Sir, We read with great interest the study entitled ‘Transfer of fresh or frozen embryos: a randomized controlled trial’ (Wong et al., 2021), recently accepted for publication in Human Reproduction. In this well-designed (n = 204), Wong al. tried to address question whether elective ‘embryo freeze-all strategy’ (i.e. transfer frozen-thawed blastocysts [FETs]) was superior ‘conventional and FETs...

OBJECTIVE The aim of this prospective study was to investigate whether ovarian blood flow is related to embryological parameters and whether it could be a predictor of outcomes of IVF/ICSI. METHODS Eighty infertile women underwent ovarian stimulation with gonadotrophins after a long protocol with GnRH agonists. The ovarian volume (OV), number of follicles (NF) and follicular volume (FV) of al...

BACKGROUND The main reason for adverse treatment outcome in assisted reproduction is the high rate of multiple pregnancies. The only strategy to avoid dizygotic twins is to transfer one embryo at a time. METHODS A total of 144 women, who had had at least four good quality embryos available after IVF/intracytoplasmic sperm injection (ICSI) and who had no more than one previous failed treatment...

Here we assess bisphenol A (BPA) in couples undergoing in vitro fertilization (IVF) and indicators of embryo quality; embryo cell number (ECN) and embryo fragmentation score (EFS). Twenty-seven couples provided serum on the day of oocyte retrieval. Unconjugated BPA was measured by HPLC with Coularray detection. Odds ratios (OR) were generated using ordinal logistic regression including female a...

UNLABELLED OBJECTIVES This study sought to evaluate the outcome of fresh and vitrified-warmed cleavage-stage and blastocyst-stage embryo transfers in patients undergoing ART treatment within an ethnic Chinese population. STUDY DESIGN We compared the clinical results of embryo transfer on the 3rd (cleavage stage) or 5th (blastocyst stage) day after oocyte retrieval, including clinical pregn...

INTRODUCTION In several clinics, elective single-embryo transfer (eSET) is applied in a selected group of patients based on age and the availability of a good-quality embryo. Whether or not eSET can be applied irrespective of the presence of a good-quality embryo in the first cycle, to further reduce the twin pregnancy rate, remains to be elucidated. METHODS In patients <38 years two transfer...