Abstract:

The first trimester screening test relations with the risk categories of pregnancy results Summary Purpose: The first trimester screening test is known the relationship of the increase in nucleal countability (NT), the presence of fetal anomaly and the increase in risk in the combined test with genetic diseases. However, the management of the middle-risk group, defined as 1/250-1/2000 in the combined test, is the subject of discussion. Data on the increase in NT, the presence of fetal anomalies and the pregnancy results of high and medium risk groups are required in the combined test. Based on this, the current research is aimed at achieving results for tracking and treatment by evaluating the pregnancy results of the fetus identified pathological findings in the first trimester. In the twenty-month period, the first trimester screening test and the second trimester detailed fetal examination were completed in a single perinatology unit and the result of pregnancy was documented in 268 pregnancy studies, and the presence of fetal anomaly, NT increases (3.5 mm and above) and the combined test were divided into groups as risk increases. The high risk, the combined test risk is above 1/250 and/or NT 3.5 mm, and the average risk is between 1/250-1/2000 and the combined test risk is considered to be determined. Invasive tests have achieved the fetal genetic results of pregnancies, while spontaneous or induced terminations have achieved the fetal autopsy and genetic results. The data was assessed as frequency (n) and percentage (%) . Positive predictive value (PPD) calculations were made for the first trimester scan test. Results: In 46 of the 268 single pregnancies surveyed (17%), an anomaly in the sonography (n=18,39%) or a combined test scan, a risk increase >1/2000 (n=28,61%) was found. Central nervous system anomalies were the most frequently detected anomalies (9/18, 50%). The highest rate of anöploidity (57%) was the pathology of hydrops fetalis. In 50% of the fetuses diagnosed with Trizomi 21 (2/4) the sonographic scans were normal. The combined test calculated the positive predictive value of high and medium risk at 29.4% and 12.5% respectively. As at least half of Trizomi 21 cases may not have a sonographic discovery, ultrasound and serum parameters should be treated combined. Since the combined test can detect genetic anomalies in one of every eight medium-risk fetuses, advanced diagnosis and tracking options for pregnancies in this group should be carefully planned.

Abstract:

The association between first trimester screening test risk category and pregnancy outcomes Abstract Aim: It is well known that increased fetal nuchal translucency (NT), presence of fetal anomaly, increased combined test risk is associated with genetic diseases. However, management of the so-called intermediate-risk (1/250-1/2000) group in the first trimester screening test is controversial. Data on pregnancy outcomes of increased fetal NT, presence of fetal anomaly, high- and intermediate-risk groups in the combined test are needed. Therefore, the current study aims to assess the outcomes of fetuses with risk calculation in the first trimester, providing an insight for follow-up and treatment. Materials and methods: Throughout a 20-month period, 268 pregnancies with first trimester screening test and second trimester fetal examination performed in a single perinatology unit and had subsequent documentation of pregnancy outcomes were included and grouped considering increased NT (3.5 mm and above), presence of fetal anomaly, increased combined test risk. A combined test result >1/250 risk and/or nuchal translucency (NT) ≥ 3.5 mm was considered as high-risk, whereas combined test risk between 1/250-1/2000 was denoted as intermediate-risk. Pregnancy outcomes included fetal genetic results if invasive tests were performed and fetal autopsy in cases of spontaneous or induced terminations. Data were expressed as frequency (n) and percentage (%). Positive predictive values were calculated for first trimester risk categories. Results: Forty-six out of included 268 pregnancies (17%) had any fetal anomaly on ultrasound (n=18, 39%) or increased combined test risk of >1/2000. Central nervous system defects were the most common anomalies (9/18, 50%). Fetal hydrops had the highest aneuploidy rate (57%). Sonographic screening was normal in 50% (2/4) of fetuses with trisomy 21. Positive predictive value for high- and intermediate-risk was 29.4% and 12.5%, respectively. Conclusion: Since at least half of the trisomy 21 cases may have no sonographic findings, ultrasound and serum parameters should be evaluated together. The intermediate-risk group merits special attention considering diagnostic and follow-up options, every eight fetus in this group could have an anomaly.

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