.e4. DOI: 10.1016/j.ajog.2010.04.018
  81. Stephenson CD, Temming LA, Pollack R, et al. Microwave ablation for twin-reversed arterial perfusion sequence: a novel application of technology. Fetal Diagn Ther 2015;38(1):35–40. DOI: 10.1159/000369384
  82. Livingston JC, Lim FY, Polzin W, et al. Intrafetal radiofrequency ablation for twin reversed arterial perfusion (TRAP): a single-center experience. Am J Obstet Gynecol 2007;197(4):399.e1–399.e3. DOI: 10.1016/j.ajog.2007.07.051
  83. Pagani G, D'Antonio F, Khalil A, et al. Intrafetal laser treatment for twin reversed arterial perfusion sequence: cohort study and meta-analysis. Ultrasound Obstet Gynecol 2013;42(1):6–14. DOI: 10.1002/uog.12495
  84. Seo K, Ichizuka K, Okai T, et al. Treatment of twin-reversed arterial perfusion sequence using high-intensity focused ultrasound. Ultrasound Obstet Gynecol 2019;54(1):128–134. DOI: 10.1002/uog.20101
  85. Ozawa K, Wada S, Muromoto J, et al. Long-term neurodevelopmental outcomes of the pump twin in twin reversed arterial perfusion sequence treated by radiofrequency ablation. Prenat Diagn 2021;41(12):1575–1581. DOI: 10.1002/pd.6048
  86. Sugibayashi R, Ozawa K, Sumie M, et al. Forty cases of twin reversed arterial perfusion sequence treated with radio frequency ablation using the multistep coagulation method: a single-center experience. Prenat Diagn 2016;36(5):437–443. DOI: 10.1002/pd.4800
  87. Van Mieghem T, Abbasi N, Shinar S, et al. Monochorionic monoamniotic twin pregnancies. Am J Obstet Gynecol MFM 2022;4(2S):100520. DOI: 10.1016/j.ajogmf.2021.100520
  88. Post A, Heyborne K. Managing monoamniotic twin pregnancies. Clin Obstet Gynecol 2015;58(3):643–653. DOI: 10.1097/GRF.0000000000000118
  89. Monteiro J, Derom C, Vlietinck R, et al. Commitment to X inactivation precedes the twinning event in monochorionic MZ twins. Am J Hum Genet 1998;63(2):339–346. DOI: 10.1086/301978
  90. Hack KE, Derks JB, Schaap AH, et al. Perinatal outcome of monoamniotic twin pregnancies. Obstet Gynecol 2009;113(2 Pt 1):353–360. DOI: 10.1097/AOG.0b013e318195bd57
  91. Fenton C, Reidy K, Demyanenko M, et al. The significance of yolk sac number in monoamniotic twins. Fetal Diagn Ther 2015;46(3):193–199. DOI: 10.1159/000496204
  92. Li L, He Z, Huang X, et al. Chromosomal abnormalities detected by karyotyping and microarray analysis in twins with structural anomalies. Ultrasound Obstet Gynecol 2020;55(4):502–509. DOI: 10.1002/uog.20287
  93. Van Mieghem T, De Heus R, Lewi L, et al. Prenatal management of monoamniotic twin pregnancies. Obstet Gynecol 2014;124(3):498–506. DOI: 10.1097/AOG.0000000000000409
  94. Kalafat E, Shirazi A, Thilaganathan B, et al. The role of aspirin in prevention of preeclampsia in twin pregnancies: does the dose matter? Am J Obstet Gynecol 2020;223(3):457–458. DOI: 10.1016/j.ajog.2020.03.005
  95. MONOMONO Working Group. Inpatient vs outpatient management and timing of delivery of uncomplicated monochorionic monoamniotic twin pregnancy: the MONOMONO study. Ultrasound Obstet Gynecol 2019;53(2):175–183. DOI: 10.1002/uog.19179
  96. Syngelaki A, Cimpoca B, Litwinska E, et al. Diagnosis of fetal defects in twin pregnancies at routine 11–13–week ultrasound examination. Ultrasound Obstet Gynecol 2020;55(4):474–481. DOI: 10.1002/uog.21938
  97. Greco PS, Pitts D, Weadock WJ, et al. Conjoined twins: an obstetrician's guide to prenatal care and delivery management. J Perinatol 2021;41(10):2424–2431. DOI: 10.1038/s41372-021-01107-5
  98. Spitz L. Conjoined twins. Prenat Diagn 2005;25(9):814–819. DOI: 10.1002/pd.1268
  99. Wataganara T, Ruangvutilert P, Sunsaneevithayakul P, et al. Three-dimensional ultrasound for prenatal assessment of conjoined twins: additional advantages? J Perinat Med 2017;45(6):667–691. DOI: 10.1515/jpm-2016-0381
  100. Thomas A, Johnson K, Placencia FX. An ethically-justifiable, practical approach to decision-making surrounding conjoined-twin separation. Semin Perinatol 2018;42(6):381–385. DOI: 10.1053/j.semperi.2018.07.016
  101. Marty CM, Carter BS. Ethics and palliative care in the perinatal world. Semin Fetal Neonatal Med 2018;23(1):35–38. DOI: 10.1016/j.siny.2017.09.001
  102. O'Brien P, Nugent M, Khalil A. Prenatal diagnosis and obstetric management. Semin Pediatr Surg 2015;24(5):203–206. DOI: 10.1053/j.sempedsurg.2015.06.002
  103. Mitchell T, Cheng E, Jolley J, et al. Successful induction of labor of late-second-trimester conjoined twins: an alternative to hysterotomy. Obstet Gynecol 2014;123(2 Pt 2 Suppl 2):469–472. DOI: 10.1097/AOG.0000000000000038
  104. Landy HJ, Keith LG. The Vanishing fetus. In: Blickstein I, Keith LG, editors. Multiple Pregnancy - Epidemiology, Gestation & Pregnancy outcome. 2nd ed. Informa Healthcare, Taylor & Francis Group, Colchester, Essex, UK; 2010: p. 108–112.
