Effect of Patient Age and Embryo Parameters on Pregnancy Outcomein In Vitro Fertilization-Embryo Transfer(IVF-ET)

Objective To study the effect of patient age,the number and quality of embryos transferred on pregnancy outcome in in vitro fertilization-embryo transfer procedures (IVF-ETs).Methods A retrospective study was conducted with infertile women who underwent a total of 1 800 cycles of IVF-ET and intracytoplasmic sperm injection (ICSI) at the Reproductive Medicine Center of the Third Affiliated Hospital of Guangzhou Medical College from Jan.2006 to Dec.2007.The patients were divided into three groups based on age (year):<30,30-34 and ≥ 35.The rates of clinical pregnancy and multiple pregnancies were compared in each group when 1-3 embryos and 0-3 good-quality embryos were transferred respectively.Results 1) In the group of patients aged <30 years,there was no significant difference in pregnancy outcomes with 1-3 embryos transferred.However,pregnancy rates were similar when 2-3 good-quality embryos were transferred,which was significantly higher compared with 0-1 good-quality embryos transferred;the incidence of multiple pregnancies was not an issue when only 1 embryo was transferred.2) The pregnancy rate of the patients aged 30-34 was not significant not only when only 2-3 embryos were transferred but also when 2-3 good-quality embryos were transferred,which was significant compared with when 1 embryo or 0-1 good-quality embryo was transferred.The subgroup of 3 good-quality embryos transferred,at the same time,was expected to significantly increase multiple pregnancy rate.3) For the patients aged ≥ 35,there were similar pregnancy rates in the subgroup involving 1-3 embryos transferred.Compared with 0-2 good-quality embryos transferred,the pregnancy rate was significantly higher in the patients with 3 good-quality embryos transferred.An increased trend toward multiple pregnancies was observed among not only the subgroups with 1-3 embryos transferred,but also when 1-3 good-quality embryos were transferred,although it was significantly higher in patients with 3 good-quality embryo transferred.Conclusion In an effort to achieve the ideal pregnancy rate without the risk of multiple pregnancies,it is desirable to employ a single good-quality embryo transfer for patients aged <30 years and 2 good-quality embryos for patients aged ≥ 30.As older women (aged ≥ 35 years),this is important,need to abstain from poor-quality embryo transferred by increasing the number of embryos transferred in an effort to improve the rate of clinical pregnancy,if the patients have had enough 2 high-quality embryos.