Nearly half of all severe fetal anomalies can be detected by first-trimester screening in experts’ hands

Abstract

Objective To evaluate the detection rate of severe fetal anomalies at the first-trimester screening (FTS) and, vice versa, to evaluate the follow-up of pathological results at FTS at the time of mid-trimester screening (MTS) and throughout pregnancy and delivery in a partially selected population of low-risk pregnancies. Methods We conducted a prospective study on the detection of severe fetal anomalies at routine FTS in 9891 pregnant women with 10,294 fetuses between 11 + 0 and 13 + 6 weeks of gestation. The findings of FTS were compared to the results of MTS and pregnancy and neonatal outcomes. Only cases with severe fetal anomalies were taken for statistical analysis in this study. Results There were 232 cases of fetal anomaly altogether. At the time of FTS, sonographic anomalies were diagnosed in 113 cases and further ultrasound controls arranged. In four cases, fetal anomaly was not confirmed by MTS; in the remaining 109 cases, the sonographic anomaly seen at FTS was confirmed at MTS and in the course of pregnancy with a resulting sensitivity for fetal malformation at FTS of 47.8%, a specificity of 99.96%, a positive predictive value of 96.5% and a negative predictive value of 98.8%. Conclusion FTS can detect almost half of all severe fetal anomalies at an early stage of pregnancy with positive predictive values of 90% and more. Sensitivities varied depending on the organ system and reached the highest figures for anomalies of the heart, the abdomen, the spine and the skeletal system.

Commentary: Implications of SARS-Cov-2 infection for pregnancy with diabetes: achievements and open questions for feto-maternal medicine

“…Leaving out advanced fetal sonography even at early gestation (e.g. due to limited health care access during the COVID-19 pandemic) can potentially cause severe complications in later pregnancy – for example due malformations which could be otherwise detected already at the first trimester [ 13 ]. Research on the complex interaction between SARS-Cov-2 infection, diabetes and pregnancy is still ongoing and it will take years even after the end of the global COVID-19 pandemic to capture all aspects and consequences of the current health care crisis for feto-maternal medicine.…”

AIUM Practice Parameter for the Performance of Detailed Diagnostic Obstetric Ultrasound Examinations Between 12 Weeks 0 Days and 13 Weeks 6 Days

“…Many anomalies that were historically diagnosed in the second trimester can be identified in the latter part of the first trimester by sonographers and sonologists. [7][8][9][10][11][12][13][14][15][16][17] The components of this examination promote a systematic method of assessing fetal anatomy that optimizes the detection of anomalies. [17][18][19][20][21][22] Approximately 50% of major anomalies are detectable in singletons and 25% in twins in this gestational age window, although there is significant variability among organ systems.…”

“…[7][8][9][10][11][12][13][14][15][16][17] The components of this examination promote a systematic method of assessing fetal anatomy that optimizes the detection of anomalies. [17][18][19][20][21][22] Approximately 50% of major anomalies are detectable in singletons and 25% in twins in this gestational age window, although there is significant variability among organ systems. 13,14,[17][18][19][20][21][22][23][24][25] Some malformations, such as anencephaly, alobar holoprosencephaly, ectopia cordis, body stalk abnormalities, and large abdominal wall defects, are usually identified.…”

“…[17][18][19][20][21][22] Approximately 50% of major anomalies are detectable in singletons and 25% in twins in this gestational age window, although there is significant variability among organ systems. 13,14,[17][18][19][20][21][22][23][24][25] Some malformations, such as anencephaly, alobar holoprosencephaly, ectopia cordis, body stalk abnormalities, and large abdominal wall defects, are usually identified. 14,16,17,[19][20][21][22][23]25 Certain anomalies such as microcephaly and callosal agenesis are not sonographically detectable during this period.…”

“…13,14,[17][18][19][20][21][22][23][24][25] Some malformations, such as anencephaly, alobar holoprosencephaly, ectopia cordis, body stalk abnormalities, and large abdominal wall defects, are usually identified. 14,16,17,[19][20][21][22][23]25 Certain anomalies such as microcephaly and callosal agenesis are not sonographically detectable during this period. Anomaly detection rates increase with fetal size and may be enhanced by the use of transvaginal sonography, especially when the fetal anatomy is suboptimally visualized by the transabdominal approach.…”