  105. Evron E, Sheiner E, Friger M, et al. Vanishing twin syndrome: is it associated with adverse perinatal outcome? Fertil Steril 2015;103(5):1209–1214. DOI: 10.1016/j.fertnstert.2015.02.009
  106. Almog B, Levin I, Wagman I, et al. Adverse obstetric outcome for the vanishing twin syndrome. Reprod Biomed Online 2010;20(2):256–260. DOI: 10.1016/j.rbmo.2009.11.015
  107. Buca D, Pagani G, Rizzo G, et al. Outcome of monochorionic twin pregnancy with selective intrauterine growth restriction according to umbilical artery Doppler flow pattern of smaller twin: systematic review and meta-analysis. Ultrasound Obstet Gynecol 2017;50(5):559–568. DOI: 10.1002/uog.17362
  108. Gratacós E, Lewi L, Muñoz B, et al. A classification system for selective intrauterine growth restriction in monochorionic pregnancies according to umbilical artery Doppler flow in the smaller twin. Ultrasound Obstet Gynecol 2007;30(1):28–34. DOI: 10.1002/uog.4046
  109. Kanda M, Noguchi S, Yamamoto R, et al. Perinatal outcomes of intrauterine transfusion for the surviving twin in monochorionic twin gestation involving a single fetal demise. J Obstet Gynaecol Res 2020;46(8):1319–1325. DOI: 10.1111/jog.14338
  110. Morris RK, Mackie F, Garces AT, et al. The incidence, maternal, fetal and neonatal consequences of single intrauterine fetal death in monochorionic twins: A prospective observational UKOSS study. PLoS One 2020;15(9):e0239477. DOI: 10.1371/journal.pone.0239477
  111. Mackie FL, Morris RK, Kilby MD. Fetal brain injury in survivors of twin pregnancies complicated by demise of one twin: a review. Twin Res Hum Genet 2016;19(3):262–267. DOI: 10.1017/thg.2016.39
  112. Ochsenbein-Kölble N. Twin pregnancies. Ultraschall Med 2021;42(3):246–269. DOI: 10.1055/a-1344-4812
  113. Lewi L. Monochorionic diamniotic twins: what do I tell the prospective parents? Prenat Diagn 2020;40(7):766–775. DOI: 10.1002/pd.5705
  114. Lu J, Cheng YKY, Ting YH, et al. Pitfalls in assessing chorioamnionicity: novel observations and literature review. Am J Obstet Gynecol 2018;219(3):242–254. DOI: 10.1016/j.ajog.2018.02.010
  115. Lewi L, Blickstein I, Van Schoubroeck D, et al. Diagnosis and management of heterokaryotypic monochorionic twins. Am J Med Genet A 2006;140(3):272–275. DOI: 10.1002/ajmg.a.31052
  116. Khalil A, Beune I, Hecher K, et al. Consensus definition and essential reporting parameters of selective fetal growth restriction in twin pregnancy: a Delphi procedure. Ultrasound Obstet Gynecol 2019;53(1):47–54. DOI: 10.1002/uog.19013
  117. Yamashita A, Ishii K, Hidaka N, et al. Monochorionic monozygotic twin pregnancy complicated with twin-twin transfusion syndrome presenting with an obvious lambda sign in the first trimester. Fetal Diagn Ther 2015;37(2):154–156. DOI: 10.1159/000367969
  118. Tollenaar LSA, Lopriore E, Faiola S, et al. Post-laser twin anemia polycythemia sequence: diagnosis, management, and outcome in an international cohort of 164 cases. J Clin Med 2020;9(6):1759. DOI: 10.3390/jcm9061759
PDF Share
PDF Share

© Jaypee Brothers Medical Publishers (P) LTD.