Twin growth discrepancy in early pregnancy
- 11 June 2009
- journal article
- Published by Wiley in Ultrasound in Obstetrics & Gynecology
- Vol. 34 (1), 38-42
- https://doi.org/10.1002/uog.6422
Abstract
Objectives To assess whether early fetal growth restriction in a twin, expressed as the intertwin discrepancy in crown–rump length (CRL) between two viable twins at 7 + 0 to 9 + 6 weeks' gestation, is predictive of subsequent single fetal loss. Methods This was a retrospective analysis of data collected prospectively over 3 years. Women attending an early pregnancy unit underwent a transvaginal ultrasound examination. In women with a viable twin pregnancy between 7 + 0 and 9 + 6 weeks of gestation, the CRL ratio between the two embryos was calculated. Women were followed up and the intertwin discrepancy in CRL at the 7 + 0 to 9 + 6‐week scan was compared between cases in which there was spontaneous reduction to a singleton and those in which both twins remained viable at the 11–14‐week scan. Results There were 77 women included in the study and nine (12%) of these had a single fetal loss. Pregnancies with subsequent single fetal loss were more likely to have a larger median CRL discrepancy (42.0%; interquartile range (IQR), 23.8–64.3%) than were those which retained two viable fetuses (6.1%; IQR, 2.2–12.5%) (P < 0.0001). The median CRL discrepancy in subsequently viable monochorionic diamniotic twins (10.9%; IQR, 1.9–17.5%) was no different from that in dichorionic diamniotic twin pregnancies (5.9%; IQR, 2.1–12.3%) (P = 0.305). Regardless of chorionicity, there was a relationship between increasing CRL discrepancy and single fetal loss; the likelihood of a subsequently viable twin pregnancy was 97% if the discrepancy was < 20%, while if the discrepancy was > 60% there were no cases of both twins remaining viable (P < 0.0001). Receiver–operating characteristics curve analysis of CRL discrepancy in predicting single fetal loss gave an area under the curve of 0.93, with an optimum cut‐off point of 16.9% discrepancy (sensitivity, 88.9%; 95% CI, 51.8–99.7; and specificity, 86.7%; 95% CI, 76.3–93.8). Conclusion There is a significant relationship between CRL discrepancy at 7 + 0 to 9 + 6 weeks and the likelihood of subsequent single intrauterine fetal loss. This suggests that spontaneous fetal demise of one twin may be preceded by growth restriction in the first trimester. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.Keywords
This publication has 18 references indexed in Scilit:
- Evidence of early first-trimester growth restriction in pregnancies that subsequently end in miscarriageBJOG: An International Journal of Obstetrics and Gynaecology, 2008
- Spontaneous embryonic loss following in vitro fertilization: Incidence and effect on outcomesAmerican Journal of Obstetrics and Gynecology, 2004
- The significance of crown–rump length measurement for predicting adverse pregnancy outcome of threatened abortionUltrasound in Obstetrics & Gynecology, 2001
- The vanishing twin: a reviewHuman Reproduction Update, 1998
- Sonography of pregnancies with first‐trimester bleeding and a viable embryo: a study of prognostic indicators by logistic regression analysisUltrasound in Obstetrics & Gynecology, 1996
- Outcome of triplet pregnancies after assisted reproductive techniques: How frequent are the vanishing embryos?Fertility and Sterility, 1995
- Outcome of twin gestations following sonographic demonstration of two heart beats in the first trimesterUltrasound in Obstetrics & Gynecology, 1993
- The natural history of multiple pregnancies after assisted reproduction: is spontaneous fetal demise a clinically significant phenomenon?Fertility and Sterility, 1993
- Spontaneous fetal reduction in multiple gestations assessed by transvaginal ultrasoundBJOG: An International Journal of Obstetrics and Gynaecology, 1992
- Fetal growth delay in threatened abortion: an ultrasound studyBJOG: An International Journal of Obstetrics and Gynaecology, 1982