BACKGROUND The respective advantages of day 3 and day 5 embryo transfer are a matter of debate. Previous comparisons did not include pronuclear stage zygote scoring and cumulative success rates (fresh and cryopreserved embryos). METHODS Patients were randomized prospectively for day 3 or day 5 embryo transfer. Day 3 embryos were selected for transfer and cryopreservation by using combined eva...

BACKGROUND The risks of premature birth and perinatal death are increased after in vitro fertilization. These risks are mainly due to the high incidence of multiple births, which relates to the number of embryos transferred. METHODS We performed a randomized, multicenter trial to assess the equivalence of two approaches to in vitro fertilization with respect to the rates of pregnancy that res...

Background Women undergoing in vitro fertilization (IVF) cycles should successfully go through multiple points during the procedure (i.e., implantation, clinical pregnancy, no spontaneous abortion and delivery) to achieve live births. In this study, data from multiple cycles and multiple points during the IVF cycle are collected for each individual to model the effects of factors associated wit...

Background Infertility as one of most concerning topics in childbearing age mothers needs better managements with less complications and IVF can be assumed as an efficient method. This study aimed to compare pregnancy outcomes in fresh and frozen embryos transferred in IVF cycles. Methods In a retrospective study, 11201 patients underwent IVF cycles from 21st March 2013 to 20th March 2014 and...

background: the use of assisted reproductive technology (art) is increasing in the world. the rate, efficacy and safety of art are very different among countries. there is an increase in the use of intra cytoplasmic sperm injection (icsi), single fresh embryo transfer (et) and frozen-thawed embryo transfer (fet). objective: the objective of this study was to compare pregnancy rate in fresh et a...

STUDY QUESTION What type of transferred embryo is associated with a lower rate of ectopic pregnancy? SUMMARY ANSWER The lowest risk of ectopic pregnancy was associated with the transfer of blastocyst, frozen and single embryo compared with cleavage stage, fresh and multiple embryos. WHAT IS KNOWN ALREADY Ectopic pregnancy is a recognized complication following assisted reproductive technolo...

Conventionally, most in vitro fertilization (IVF) embryos are transferred in fresh treatment cycles with freezing reserved for spare ones. Improvement in cryopreservation facilities over time has encouraged the greater use of this technology with the success rate of frozen replacement cycles approaching that associated with fresh embryo transfer. Data from observational studies suggest that obs...