Factors influencing pregnancy rates following in vitro fertilization and embryo transfer

An IVF fallacy: Multiple pregnancy risk is lower for older women

“…All of these factors may contribute to the decision to transfer more embryos. The number of embryos transferred seems to be the most important factor in the occurrence of multiple pregnancy (16,17), although other factors, such as the age of the female partner, the quality of embryos, the IVF indication, the number of oocytes retrieved, the cleavage rate, replacement techniques, the uterine receptivity, and the quality of the luteal phase, have also been suggested (6,16,17). Statistical analysis of the data of IVF patients has the potential for many errors, since most of the parameters are not independent.…”

“…It is known that pregnancy rates are low in older women and many authors (6,7) have reported that female age is inversely correlated with multiple pregnancy rates. It has, therefore, become the practice at many clinics to transfer more embryos in older women than in younger ones in order to improve the pregnancy rate.…”

The Role of Ultrasound in the Evaluation of Endometrial Receptivity Following Assisted Reproductive Treatments

“…Physicians may argue that UGET has additional benefits over UTT other than the diagnosis of a trial transfer inaccuracy. The evidence from studies would imply that the addition of ultrasound guidance during trial transfer would further reduce the benefit of UGET when used routinely ( Diedrich et al, 1989;Englert et al, 1986;Ghazzawi et al, 1999;Goudas et al, 1998;Hearns-Stokes et al, 2000;Leeton et al, 1982;Wood et al, 1985).…”

A Constant Room Temperature of 25°C Significantly Enhances the Efficacy of In-Vitro Fertilization

“…Although the seasonality of unassisted human conception rates and birth rates has been well documented, much less is known about the seasonality of reproductive outcome with assisted technologies, particularly in-vitro fertilization (IVF) [1]. Although several recent studies suggest the possibility of seasonal variation in the pregnancy rates after IVF, the cause of this variation has not been determined [2][3][4].…”

“…In one Australian study, the pregnancy rate was the lowest in January after the Australian Christmas/New Year vacation [2]. Stolwijk et al reported that the pregnancy rate for women who underwent oocyte aspiration was the lowest from July to September [3].…”