Are first-trimester screening markers altered in assisted reproductive technologies pregnancies?

Area of Science:

• Prenatal Diagnosis
• Maternal-Fetal Medicine
• Reproductive Endocrinology

Background:

• First-trimester screening is crucial for detecting fetal aneuploidies like trisomy 21.
• Assisted reproductive technologies (ART) are increasingly used for conception.
• ART pregnancies may have unique characteristics affecting screening markers.

Purpose of the Study:

• To review literature on first-trimester screening in ART singleton and twin pregnancies.
• To assess the performance of sonographic and biochemical markers in ART pregnancies.
• To identify specific challenges and recommendations for ART pregnancies.

Main Methods:

• Literature review of first-trimester screening studies.
• Analysis of sonographic markers (nuchal translucency) in ART pregnancies.
• Evaluation of biochemical markers (free β-hCG, PAPP-A) in ART pregnancies.

Main Results:

• Nuchal translucency measurements show comparable results in ART singletons and twins versus spontaneous conceptions.
• ART singletons exhibit minor nuchal translucency deviations without impacting overall screening performance.
• Maternal serum markers (free β-hCG, PAPP-A) are altered in ART pregnancies, risking higher false positives without adjustments.
• Chorionicity is a confounding factor in ART twin pregnancies, impacting screening markers but insufficiently studied.

Conclusions:

• First-trimester nuchal translucency screening performs similarly in ART and spontaneous singleton/twin gestations.
• Adjustments for maternal serum biochemistry are necessary for ART pregnancies.
• Further research on ART twin pregnancies is essential for conclusive screening strategies.