Embryo Transfer Medium Research Articles

Recombinant bovine interferon-τ enhances in vitro development of bovine embryos by upregulating expression of connexin 43 and E-cadherin

Interferon-τ (IFNT), produced in ruminants by embryonic trophoblastic cells before implantation, is involved in the maternal recognition of pregnancy. It is a pleiotropic molecule that alters the synthesis of endometrial proteins and inhibits the proliferation of some cells. The present study investigated the effects of recombinant bovine IFNT on the development of early-stage bovine embryos and the molecular mechanism underlying this effect. This study demonstrated that expression of mRNA encoding type I IFN receptor subunits was detectable from d 4 to 8 in in vitro fertilized (IVF) bovine embryos. A considerable number of IVF (n=1,941) and parthenogenetic activated (n=1,552) bovine embryos demonstrated that supplementing the culture medium with IFNT (100ng/mL) produced a greater percentage of blastocysts, and the total cell number within the resulting blastocysts was higher. In addition, IFNT upregulated the expression levels of both mRNA and protein for connexin 43 (GJA1) and E-cadherin (CDH1) and expression levels for granulocyte-macrophage colony-stimulating factor and insulin-like growth factor 2 mRNA but not for their proteins in d 8 embryos. However, IFNT inhibited mRNA expression for leukemia inhibitory factor (LIF), LIF receptor α, and the sodium/potassium-transporting ATPase subunit β-1. We concluded that IFNT promoted the development of bovine embryos by upregulating the expression of GJA1 and CDH1. Thus, supplementing embryo cultures or transfer medium with IFNT may stimulate embryo development and improve embryo transfer efficiency.

Adherence compounds in embryo transfer media for assisted reproductive technologies

This is an update of a Cochrane review first published in The Cochrane Library (2010, Issue 7).To increase the success rate of assisted reproductive technologies (ART), adherence compounds such as hyaluronic acid (HA) and fibrin sealant have been introduced into subfertility management. Adherence compounds are added to the embryo transfer medium to increase the likelihood of embryo implantation, with the potential for higher clinical pregnancy and live birth rates. To determine whether embryo transfer media containing adherence compounds improved live birth and pregnancy rates in ART cycles. The Menstrual Disorders and Subfertility Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) and MEDLINE, EMBASE and PsycINFO electronic databases were searched (up to 13 November 2013) to look for publications that described randomised controlled trials on the addition of adherence compounds to embryo transfer media. Furthermore, reference lists of all obtained studies were checked, and conference abstracts were handsearched. Only truly randomised controlled trials comparing embryo transfer media containing functional (e.g. 0.5 mg/ml HA) concentrations of adherence compounds versus transfer media containing low or no concentrations of adherence compounds were included. The adherence compounds that were identified for evaluation were HA and fibrin sealant. Two review authors selected trials for inclusion according to the above criteria, after which two review authors independently extracted the data for subsequent analysis. Statistical analysis was performed in accordance with the guidelines developed by The Cochrane Collaboration. Seventeen studies with a total of 3898 participants were analysed. One studied fibrin sealant, and the other 16 studied HA. No evidence was found of a treatment effect of fibrin sealant as an adherence compound. For HA, evidence of a positive treatment effect was identified in the six trials that reported live birth rates (odds ratio (OR) 1.41, 95% confidence interval (CI) 1.17 to 1.69; six RCTs, N = 1950, I(2) = 0%, moderate-quality evidence). Furthermore, the 14 trials reporting clinical pregnancy rates showed evidence of treatment benefit when embryos were transferred in media containing functional concentrations of HA (OR 1.39, 95% CI 1.21 to 1.60; 14 RCTs, N = 3452, I(2) = 46%, moderate-quality evidence) as compared with low or no use of HA. The multiple pregnancy rate (OR 1.86, 95% CI 1.49 to 2.31; five RCTs, N = 1951, I(2) = 0%, moderate-quality evidence) was significantly increased in the high HA group, but no significant differences in adverse event rates were found (OR 0.74, 95% CI 0.49 to 1.12; four RCTs, N = 1525, I(2) = 0%, moderate-quality evidence). Evidence suggests improved clinical pregnancy and live birth rates with the use of functional concentrations of HA as an adherence compound in ART cycles. However, the evidence obtained is of moderate quality. The increase in multiple pregnancy rate may be the result of use of a combination of an adherence compound and a policy of transferring more than one embryo. Further studies of adherence compounds with single embryo transfer need to be undertaken.

