Microfluidics Versus Gradient Centrifugation Effect on Euploidy Rates

As part of the in vitro fertilization (IVF) process, eggs are removed from the ovaries and are inseminated (mixed) or injected with sperm. In order for fertilization to occur, the sperm cells must be separated from the semen before introducing them to the eggs. Currently, sperm are isolated from the semen using a series of wash steps in a centrifuge (device to spin and concentrate the sperm). This requires processing at high speeds in order to separate motile sperm from the other parts of the semen. Although it is common practice, it is possible that this method of processing the semen may cause damage to the sperm cells.

Alternatively, a microfluidics chamber can be used to choose the best sperm. A microfluidics chamber is a small device in which the unwashed sperm can be placed at one end. Sperm that are moving forward will swim through the chamber and come out the other end. Dead sperm are left behind and the sperm with the best motility (how normally they move forward) and normal morphology (how the sperm looks) will make it to the other end of the chamber. These sperm can then be chosen for injection into the egg. This device is FDA-approved for this purpose and is commercially available and is currently routinely used in the IVF lab utilized by the investigators as well as most labs in the country.

Some small initial studies showed that a higher number of embryos with higher quality were made with sperm selected from a microfluidics chamber. In another recent study, the chances of creating an embryo with a normal number of chromosomes (structures that carry genetic information) was also slightly higher if a microfluidics chamber was used to process the sperm. This might be because sperm that have the highest motility and normal morphology may also be more likely to be genetically normal. However, there are no good-quality studies looking at the rates of embryos with normal chromosomes created from using a microfluidics chamber to process sperm.

The purpose of this research study is to determine whether using a microfluidics chamber to process sperm for injection into eggs increases the rates of embryos with normal chromosomes. At the time of egg retrieval, participants will have their eggs randomized (like the flip of a coin) into two groups. Half of the eggs will be injected with sperm processed using gradient centrifugation, the standard method. The other half of the eggs will be injected with sperm processed using a microfluidics chamber. The goal is to determine the rate of embryos with normal chromosomes in each group. Other goals include looking at how many embryos develop to good quality blastocysts and are biopsied and how many patients get pregnant after embryo transfer.

Inclusion criteria

• Subjects are nonpregnant females ≥ 18 years and ≤ 42 years of age.
• Subjects obtain ≥ 6 mature oocytes at the time of oocyte retrieval or at the time of ICSI.
• Subjects are utilizing ICSI for fertilization.
• Subjects are utilizing PGT-A (PGT for aneuploidy).
• Subjects are able to understand, read, and write in English at a fifth-grade level.
• Subjects are willing to comply with study protocol and procedures and provide written informed consent.

Exclusion criteria

• Subjects are utilizing donor oocytes, donor sperm, or gestational carrier.
• Subjects have a diagnosis of severe male factor infertility (sperm concentration < 5 mil/mL at semen analysis).
• Subjects are utilizing surgically removed sperm (e.g. via testicular sperm aspiration [TESA] or microsurgical epididymal sperm aspiration [MESA]).
• Subjects are utilizing frozen/thawed sperm.
• Subjects are utilizing frozen/thawed oocytes.
• Subjects are undergoing a day 3 (cleavage stage) embryo transfer.
• Subjects obtain < 6 mature oocytes at the time of oocyte retrieval or at the time of ICSI.
• Subjects obtain ≥ 6 mature oocytes but choose to fertilize fewer than 6 of them.
• Sperm sample parameters are low on the day of oocyte retrieval (semen volume < 1.0 mL or concentration < 1 million motile/mL).
• Male partner has an infectious disease.