Autologous mitochondrial transfer as a complementary technique to intracytoplasmic sperm injection to improve embryo quality in patients undergoing in vitro fertilization-a randomized pilot study

Abstract

Objective: To study if autologous mitochondrial transfer (AUGMENT) improves outcome in patients with previously failed in vitro fertilization (IVF).

Design: Randomized, controlled, triple-blind, experimental study.

Setting: Private infertility center, Valencian Institute of Infertility (IVI-RMA), Valencia, Spain.

Patient(s): Infertile women ≤42 years of age, body mass index <30 kg/m², antimüllerian hormone ≥4 pmol/L, >5 million/mL motile sperm, at least one previous IVF with at least five metaphase oocytes (MIIs) collected, and low embryo quality.

Interventions(s): An ovarian cortex biopsy was performed to isolate egg precursor cells to obtain their mitochondria. Sibling MIIs were randomly allocated to AUGMENT (experimental) or intracytoplasmic sperm injection (Control). In AUGMENT, mitochondrial suspension was injected along with the sperm. Viable blastocysts from both groups were biopsied for preimplantation genetic testing for aneuploidy.

Main outcome measure(s): Pregnancy, embryo quality.

Result(s): An interim analysis was conducted. The patients' mean age was 36.3 ± 3.6 years, and they had an average of 2.5 ± 1.5 previous IVF cycles. Two of the 59 enrolled patients spontaneously conceived (one miscarried). Fifty-seven patients had ovarian biopsies and underwent stimulation. Oocyte retrieval was performed in 56 patients (premature ovulation; n = 1). A total of 253 MIIs were inseminated in AUGMENT and 250 in Control; fertilization rates were 62.7 ± 30.0% and 68.7 ± 29.1%, respectively. Statistical differences were observed in day 5 blastocyst formation rates (23.3 ± 32.0% vs. 41.1 ± 36.9%). Neither the euploid rate per biopsied blastocyst (43.8 ± 41.7% vs. 63.8 ± 44.1%) nor the euploid rate per MII (9.8 ± 20.5% vs. 11.9 ± 16.1%) between AUGMENT and Control achieved statistical significance. Moreover, no differences were seen regarding mitochondrial DNA content and relevant morphokinetic variables. Thirty patients were able to undergo embryo transfer. Cumulative live birth rates per transferred embryo were 41.6% in AUGMENT and 41.2% in Control.

Conclusion(s): AUGMENT does not seem to improve prognosis in this population. Therefore, the study has been discontinued.

Clinical trial registration number: NCT02586298.

Keywords: Autologous germline mitochondrial energy transfer (AUGMENT); IVF failures; egg precursor cells (EggPCs); euploidy; poor embryo quality.