Single embryo transfer - state of the art

Area of Science:

• Reproductive Medicine
• Assisted Reproductive Technology

Background:

• Twin and higher-order multiple pregnancies pose significant risks and complications in assisted reproduction.
• Single embryo transfer (SET) is a strategy to mitigate these risks by reducing multiple gestations.

Purpose of the Study:

• To evaluate the effectiveness of elective SET in reducing twin pregnancy rates while maintaining ongoing pregnancy rates.
• To identify key patient and embryo selection criteria for successful SET.
• To review published data and health economic aspects of SET.

Main Methods:

• Analysis of SET practices and outcomes at the Centre for Reproductive Medicine, Middelheim Hospital.
• Review of published literature on SET, including patient and embryo selection criteria.
• Examination of pregnancy rates, including ongoing and multiple pregnancy rates, and the impact of frozen-thawed cycles.

Main Results:

• In 2002, 39% of transfers were SET, maintaining a 30.6% ongoing pregnancy rate.
• The twin (multiple) pregnancy rate decreased to 11.7% with SET.
• Frozen-thawed cycles showed an augmenting effect on pregnancy rates.

Conclusions:

• Elective SET, combined with careful patient and embryo selection (e.g., women <38 years, first/second IVF/ICSI cycle, high implantation potential embryo), effectively reduces twin pregnancy rates.
• SET maintains stable ongoing pregnancy rates and offers health economic benefits.
• The use of frozen-thawed cycles further enhances the success of SET programs.