background: the purpose of the study was to compare clinical pregnancy and delivery rates with fresh and frozen embryo transfer in patients admitted to shiraz- human assisted reproductive center with ovarian hyperstimulation syndrome (ohss). methods: ohss patients randomly divided in two groups, group a (n=50) with fresh embryo transfer and group b (n=50) with frozen embryo transfer. we used vi...

On a worldwide basis, more than 750,000 embryos are produced annually from superovulated donors and more than 450,000 embryos are produced using in vitro techniques. Superovulation and embryo collection are done as frequently as every 30 days. Cryopreservation and direct transfer of frozen-thawed embryos results in pregnancy rates near that of fresh embryos. Since the zona pellucida-intact in v...

Continuous improvements to assisted reproductive technology (ART) have facilitated the advancement and preservation of animal genetics as well as animal reproductive efficiency. One of the ART techniques is cryopreservation which facilitates embryo transfer procedures. In the present experiment embryos produced in vivo or in vitro were transferred to the recipient ewes just after collection (fr...

Background: In vitro fertilization (IVF) has become increasingly common, today representing about 3% of all live births in some countries. Most patients have to undergo more than one treatment in order to achieve a live birth. Thus cumulative live birth rates are highly interesting to the patients. The most important health problem in IVF is the high rate of multiple births, leading to increase...

background: sildenafil citrate may increase endometrial thickness and affect the outcome of frozen-thawed embryo transfer cycles. objective: the aim of this study was to estimate the effect of sildenafil citrate on ultrasonographic endometrial thickness and pattern and to investigate the estrogen level on the day of progesterone administration, the implantation rate and chemical pregnancy rate ...

Background: The aim of our study was to compare the resulting from transfer of embryos that cryopereserved in cleavage stage after thawing and transfer of embryos after thawing and culture in sequentional media until blastocyst formation. Materials and Methods: In this prospective clinical study, we have evaluated 128 cycles in women undergone in vitro fertilization (IVF) or intracytoplasmic sp...

BACKGROUND The availability of an efficient cryopreservation program is especially important in the case of embryos that have undergone blastomere biopsy for PGD. Unfortunately, the freezing/thawing of biopsied embryos has given disappointing results when performed at the cleavage stage. In this study, embryos diagnosed as normal after PGD were grown to the blastocyst stage, frozen and thawed f...

BACKGROUND The clinical results of in vitro fertilization of slowly frozen-thawed oocytes are known to be significantly worse than those obtained by fresh oocytes. Little is known about the factors affecting the clinical outcome of frozen-thawed oocytes. The aim of this retrospective study was to explore the role of oocyte cryopreservation in the group of patients with no available sperm on the...