Microfluidic Chip Method Versus Density-gradient Centrifugation Method in IVF

Infertile patients attending IVF treatment at the Centre of Assisted Reproduction and Embryology, Queen Mary Hospital and Kwong Wah Hospital will be recruited during ovarian stimulation for IVF. Subsequently, they will be randomly assigned on the day of oocyte retrieval by a laboratory staff into one of the following two groups: (1) the microfluidic chip group and (2) the density gradient group for sperm preparation and subsequent use in fertilization. Other IVF procedures will be the same as our usual practice. Both patients and clinicians were blinded from the group allocation i.e. a double blind study. The primary outcome is the cumulative live birth rate defined as the number of pregnancies leading to live birth within 6 months of randomisation.