Original ResearchObstetricsDevelopment of customized fetal growth charts in twins
Section snippets
Study population
This was a retrospective multicentric study performed in 19 Italian units under the auspices of the Società Italiana di Ecografia Ostetrica e Ginecologica (SIEOG; www.sieog.it). All the units had proven expertise in sonographic assessment of fetal growth and were opted in by the steering committee of the study. Data were obtained from the combined ultrasound and delivery databases of each unit for pregnancies delivered between January 2010 and December 2015.
Inclusion criteria were an
Results
Complete ultrasound fetal biometric data were obtained from 1781 twin pregnancies including 1289 DC and 439 MCDA gestations that fulfilled the inclusion criteria. Overall, 8923 ultrasonographic examinations were available (6640 in DC and 2463 in MCDA). The median number of observations per twin pregnancy was 5 in DC (range, 2–8) and 6 in MCDA (range, 2–11). The characteristics of the study population are shown in Table 1. When compared with DC twins, MCDA pregnancies showed a lower incidence of
Principal findings
In a large population of uncomplicated dichorionic and monochorionic twin pregnancies, we documented a different growth pattern in comparison with singleton fetuses, with a flattening of the biometric curve starting at 26–28 weeks of gestation for all biometric parameters. Differences with singleton charts were larger in monochorionic twins, progressively increasing during the third trimester for some parameters such as AC. Moreover, as previously shown in singletons,19, 20 a relationship
Conclusion
In conclusion, this large retrospective study has confirmed that the intrauterine growth of uncomplicated twin pregnancies is reduced in comparison with singletons starting from 26–28 weeks. This reduction is more evident in monochorionic twins. The growth pattern of the fetal biometric parameters is significantly influenced by parental variables and fetal sex. The reference ranges for gestation constructed in this study may provide a useful tool for a more accurate assessment of fetal growth
Acknowledgment
The Società Italiana di Ecografia Ostetrica e Ginecologica (SIEOG) Working Group on Fetal Biometric Charts collaborating authors include the following: D. Arduini, S. Arduino, E. Aiello, S. Boito, C. Celentano, N. Chianchiano, G. Clerici, E. Cosmi, V. D’addario, C. Di Pietro, G. Ettore, E. Ferrazzi, T. Frusca, S. Gabrielli, P. Greco, I. Lauriola, G. M. Maruotti, A. Mazzocco, D. Morano, E. Pappalardo, A. Piastra, M. Rustico, T. Todros, T. Stampalija, S. Visentin, N. Volpe, P. Volpe, and C.
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2024, American Journal of Obstetrics and Gynecology MFMClinical implementation of twin-specific growth charts: still more work to do
2023, American Journal of Obstetrics and GynecologyShould twin-specific growth charts be used to assess fetal growth in twin pregnancies?
2022, American Journal of Obstetrics and GynecologyCitation Excerpt :The relatively asymmetrical growth pattern of twins compared with singletons (as described previously) may also be supportive of this argument. In contrast, some have disagreed with this explanation and argued that twins already demonstrate reduced growth early in the third trimester at a time when nutrient supply across the placenta is unlikely to be a limiting factor.41,60,61 In addition, several studies found that twins diagnosed as SGA based on singleton charts are less likely to have placental histopathological abnormalities than SGA singletons.62–64
Chorionicity, birth weight discordance and neonatal morbidity in uncomplicated twin pregnancies delivered from 36 weeks
2022, European Journal of Obstetrics and Gynecology and Reproductive BiologyManagement and outcome of twin pregnancies
2022, Twin Research for Everyone: From Biology to Health, Epigenetics, and PsychologyDevelopmental outcomes in small-for-gestational age twins using a singleton vs twin birthweight reference
2021, American Journal of Obstetrics and Gynecology MFMCitation Excerpt :Because of the differential growth trajectory of twins and singletons, and because a growth-restricted label in utero may increase the risk of iatrogenic preterm delivery and its complications,7 the overdiagnosis of twins as SGA has led researchers and clinicians to debate the necessity of twin-specific references to evaluate twin birthweight and outcomes. Limited data exist about long-term developmental differences among SGA twins, but researchers have called for the development of twin-specific references in predicting short-term outcomes, such as neonatal morbidity and mortality.8–11 Singleton-specific references may overestimate the risk of serious morbidity and mortality in twins10 and may not predict neonatal morbidity or stillbirth in twins as accurately as twin-specific references.9
The authors report no conflict of interest.
Cite this article as: Ghi T, Prefumo F, Fichera A, et al. Development of customized fetal growth charts in twins. Am J Obstet Gynecol 2017;216:514.e1-17.