• 1
    Hendrix NW, Chauhan SP. Sonographic examination of twins. From first trimester to delivery of second fetus. Obstet Gynecol Clin North Am 1998; 25: 609621.
  • 2
    Cameron AH, Edwards JH, Derom R, Thiery M, Boelaert R. The value of twin surveys in the study of malformations. Eur J Obstet Gynecol Reprod Biol 1983; 14: 347356.
  • 3
    Sepulveda W, Sebire NJ, Hughes K, Odibo A, Nicolaides KH. The lambda sign at 10–14 weeks of gestation as a predictor of chorionicity in twin pregnancies. Ultrasound Obstet Gynecol 1996; 7: 421423.
  • 4
    Little J, Bryan E. Congenital anomalies in twins. Semin Perinatol 1986; 10: 5064.
  • 5
    Patten RM, Mack LA, Harvey D, Cyr DR, Pretorius DH. Disparity of amniotic fluid volume and fetal size: problem of the stuck twin–US studies. Radiology 1989; 172: 153157.
  • 6
    Robertson EG, Neer KJ. Placental injection studies in twin gestation. Am J Obstet Gynecol 1983; 147: 170174.
  • 7
    Sebire NJ, D'Ercole C, Hughes K, Carvalho M, Nicolaides KH. Increased nuchal translucency thickness at 10–14 weeks of gestation as a predictor of severe twin-to-twin transfusion syndrome [see comments]. Ultrasound Obstet Gynecol 1997; 10: 8689.
  • 8
    Senat MV, Deprest J, Boulvain M, Paupe A, Winer N, Ville Y. Endoscopic laser surgery versus serial amnioreduction for severe twin-to-twin transfusion syndrome. N Engl J Med 2004; 351: 136144.
  • 9
    Doyle PE, Beral V, Botting B, Wale CJ. Congenital malformations in twins in England and Wales. J Epidemiol Community Health 1991; 45: 4348.
  • 10
    Chen CJ, Wang CJ, Yu MW, Lee TK. Perinatal mortality and prevalence of major congenital malformations of twins in Taipei city. Acta Genet Med Gemellol (Roma) 1992; 41: 197203.
  • 11
    Myrianthopoulos NC. Congenital malformations: the contribution of twin studies. Birth Defects Orig Artic Ser 1978; 14: 151165.
  • 12
    Schinzel AA, Smith DW, Miller JR. Monozygotic twinning and structural defects. J Pediatr 1979; 95: 921930.
  • 13
    Kallen B. Congenital malformations in twins: a population study. Acta Genet Med Gemellol (Roma) 1986; 35: 167178.
  • 14
    Mastroiacovo P, Castilla EE, Arpino C, Botting B, Cocchi G, Goujard J, Marinacci C, Merlob P, Metneki J, Mutchinick O, Ritvanen A, Rosano A. Congenital malformations in twins: an international study. Am J Med Genet 1999; 83: 117124.
  • 15
    Corney G, MacGillivray I, Campbell DM, Thompson B, Little J. Congenital anomalies in twins in Aberdeen and Northeast Scotland. Acta Genet Med Gemellol (Roma) 1983; 32: 3135.
  • 16
    Snijders RJ, Noble P, Sebire N, Souka A, Nicolaides KH. UK multicentre project on assessment of risk of trisomy 21 by maternal age and fetal nuchal-translucency thickness at 10–14 weeks of gestation. Fetal Medicine Foundation First Trimester Screening Group [see comments]. Lancet 1998; 352: 343346.
  • 17
    The Fetal Medicine Foundation. FMF Regulations for Certification in the 11–14 weeks scan (Registered Charity No.1037116) [Accessed 2004].
  • 18
    Wald NJ, Kennard A, Donnenfeld A, Leck I. Ultrasound scanning for congenital abnormalities. In Antenatal and Neonatal Screening, WaldNJ, LeckI (eds). Oxford University Press: Oxford, 2000; 441470.
  • 19
    Quintero RA, Morales WJ, Allen MH, Bornick PW, Johnson PK, Kruger M. Staging of twin-twin transfusion syndrome. J Perinatol 1999; 19: 550555.
  • 20
    Miller S, Dykes D, Polesky H. A simple salting out procedure for extracting DNA from human nucleated cells. Nucleic Acids Res 1988; 16: 1215.
  • 21
    Kato K, Fujiki K. Multiple births and congenital anomalies in Tokyo Metropolitan Hospitals, 1979–1990. Acta Genet Med Gemellol (Roma) 1992; 41: 253259.
  • 22
    Mavrides E, Cobian-Sanchez F, Tekay A, Moscoso G, Campbell S, Thilaganathan B, Carvalho JS. Limitations of using first-trimester nuchal translucency measurement in routine screening for major congenital heart defects. Ultrasound Obstet Gynecol 2001; 17: 106110.
  • 23
    Hyett JA, Perdu M, Sharland GK, Snijders RS, Nicolaides KH. Increased nuchal translucency at 10–14 weeks of gestation as a marker for major cardiac defects. Ultrasound Obstet Gynecol 1997; 10: 242246.
  • 24
    Bejar R, Vigliocco G, Gramajo H, Solana C, Benirschke K, Berry C, Coen R, Resnik R. Antenatal origin of neurologic damage in newborn infants. II. Multiple gestations. Am J Obstet Gynecol 1990; 162: 12301236.
  • 25
    Sebire NJ, Souka A, Skentou H, Geerts L, Nicolaides KH. Early prediction of severe twin-to-twin transfusion syndrome. Hum Reprod 2000; 15: 20082010.
  • 26
    Matias A, Ramalho C, Montenegro N. Search for hemodynamic compromise at 11–14 weeks in monochorionic twin pregnancy: is abnormal flow in the ductus venosus predictive of twin-twin transfusion syndrome? J Matern Fetal Neonatal Med 2005; 18: 7986.
  • 27
    Marsal K, Persson PH, Larsen T, Lilja H, Selbing A, Sultan B. Intrauterine growth curves based on ultrasonically estimated foetal weights. Acta Paediatr 1996; 85: 843848.