A randomized control comparison study of culture media (HTF versus P1) for human in vitro fertilization

Improved Murine Blastocyst Quality and Development in a Single Culture Medium Compared to Sequential Culture Media

OBJECTIVE

Validate single versus sequential culture media for murine embryo development.

DESIGN

Prospective laboratory experiment.

SETTING

Assisted Reproduction Laboratory.

ANIMALS

Murine embryos.

INTERVENTIONS

Thawed murine zygotes cultured for 3 or 5 days (d3 or d5) in single or sequential embryo culture media developed for human in vitro fertilization.

MAIN OUTCOME MEASURES

On d3, zygotes developing to the 8 cell (8C) stage or greater were quantified using 4',6-diamidino-2-phenylindole (DAPI), and quality was assessed by morphological analysis. On d5, the number of embryos reaching the blastocyst stage was counted. DAPI was used to quantify total nuclei and inner cell mass nuclei. Localization of ubiquitin C-terminal hydrolase L1 (UCHL1) and ubiquitin C-terminal hydrolase L3 (UCHL3) was reference points for evaluating cell quality.

RESULTS

Comparing outcomes in single versus to sequential media, the odds of embryos developing to the 8C stage on d3 were 2.34 time greater (P = .06). On d5, more embryos reached the blastocyst stage (P = <.0001), hatched, and had significantly more trophoblast cells (P = .005) contributing to the increased total cell number. Also at d5, localization of distinct cytoplasmic UCHL1 and nuclear UCHL3 was found in high-quality hatching blastocysts. Localization of UCHL1 and UCHL3 was diffuse and inappropriately dispersed throughout the cytoplasm in low-quality nonhatching blastocysts.

CONCLUSIONS

Single medium yields greater cell numbers, an increased growth rate, and more hatching of murine embryos. Cytoplasmic UCHL1 and nuclear UHCL3 localization patterns were indicative of embryo quality. Our conclusions are limited to murine embryos but one might speculate that single medium may also be more beneficial for human embryo culture. Human embryo studies are needed.

Culture media for human pre-implantation embryos in assisted reproductive technology cycles

BACKGROUND

Many media are commercially available for culturing pre-implantation human embryos in assisted reproductive technology (ART) cycles. It is unknown which culture medium leads to the best success rates after ART.

OBJECTIVES

To evaluate the safety and effectiveness of different human pre-implantation embryo culture media in used for in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI) cycles.

SEARCH METHODS

We searched the Cochrane Menstrual Disorders and Subfertility Group's Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the National Research Register, the Medical Research Council's Clinical Trials Register and the NHS Center for Reviews and Dissemination databases from January 1985 to March 2015. We also examined the reference lists of all known primary studies, review articles, citation lists of relevant publications and abstracts of major scientific meetings.

SELECTION CRITERIA

We included all randomised controlled trials which randomised women, oocytes or embryos and compared any two commercially available culture media for human pre-implantation embryos in an IVF or ICSI programme.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the studies, assessed their risk of bias and extracted data. We sought additional information from the authors if necessary. We assessed the quality of the evidence using Grades of Recommendation, Assessment, Development and Evaluation (GRADE) methods. The primary review outcome was live birth or ongoing pregnancy.

MAIN RESULTS

We included 32 studies in this review. Seventeen studies randomised women (total 3666), three randomised cycles (total 1018) and twelve randomised oocytes (over 15,230). It was not possible to pool any of the data because each study compared different culture media.Only seven studies reported live birth or ongoing pregnancy. Four of these studies found no evidence of a difference between the media compared, for either day three or day five embryo transfer. The data from the fifth study did not appear reliable.Six studies reported clinical pregnancy rate. One of these found a difference between the media compared, suggesting that for cleavage-stage embryo transfer, Quinn's Advantage was associated with higher clinical pregnancy rates than G5 (odds ratio (OR) 1.56; 95% confidence interval (CI) 1.12 to 2.16; 692 women). This study was available only as an abstract and the quality of the evidence was low.With regards to adverse effects, three studies reported multiple pregnancies and six studies reported miscarriage. None of them found any evidence of a difference between the culture media used. None of the studies reported on the health of offspring.Most studies (22/32) failed to report their source of funding and none described their methodology in adequate detail. The overall quality of the evidence was rated as very low for nearly all comparisons, the main limitations being imprecision and poor reporting of study methods.

AUTHORS' CONCLUSIONS

An optimal embryo culture medium is important for embryonic development and subsequently the success of IVF or ICSI treatment. There has been much controversy about the most appropriate embryo culture medium. Numerous studies have been performed, but no two studies compared the same culture media and none of them found any evidence of a difference between the culture media used. We conclude that there is insufficient evidence to support or refute the use of any specific culture medium. Properly designed and executed randomised trials are necessary.

Embryo culture media and IVF/ICSI success rates: a systematic review

BACKGROUND The media that are used to culture human preimplantation embryos are considered to be an important factor for the success rates of IVF/ICSI. Here, we present a systematic review of randomized controlled trials (RCTs) on the effect of culture media on IVF/ICSI success rates. METHODS RCTs published between January 1985 and July 2012 were eligible for inclusion. The primary outcome was live birth. Secondary outcomes were health of babies born, ongoing pregnancies, clinical pregnancies, miscarriages, multiple pregnancies, implantation rate, cryopreservation rate, embryo quality and fertilization rate. For those media that were evaluated in more than one comparison, an unconventional meta-analysis was performed by pooling the data of the media they were compared to. RESULTS Twenty-two RCTs were included that evaluated 31 different comparisons. Conventional meta-analysis was not possible for any of the outcomes as nearly all trials compared different culture media. Only four trials reported on live birth, and one of them reported a significant difference. Nine trials reported on ongoing and/or clinical pregnancy rates, of which four showed a significant difference. Pooling the data did not reveal a superior culture medium. CONCLUSIONS It is yet unknown what culture medium leads to the best success rates in IVF/ICSI. Given the potential importance of culture media for treatment outcome, rigorously designed RCTs are needed for currently available, as well as newly introduced culture media.

