Genetic Screening and Assisted Oocyte Activation in Couples with Diminished/aberrant Embryonic Development.

Assisted Oocyte Activation (ICSI-AOA) will be the treatment for these patients to overcome their previous embryo developmental problems. This protocol artificially induces calcium rises in the oocyte, which mimics the natural oocyte activation process induced by the sperm factor PLCzeta. If 6 or more mature oocytes are collected at oocyte retrieval, 50%ICSI and 50% ICSI-AOA will be applied to all oocytes. The best embryo(s) will be transferred back. Rest embryo(s) will be vitrified for future cycles. Patients will be followed up.

Furthermore, an additional sperm sample will be produced to investigate the calcium inducing pattern of the patients' spermatozoa. Thereby, mouse and/or human (research-donated control oocytes) will be pre-incubated with a Ca2+ sensitive dye. Next, human spermatozoa will be injected into these mouse/human oocytes and the calcium pattern will be recorded under an inverted epifluorescence microscope.

Both partners will give a saliva sample to screen for mutations possible genes involved in oocyte activation and embryo development.

Inclusion criteria

• patients with one or more previous ICSI cycles (UZ Gent) AND
• patients with:
• complete developmental arrest (no transfer), or
• complete developmental delay (no morula/blastocyst on Day 5), or
• significantly reduced blastocyst formation (≤15%)
• willing and able to give informed consent

Exclusion criteria

• patients which went for oocyte or sperm donation
• patients with severe male infertility or low fertilization (<33%) after ICSI
• cycles requiring surgical sperm recovery procedures