Clinical Use of Combined First-Trimester Screening Test for Aneuploidy in A Low-Income Setting: Retrospective Study

Area of Science:

• Obstetrics and Gynecology
• Prenatal Diagnostics
• Medical Genetics

Background:

• Combined first trimester screening (cFTS) is crucial for detecting fetal aneuploidies like trisomy 21, 18, and 13.
• Limited data exists on cFTS implementation and effectiveness in low-income countries.
• This study addresses the gap by presenting data on cFTS in a Sub-Saharan African population.

Purpose of the Study:

• To evaluate the clinical utility and outcomes of combined first trimester screening in a low-income, Sub-Saharan African setting.
• To identify factors associated with screening-positive results for aneuploidy.

Main Methods:

• A retrospective analysis of 141 pregnant women undergoing cFTS between July 2016 and June 2023.
• Risk assessment utilized maternal age, nuchal translucency (NT), pregnancy-associated plasma protein-A (PAPP-A), and beta-human chorionic gonadotropin (β-hCG) via Snibe 2000 software.
• Statistical analysis included Fisher's exact and Mann-Whitney U tests, with P < 0.05 indicating significance.

Main Results:

• The overall high-risk rate for aneuploidy was 24.8%.
• Screening-positive results were significantly associated with increased NT (P=0.021) and low PAPP-A levels (P=0.005).
• A higher prevalence of screening-positive cases was observed, potentially due to the high-risk study population.

Conclusions:

• Combined first trimester screening is feasible and effective for identifying fetal chromosomal anomalies in low-income settings.
• Nuchal translucency and low PAPP-A are key indicators for aneuploidy screening.
• Enhancing laboratory capacity for serum analysis and ultrasound services is vital for broader access to prenatal genetic screening.