Energizing eggs with a patient's own mitochondria offers no benefit in assisted reproduction

July 3, 2018, European Society of Human Reproduction and Embryology

A controversial technique of energising eggs to improve their quality in assisted reproduction has been shown in an experimental randomised trial to offer no benefit in terms of pregnancy or live birth rate. The study was performed at a large centre in Spain in 59 infertile patients aged 42 or less with a past record of unsuccessful IVF and now having embryo screening in a subsequent attempt; the patients were described as "difficult to treat", and thus representing those previously proposed as likely to benefit from the enhanced egg quality procedure.

The technique, which has attracted much (albeit controversial) publicity in the past few years, requires the micro-injection of isolated mitochondria resident in "egg precursor cells" (found in ovarian tissue) into the egg of the infertile patient with a partner sperm during the ICSI procedure. The technology, now a proprietary process since 2014, has been claimed in previous reports to improve egg and embryo quality and increase the success rate of ICSI.

Results of the study are presented today by Dr. Elena Labarta of the IVI clinic in Valencia, Spain, at the 34th Annual Meeting of ESHRE in Barcelona. The study was performed at the IVI clinic in Valencia, now one of the world's largest fertility centres.

The study followed the protocol suggested in the proprietary procedure. A biopsy of ovarian tissue was performed in each patient to isolate any egg precursor cells to obtain their mitochondria. Sibling eggs retrieved after stimulation in each patient were then randomised to two groups: one to receive the egg precursor cell mitochondria during ICSI, and the other to act as a control with ICSI alone. Following ICSI and fertilisation, the eggs were cultured to the blastocyst stage, when a biopsy was performed for embryo screening before transfer. Almost half the full patient group did not reach this point, mainly because of development failure during culture (and mainly in the treatment group).

Results showed that live birth rate per blastocyst transfer was 41% in the mitochondria transfer group and 39% in the control group, an indication that any "energising" effect of the mitochondria made no difference to outcome. It was also found that the number of chromosomally normal (euploid) blastocysts in the mitochondria groups was significantly less than in the control group. Labarta said that IVI has now abandoned the procedure as a study subject.

The science behind the procedure has been dogged by controversy since first reported in mice more than a decade ago. Later, in 2012, the US biologist Jonathan Tilly described the discovery of human egg-producing stem cells, dubbed "bona fide" egg precursor cells, harvested from the ovaries of six young women, which the investigators were confident would go on to make "baby-making eggs". The controversy, of course, was implicit in the biology—that eggs could now be grown from egg precursor stem cells and need not be drawn only from a fixed store which declines to zero at the menopause.

At the level of fertility treatment the belief was that these egg precursor stem cells would invigorate eggs with a patient's own mitochondria. As the proprietary website says: the "treatment uses the energy-producing mitochondria from your own egg precursor . . . cells, which are immature egg cells found in the protective lining of your ovaries, to supplement the existing mitochondria in your eggs. This process is designed to boost your eggs' energy levels for embryo development."

Results of this randomised trial now suggest that this does not happen, with no differences found in live birth rates in either of the two embryo cohorts.

Labarta described the procedure as "an invasive technique" proposed for with a poor prognosis for success in ICSI. "Unfortunately," she said, "the technique was not found useful for this type of patient, so we see no value for this patient population."

On previous studies which did show a benefit she explained that they did not include a well defined control group. "Our study, however, was the first prospective trial with an intra-patient comparison which could evaluate the net impact of the technique in the quality of the , as they all came from the same cohort," said Labarta.

So do egg precursor cells really exist? Did the IVI trial identify and isolate mitochondria from these ovarian stem cells? Unfortunately, this study cannot provide the answer. "The isolation of egg precursor cells and mitochondrial extraction were processes performed by the external company," explained Labarta. "Our embryologists received the mitochondrial solution and injected it with the sperm at the time of ICSI. Thus, our team could never see the egg , but worked with a solution presumably containing the isolated from them."

So not yet time, it seems, to rewrite biology. Nor yet to define with certainty any method which can actually improve egg quality.

Explore further: A commonly offered add-on treatment for IVF fails to provide any benefit in a large randomized trial

More information: Abstract O-210, Tuesday 3 July 2018 - Autologous mitochondrial transfer as a complementary technique to ICSI to improve oocyte and embryo quality in IVF patients. A randomized pilot study.

Related Stories

A commonly offered add-on treatment for IVF fails to provide any benefit in a large randomized trial

July 3, 2018
An add-on treatment commonly offered to female IVF patients to improve their chance of success has been shown in a large randomised trial to be of no value. "Endometrial scratch", a technique whereby a small scratch or tissue ...

More than 8 million babies born from IVF since the world's first in 1978

July 3, 2018
Forty years after the birth of Louise Brown, the world's first test-tube baby, an international committee monitoring progress in assisted reproduction reports today that the global total of babies born as a result of IVF ...

Sub-fertility in men treated with ICSI associated with an increased risk of prostate cancer

July 3, 2018
Subfertile men who have received fertility treatment with the microinjection technique of ICSI (intracytoplasmic sperm injection) have been found at a significantly greater risk of prostrate cancer, according to an analysis ...

Spain now sets the pace of assisted reproduction in Europe with more than 100,000 treatments a year

July 4, 2017
Spain is Europe's most active country in assisted reproduction. ESHRE has collected the national registry data of ART cycles performed in Europe since 1997 and for its latest report (for 2014) found that a record 109,275 ...

Study examines if timing of IVF to avoid weekend procedures affects pregnancy success

October 25, 2017
It's unclear whether there is a need to retrieve a woman's eggs on weekends, in connection with in vitro fertilization/intracytoplasmatic sperm injection (IVF/ICSI) treatment in couples wishing to conceive. In a recent Acta ...

Mom's, not dad's, mitochondria create healthy embryos

August 29, 2017
Mammal embryos shed paternal mitochondria within days of fertilization, perhaps to ensure the offspring a healthy life, a new study shows. Researchers from the California Institute of Technology will present their findings ...

Recommended for you

Undiagnosed STIs can increase negative PMS symptoms

September 17, 2018
Women that have undiagnosed sexually transmitted infections may be at greater risk of experiencing negative premenstrual symptoms (PMS), according to new Oxford University research.

High dose folic acid does not prevent pre-eclampsia in high risk women

September 13, 2018
Taking high dose folic acid supplements in later pregnancy (beyond the first trimester) does not prevent pre-eclampsia in women at high risk for this condition, finds a randomised controlled trial published by The BMJ today.

Study finds air purifiers may benefit fetal growth

September 12, 2018
A new study led by SFU health sciences researchers Prabjit Barn and Ryan Allen reveals fetal growth may improve if pregnant women use portable air purifiers inside their homes.

Delayed childbearing is a growing source of multiple births, study shows

September 12, 2018
Starting in the 1980s, the number of multiple births—twins, triplets, quadruplets and quintuplets—steadily increased from about 20 sets per 1,000 live births to almost 35 sets per 1,000 live births in the 2010s.

Transforming pregnancy research with a smartphone app

September 5, 2018
For years, pregnant women have been underrepresented in biomedical research. Current treatments, interventions and guidelines do a poor job of taking into consideration the diverse characteristics of all pregnant women.

For women undergoing IVF, is fresh or frozen embryo transfer best?

August 21, 2018
The world's first baby born via in-vitro fertilization turned 40 years old this summer. Still, after four decades, IVF is a relatively new field with ongoing debate on how to get the best results for families who have placed ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.