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High Frequency Ultrasound for the Analysis of Fetal and Placental Development In Vivo
Published on: November 8, 2018
First trimester combined screening for preeclampsia and small for gestational age - a single centre experience and
Beatrice Mosimann1, Chantal Pfiffner2, Sofia Amylidi-Mohr1
1Department of Obstetrics and Gynaecology, University Hospital, University of Bern, Switzerland.
Insights
This study validated a first-trimester screening for preeclampsia (PE), finding it effective. However, screening for small for gestational age (SGA) infants resulted in a high false positive rate.
Area of Science:
- Obstetrics and Gynecology
- Maternal-Fetal Medicine
- Cardiovascular Disease Risk Factors
Background:
- Preeclampsia (PE) poses significant maternal and fetal risks and is linked to future cardiovascular disease.
- Effective preventive strategies are crucial for managing PE and its long-term consequences.
- The Fetal Medicine Foundation developed a first-trimester screening algorithm for early-onset PE (eoPE) and preterm small for gestational age (pSGA).
Purpose of the Study:
- To externally validate the Fetal Medicine Foundation's first-trimester screening algorithm for PE and pSGA in a new population.
- To assess the performance of the screening algorithm for early-onset PE (eoPE) and preterm small for gestational age (pSGA).
Main Methods:
- A prospective study included 1129 women with singleton pregnancies undergoing first-trimester screening between September 2013 and April 2016.
- The FMF screening algorithm, utilizing maternal history, biophysical, and biochemical parameters, was applied with proposed cut-offs for eoPE (≥1:200) and pSGA (≥1:150).
- Risk calculations were performed using the Viewpoint® program, with statistical analysis conducted using GraphPad version 5.0.
Main Results:
- Nineteen women (1.68%) developed PE, with 5 (0.44%) being preterm PE (pPE) and 2 (0.18%) early-onset PE (eoPE).
- The screening algorithm demonstrated good performance for eoPE, with 97/1129 (8.6%) screening positive, including both eoPE cases.
- Screening for pSGA yielded a high false positive rate, with 210/1110 (18.9%) non-PE pregnancies screening positive, including 66.7% of pSGA deliveries.
Conclusions:
- The first-trimester screening algorithm for preeclampsia performs well in the studied population.
- Screening for preterm small for gestational age (pSGA) using this algorithm is associated with a high false positive rate.
- Further refinement of screening strategies for pSGA is warranted to improve clinical utility.
Aim Of The Study:
Preeclampsia (PE) is associated with severe maternal and fetal morbidity in the acute presentation and there is increasing evidence that it is also an important risk factor for cardiovascular disease later in life. Therefore, preventive strategies are of utmost importance. The Fetal Medicine Foundation (FMF) London recently developed a first trimester screening algorithm for placenta-related pregnancy complications, in particular early onset preeclampsia (eoPE) requiring delivery before 34 weeks, and preterm small for gestational age (pSGA), with a birth weight <5th percentile and delivery before 37 weeks of gestation, based on maternal history and characteristics, and biochemical and biophysical parameters. The aim of this study was to test the performance of this algorithm in our setting and to perform an external validation of the screening algorithm.
Material And Methods:
Between September 2013 and April 2016, all consecutive women with singleton pregnancies who agreed to this screening were included in the study. The proposed cut-offs of ≥1:200 for eoPE, and ≥1:150 for pSGA were applied. Risk calculations were performed with Viewpoint® program (GE, Mountainview, CA, USA) and statistical analysis with GraphPad version 5.0 for Windows.
Results:
1372 women agreed to PE screening; the 1129 with complete data and a live birth were included in this study. Nineteen (1.68%) developed PE: 14 (1.24%) at term (tPE) and 5 (0.44%) preterm (pPE, <37 weeks), including 2 (0.18%) with eoPE. Overall, 97/1129 (8.6%) screened positive for eoPE, including both pregnancies that resulted in eoPE and 4/5 (80%) that resulted in pPE. Forty-nine of 1110 (4.41%) pregnancies without PE resulted in SGA, 3 (0.27%) of them in pSGA. A total of 210/1110 (18.9%) non-PE pregnancies screened positive for pSGA, including 2/3 (66.7%) of the pSGA deliveries and 18/46 (39.1%) of term SGA infants.
Conclusion:
Our results show that first trimester PE screening in our population performs well and according to expectations, whereas screening for SGA is associated with a high false positive rate.
