Introduction:
It has been over 40 years since the development of assisted reproductive
technology. With the improvements of assisted reproductive technologies
such as ovulation induction, embryo culture and vitrification, and other
technologies, experts in the field of reproductive medicine are no
longer only concerned about pregnancy rates, but of delivering healthy
live births. At present, the most common clinical transfer strategies
include twin embryo and single blastocyst transfer. In addition, single
embryo and double blastocyst transfer will also be performed in the
clinic under certain conditions. How to choose a way that can ensure the
success rate of transplantation and reduce the incidence of
complications to the greatest extent is the focus of clinicians.
Different transplantation methods may have different outcomes in
different countries and
races1,
2. In order to study the advantages and
disadvantages of these four transplantation methods, we selected two
large reproductive medical centers, one in Beijing and the other in
Shenzhen, to represent the northern and southern regions of China
respectively. The majority of individuals in China belong to the
Mongoloid race. This study aims to provide an evidence-based assessment
of the benefits and harms of four transplantation methods so as to
improve the superior pregnancy outcome and reduce the pregnancy rate of
multiple embryos in the Mongoloid race.