Fetal cardiac function at midgestation and conception by in-vitro fertilization.

Area of Science:

• Cardiology
• Reproductive Medicine
• Fetal Medicine

Background:

• In vitro fertilization (IVF) is a common method for assisted reproduction.
• Previous studies suggest potential differences in outcomes for IVF pregnancies.
• Cardiac development in fetuses conceived via IVF requires further investigation.

Purpose of the Study:

• To compare cardiac morphology and function at midgestation in fetuses conceived by IVF versus natural conception.
• To investigate if fresh or frozen embryo transfer affects fetal cardiac development.
• To assess placental perfusion and function in IVF pregnancies.

Main Methods:

• Prospective study of 5801 pregnancies (343 conceived by IVF).
• Conventional and advanced echocardiography (speckle-tracking) for fetal cardiac assessment.
• Analysis of ventricular sphericity index, global longitudinal strain, and ejection fraction.
• Measurement of uterine artery pulsatility index (UtA-PI) and placental growth factor (PlGF).

Main Results:

• IVF fetuses had lower ventricular sphericity index (more globular heart) and reduced left ventricular ejection fraction compared to naturally conceived fetuses.
• No significant cardiac differences were observed between fresh and frozen embryo transfer groups.
• IVF pregnancies showed improved placental perfusion (lower UtA-PI) and function (higher PlGF).

Conclusions:

• IVF pregnancies exhibit fetal cardiac remodeling at midgestation, characterized by altered morphology and mildly reduced systolic function.
• These cardiac changes are independent of embryo transfer method (fresh vs. frozen).
• Further research is needed to determine the long-term implications of these findings in the postnatal period.