P01.03: The course of the pregnancy after “normal” first-trimester-screening

Abstract

The diagnosis of severe malformations in combination with the first trimester screening (FTS) is often described in the last years. Because of the increased experience of the examiners sometimes there is the question for the necessity of the second trimester screening. This led us to analyse the course of the pregnancy after an uneventful FTS. Inclusion criteria for the study was a “normal” FTS (nuchal translucency in the normal range, adjusted risk > 1 : 300, no malformation). There must be a second ultrasound examination in the second trimester. The examinations were done by two examiners with level III experience. Between September 01 2004 and September 31 2008 there were 4916 fetuses who fulfil the inclusion criteria. The examinations were performed with Voluson 730 expert or Voluson E8 from GE Kretztechnik. In 466 cases we are detect findings in the second trimester. We differentiate between true malformations and functional findings. The first group we found in 182 cases (heart N = 57, urogenital tract N = 54, head and brain N = 20, spine N = 3, thorax N = 2, abdomen N = 7, face N = 4, skeleton N = 5, club feed N = 8 and others). Functional findings were diagnosed in 335 cases (intrauterine growth retardation N = 63, impaired trophoblast invasion—uterine PI > 1,45 or Notch N = 222, Placenta praevia totalis/Vasa pravia/Insertio velamentosa N = 28, polyhydramnion N = 63 or anemia because of rhesus incompatibility N = 2). We found in nearly 10% of the pregnancies after uneventful FTS a suspicious finding in the second trimester. Because of various limitations we are not able to detect all severe malformations. The study supports the recommendation for the second trimester screening examination after the FTS.