Revista Brasileira de Ginecologia e Obstetrícia (Jan 1999)
Teste triplo biofísico: um novo parâmetro ultra-sonográfico para prognóstico em gestações iniciais Biophysical triple test: a new ultrasonographic parameter for prognostic evaluation in early pregnancies
Abstract
Objetivos: atrasos no desenvolvimento do saco gestacional (SG), no tamanho do botão embrionário (CCN), assim como freqüências cardíacas embrionárias (FCE) baixas podem ser considerados fatores de mau prognóstico na evolução da gestação. O objetivo deste trabalho foi avaliar a utilização destes 3 parâmetros em conjunto, o que denominamos Teste Triplo Biofísico (TTB). Metodo: foram avaliadas 35 gestações únicas provenientes de fertilização assistida por injeção intracitoplasmática de espermatozóide (ICSI). Todos os exames de ultra-som foram realizados por um único examinador, após 4-5 semanas da transferência de embriões (6-7 semanas de gestação), com equipamento modelo Synergy da Diasonics, sonda transvaginal de 7,0 MHz. O SG foi medido em seu maior diâmetro transverso, o CCN foi medido no sentido sagital e a FCE pelo modo B-M e Doppler. Na análise estatística foi utilizado o teste de Fisher. Resultados: considerou-se como parâmetros alterados : SG Purpose: it has been demonstrated that delays in gestational sac development, in crown-rump length and low embryonic heart rate could be indicators of poor pregnancy outcome. The purpose was to evaluate the use of these three parameters together, which we named Biophysical Triple Test (BTT). Method: thirty-five singleton pregnancies following IVF treatment with intracytoplasmatic sperm injection (ICSI) were studied. All ultrasonographic scans were performed by the same examiner, 4-5 weeks after embryo transference (6-7 week gestation), using a Diasonics equipment, model Synergy, with a 7.0-MHz transvaginal transducer. The gestational sac (GS) was measured at the longest transverse diameter; the crown-rump length (CRL) was measured at the sagittal plan and the embryonic heart rate (EHR) was calculated from frozen B and M-mode and Doppler. The statistical test used was Fisher's test. Results: the following parameters were considered abnormal: GS < 15.4 mm, CRL < 3.9 mm, EHR < 100 bpm. The parameters were calculated from the means less one standard deviation for the ongoing pregnancies. The patients with a positive BTT, i.e., with a high risk of miscarriage, were those with at least 2 altered parameters. In 35 pregnancies, a positive BTT was found in 5, all of those who miscarrided and 2 of those who had no miscarriage. The difference between the two groups was highly significant (p = 0.0015; t-Fisher). The sensitivity of the method was is 100%, with a specificity of 93.75 %, which resulted in a 96.87% efficacy. Conclusion: the BTT is an ultrasonographic noninvasive method that presents high efficacy as an indicator of poor pregnancy outcome.
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