Side-by-side comparison of five commercial media systems in a mouse model: suboptimal in vitro culture interferes with imprint maintenance

Assisted reproductive technologies (ARTs) are becoming increasingly prevalent and are generally considered to be safe medical procedures. However, evidence indicates that embryo culture may adversely affect the developmental potential and overall health of the embryo. One of the least studied but most important areas in this regard is the effects of embryo culture on epigenetic phenomena, and on genomic imprinting in particular, because assisted reproduction has been linked to development of the human imprinting disorders Angelman and Beckwith-Wiedemann syndromes. In this study, we performed side-by-side comparisons of five commercial embryo culture systems (KSOMaa, Global, Human Tubal Fluid, Preimplantation 1/Multiblast, and G1v5PLUS/G2v5PLUS) in relation to a best-case (in vivo-derived embryos) and a worst-case (Whitten culture) scenario. Imprinted DNA methylation and expression were examined at three well-studied loci, H19, Peg3, and Snrpn, in mouse embryos cultured from the 2-cell to the blastocyst stage. We show that embryo culture in all commercial media systems resulted in imprinted methylation loss compared to in vivo-derived embryos, although some media systems were able to maintain imprinted methylation levels more similar to those of in vivo-derived embryos in comparison to embryos cultured in Whitten medium. However, all media systems exhibited loss of imprinted H19 expression comparable to that using Whitten medium. Combined treatment of superovulation and embryo culture resulted in increased perturbation of genomic imprinting, above that from culture alone, indicating that multiple ART procedures further disrupt genomic imprinting. These results suggest that time in culture and number of ART procedures should be minimized to ensure fidelity of genomic imprinting during preimplantation development.

An auto-controlled prospective comparison of two embryos culture media (G III series versus ISM) for IVF and ICSI treatments

PURPOSE

To compare the effects of 2 different media on embryo morphology and development at days 2/3.

METHOD

Six hundred seventy-six attempts from 512 couples were included in this prospective auto-controlled study. Sibling oocytes of all couples undergoing an IVF (n = 286) or ICSI (n = 390) attempt were randomly assigned to either GIII series (Vitrolife) or ISM (Medicult) media. Primary end points were fertilization and embryo morphology rates.

RESULTS

Fertilization rates in GIII series and ISM (IVF: 59.9 vs 62.0% and ICSI: 65.7 vs 66.8%) respectively were not different. GIII series showed an increase, compared to ISM, of early cleavage rate, (IVF: 25.8 vs 16.2% (p = 0.005); ICSI: 40.8 vs 25.5% (p < 0.0001), and good embryo morphology rate at day 2 [IVF: 64.6 vs 57.3% (p = 0.01); ICSI: 74.2 vs 69.4 (p = 0.03)] and at day 3 [IVF: 57.5 vs 49.0% (p = 0.02); ICSI: 67.2 vs 61.6% (p = 0.01)].

CONCLUSIONS

Embryo morphology at days 2/3 was significantly enhanced when the embryos were cultured in GIII series.

Implantation failure following in-vitro fertilization

PURPOSE OF REVIEW

Embryo implantation remains the rate-limiting step in assisted conception programmes. Factors affecting the interactions between blastocyst and endometrium are subjects of current research and, sadly, have also been the subjects of much confusion. This review aims to present current thinking on factors affecting embryo development, endometrial receptivity during and around the implantation window and the evidence for and against various proposed treatment options

RECENT FINDINGS

Age-related aneuploidies of the sex chromosomes and several other autosomes are now thought to adversely affect oocyte and embryo quality, leading to repeat in-vitro fertilization failures. Several small controlled trials have suggested improvements in clinical outcomes following preimplantation screening and blastocyst transfer for aneuploidy in older women. These are, however, very costly, wasteful of embryos and do not appear beneficial after the age of 40 years. Factors influencing endometrial receptivity remain largely unresolved. New technology using microarrays for gene expression profiling and progesterone receptor polymorphism may shed more light in the near future.

SUMMARY

Giant strides have been made in studying the causative factors of implantation failure, but these have not been matched by therapeutic solutions. Many proposed interventions are of unproven value, yet can have harmful side-effects.

Human embryonic stem cell methyl cycle enzyme expression: modelling epigenetic programming in assisted reproduction?

To investigate a possible mechanism for inducing epigenetic defects in the preimplantation embryo, a human embryonic stem cell model was developed, and gene expression of the key methyl cycle enzymes, MAT2A, MAT2B, GNMT, SAHH, CBS, CGL, MTR, MTRR, BHMT, BHMT2, mSHMT, cSHMT and MTHFR was demonstrated, while MAT1 was barely detectable. Several potential acceptors of cycle-generated methyl groups, the DNA methyltransferases (DNMT1, DNMT3A, DNMT3B and DNMT3L), glycine methyltransferase and the polyamine biosynthetic enzymes, SAM decarboxylase and ornithine decarboxylase, were also expressed. Expression of folate receptor alpha suggests a propensity for folate metabolism. Methotrexate-induced depletion of folate resulted in elevated intracellular homocysteine concentration after 7 days in culture and a concomitant increase in cysteine and glutathione, indicating clearance of homocysteine through the transulphuration pathway. These studies indicate that altered methyl group metabolism provides a potential mechanism for inducing epigenetic changes in the preimplantation embryo.