Microfluidic Chip Method Versus Density-gradient Centrifugation Method in IVF

The trial will compare the use of a microfluidic chip with the use of density gradient centrifugation for sperm preparation.

The hypothesis of the study is that the use of the microfluidic chip will improve the cumulative live birth rate of IVF compared to the density gradient method.

The trial will be conducted at the Centre of Assisted Reproduction and Embryology at Queen Mary Hospital and Kwong Wah Hospital. Infertile patients undergoing IVF treatment will be recruited during ovarian stimulation. They will be randomly assigned to one of two groups: the microfluidic chip group or the density gradient group. Both the patients and the clinicians will be blinded to the group allocation.

The inclusion criteria for the study are infertile women aged under 43 years undergoing ovarian stimulation for IVF. The exclusion criteria include women undergoing certain genetic testing, male factor infertility requiring surgical sperm retrieval, the use of donor oocytes and spermatozoa, certain uterine conditions, previous participation in the study, and participation in other randomized trials.

The eligible women will undergo standard IVF procedures, including ovarian stimulation, monitoring of follicle growth, trigger for oocyte retrieval, and oocyte retrieval itself. On the day of oocyte retrieval, the women will be randomly assigned to either the microfluidic chip group or the density gradient group for sperm preparation.

Semen samples will be collected on the day of oocyte retrieval and evaluated according to standard guidelines. Sperm DNA damage will also be assessed using an alkaline single-cell gel electrophoresis assay. Depending on the randomization, the sperm samples will be prepared either using the microfluidic chip or the density gradient centrifugation method.

After sperm preparation, oocytes will be fertilized using either conventional insemination or intracytoplasmic sperm injection. Fertilization will be confirmed by the presence of two pronuclei. Fresh embryo transfer will be performed 2-5 days after egg retrieval, and luteal phase support will be given. Excessive good quality embryos or blastocysts will be cryopreserved for future use.

For frozen embryo transfer, embryos or blastocysts will be replaced in subsequent natural or hormonal replacement cycles. Pregnancy will be confirmed by a urine pregnancy test, and transvaginal ultrasound will be performed to confirm viability and the number of fetuses.

Follow-up will be conducted to retrieve pregnancy and delivery data. The cumulative live birth rate will be calculated, and pregnancy outcomes, including birth weights and obstetric complications, will be recorded and compared between the two groups.

The study will continue until all cryopreserved embryos or blastocysts are used or until the participants become pregnant within 6 months after randomization. The pregnancy complications and congenital abnormalities will be monitored through hospital records or patient contact.

Ultimately, the study aims to determine whether the use of the microfluidic chip improves the cumulative live birth rate of IVF compared to the density gradient method.

Inclusion criteria

• Infertile women aged <43 years at the time of ovarian stimulation for IVF

Exclusion criteria

• Women undergoing preimplantation genetic testing monogenic diseases, structural rearrangement of chromosomes or aneuploidy;
• Male factor requiring surgical sperm retrieval such as microscopic epididymal sperm aspiration and testicular sperm extraction;
• Use of donor oocytes and spermatozoa;
• Submucosal fibroid or hydrosalpinx shown on pelvic scanning and not surgically treated;
• Women who had been recruited into this study before and
• Women joining other randomized trials