First trimester biochemical markers in twin pregnancies

Area of Science:

• Maternal-fetal medicine
• Prenatal screening
• Twin pregnancy research

Background:

• First trimester screening is crucial for assessing fetal aneuploidy risk.
• Twin pregnancies present unique physiological differences impacting screening markers.
• Understanding these differences is key to accurate risk assessment.

Purpose of the Study:

• To investigate first trimester serum markers and nuchal translucency (NT) in twin pregnancies.
• To compare these markers between twin and singleton pregnancies.
• To establish population-specific reference ranges for twin screening.

Main Methods:

• Retrospective review of double tests performed over three years.
• Comparison of 49 twin pregnancies with 147 singleton controls.
• Analysis of nuchal translucency (NT) and serum markers: PAPP-A and fβ-hCG.

Main Results:

• No significant differences in NT measurements between twins and singletons.
• Median levels of Pregnancy-Associated Plasma Protein A (PAPP-A) and fβ-hCG were significantly higher in twins.
• Assisted reproductive technologies did not significantly alter PAPP-A or fβ-hCG MoM values.

Conclusions:

• Median PAPP-A and fβ-hCG levels in twin pregnancies are elevated compared to singletons.
• NT measurements are comparable between twin and singleton pregnancies in the first trimester.
• These findings aid in refining first trimester screening protocols for twin gestations.