Martins Wellington P, Nastri Carolina O, Barra Daniela A, Navarro Paula A A S, Mauad Filho Francisco, Ferriani Rui A
Escola de Ultra-sonografia de Ribeirão Preto (EURP) e Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (FMRP-USP), Ribeirão Preto, São Paulo, Brazil.
Eur J Obstet Gynecol Reprod Biol. 2009 Jul;145(1):32-5. doi: 10.1016/j.ejogrb.2009.03.015. Epub 2009 Apr 21.
OBJECTIVE(S): We intend to verify if fetal volume and crown-rump length were different between singletons and twins in pregnancies aged from 7 to 10 weeks and to evaluate if fetal volume is more accurate to determine the gestational age than crown-rump length at this gestational age.
From 52 days (7 weeks and 3 days) to 73 days (10 weeks and 3 days) weekly three-dimensional ultrasonography was performed in 20 twin fetuses and 20 singletons. Crown-rump length and fetal volume using VOCAL were assessed in all examinations. The 'true' gestational age was based on oocyte retrieval.
At the age of 52 days, the crown-rump length was 11.74+/-0.27 mm (mean+/-S.D.) and 11.48+/-0.22 mm (singletons and twins, respectively), while the fetal volume was 0.354+/-0.015 cm(3) and 0.324+/-0.012 cm(3). At the gestational age of 73 days, the crown-rump length was 36.19+/-0.90 mm and 35.87+/-0.54 mm and the fetal volume was 6.204+/-0.090 cm(3) and 6.083+/-0.081 cm(3). The total relative increase observed was much higher for fetal volume than for CRL: 1705+/-301% vs. 210+/-33% in singletons and 1827+/-305% vs. 214+/-25% in twins. The 95% limits of agreement (+/-2.3 days vs.+/-3.2 days, fetal volume vs. crown-rump length) and the intraclass correlation coefficients (0.989 vs. 0.978) between the "true" gestational age and that predicted by fetal volume were better than those predicted by crown-rump length. No significant difference was identified between singletons and twins for both fetal volume and crown-rump length.
CONCLUSION(S): Twins and singletons had similar fetal volume and crown-rump length between the 7th and 10th week of gestational age. Additionally, fetal volume assessed by VOCAL was better than crown-rump length to estimate the gestational age at the evaluated period. However, the improvement was small and probably without clinical significance.
Fetal volume and crown-rump length were similar between singletons and twins. Fetal volume relative increase was higher and the predicted gestational age was better.
我们旨在验证7至10周妊娠的单胎和双胎胎儿的体积及头臀长是否存在差异，并评估在此孕周时胎儿体积在确定胎龄方面是否比头臀长更准确。
对20例双胎胎儿和20例单胎胎儿从52天（7周零3天）至73天（10周零3天）每周进行一次三维超声检查。在所有检查中评估使用VOCAL技术测量的头臀长和胎儿体积。“真实”胎龄基于取卵时间。
在52天时，单胎和双胎的头臀长分别为11.74±0.27毫米和11.48±0.22毫米，而胎儿体积分别为0.354±0.015立方厘米和0.324±0.012立方厘米。在73天孕周时，头臀长分别为36.19±0.90毫米和35.87±0.54毫米，胎儿体积分别为6.204±0.090立方厘米和6.083±0.081立方厘米。观察到的胎儿体积的总相对增加远高于头臀长：单胎中分别为1705±301%和210±33%，双胎中分别为1827±305%和214±25%。“真实”胎龄与胎儿体积预测胎龄之间的95%一致性界限（胎儿体积为±2.3天，头臀长为±3.2天）和组内相关系数（分别为0.989和0.978）优于头臀长预测的结果。单胎和双胎在胎儿体积和头臀长方面均未发现显著差异。
在孕7至10周时，双胎和单胎的胎儿体积及头臀长相似。此外，在评估期间，用VOCAL技术评估的胎儿体积在估计胎龄方面优于头臀长。然而，这种改善很小，可能无临床意义。
单胎和双胎的胎儿体积及头臀长相似。胎儿体积相对增加更高，预测胎龄更准确。
