A comparison between multiple and single pregnancies obtained by in-vitro fertilization

Area of Science:

• Reproductive endocrinology
• In-vitro fertilization (IVF) research
• Maternal-fetal medicine

Background:

• In-vitro fertilization (IVF) allows assisted reproduction but can result in multiple pregnancies.
• Understanding the physiological differences between single and multiple IVF gestations is crucial for optimizing outcomes.
• Previous studies highlight varying success rates and risks associated with different IVF protocols.

Purpose of the Study:

• To compare physiological and developmental parameters between single and multiple pregnancies resulting from in-vitro fertilization (IVF).
• To investigate hormonal profiles and embryonic development in relation to pregnancy rank after IVF.
• To inform clinical decisions regarding embryo transfer strategies to mitigate risks of high-order multiples.

Main Methods:

• Comparative analysis of 38 single and 10 multiple pregnancies post-IVF.
• Measurement of plasma oestradiol, progesterone, and human chorionic gonadotropin (HCG) levels.
• Echographic assessment of conceptus growth and development.
• Correlation of maternal age, ovulatory drug dosage, and embryo transfer details with pregnancy outcomes.

Main Results:

• Multiple pregnancies had lower maternal age and received smaller doses of ovulatory drugs.
• Triple embryo transfers resulted in multiple gestations with higher embryo vitality scores.
• Hormonal secretion (oestradiol, progesterone, HCG) increased more rapidly in multiple pregnancies post-implantation.
• Both single and multiple IVF conceptuses showed initial growth retardation, catching up around 30 days post-retrieval.

Conclusions:

• Multiple IVF pregnancies exhibit distinct hormonal profiles and developmental trajectories compared to single gestations.
• Embryo vitality and transfer strategy significantly influence the likelihood of multiple pregnancies.
• Clinical practice should consider the risk of high-rank multiples when determining the number of embryos transferred during IVF procedures.