Influence of EmbryoGlue on the implantation of embryo and pregnancy outcome in vitro fertilization-embryo transfer

To study the influence of EmbryoGlue on the implantation of embryo and pregnancy outcome in vitro fertilization (IVF)-embryo transfer (ET). From August 2010 to January 2011, 243 infertile patients in Reproductive Medical Center of Tianjin Medical University General Hospital who underwent IVF or intracytoplasmic sperm injection (ICSI) were divided into two groups, including 129 cases used EmbryoGlue as the embryo transfer medium in experimental group and 114 cases used G-2 as embryo transfer medium in control group. Pregnancy outcome were compared between two groups. (1) The female age, IVF/ICSI constituent ratio, previous failure cycles and infertile factors of patients did not show statistical difference between experimental group and control group (P > 0.05). (2) The implantation rate of women in experimental group increased significantly compared with the control group [30.4% (85/280) vs. 18.8% (48/255), P < 0.05]; Clinical pregnancy rate increased significantly compared with the control group [48.8% (63/129) vs.34.2%(39/114), P < 0.05]; Multiple pregnancy rate increased significantly compared with the control group [34.9% (22/63) vs. 20.5% (8/39), P < 0.05]; Ectopic pregnancy rate decreased significantly compared with the control group [4.8% (3/63) vs. 17.9% (7/39), P < 0.05]. EmbryoGlue can facilitate embryo implantation in IVF-ET and reduce the occurrence of ectopic pregnancy.

Synthetic media for culture, freezing and vitrification of bovine embryos

Media designed for the recovery, holding and cryopreservation of bovine and equine embryos are available from several commercial sources. In years past, some of these media contained bovine serum, although inclusion of serum in embryo transfer media is now largely discontinued due to issues relating to storage and biosecurity. Currently, bovine serum albumin (BSA) is included in most commercially manufactured media intended for use in embryo transfer (ET). Although BSA poses less risk than serum for the transmission of infectious disease, its inclusion still entails risk of viral contamination. The present review briefly describes the various components of ET media and the development of efficacious ET media containing no products of animal origin. An evaluation of the efficacy of recovery, holding, slow controlled freezing and vitrification media in both research and commercial ET embryo transfer settings is also presented.

Y a-t-il un intérêt à utiliser un milieu de transfert embryonnaire enrichi en acide hyaluronique lors de tentatives de FIV/ICSI ?

ObjectiveSeveral studies have been performed up to date, in order to assess whether the addition of hyaluronan (HA) in human embryo culture could improve the probability of pregnancy, leading, however, to controversies. The aim of the present study was to analyze whether the use of a HA-enriched transfer medium increases clinical pregnancy (PR) and implantation rates (IR), compared with the use of a conventional transfer medium. Patients and methodsAll IVF/ICSI attempts from unselected women were included from January 2009 to July 2009 (study group). All embryo transfers (ET) were performed using a HA-enriched media. IVF outcomes of this series were compared to those of a retrospective series, including continuous IVF/ICSI attempts from January 2008 to July 2008 where ET were classically performed (control group). Primary endpoints were PR and IR, compared firstly in all patients of the study and control groups and then regarding woman's age and presence of previous implantation failures. ResultsIn all, 292 (study group) and 296 (control group) IVF/ICSI attempts were included. PR (32.9%) and IR (22.2%) were significantly increased in the study group compared with those of the control group (PR=25.0%; IR=15.4%; p<0.05). We observed that PR and IR were statistically increased only in subgroups of women ≥35 years or in case of at least one previous implantation failure (p<0.05). Discussion and conclusionThe use of a HA-enriched embryo transfer medium is beneficial since associated with increased PR and IR. This type of media should be used in infertile women ≥35 years or needing at least a second IVF/ICSI attempt.

Does hyaluronan improve embryo implantation?

Taking into consideration the increasing interest on hyaluronan and its biological as well as physiological properties, this review will focus on the role of this molecule in human embryo implantation. Several studies have been performed up to date in order to assess whether the addition of hyaluronan in the human embryo culture system can improve pregnancy and implantation rates, including one retrospective and six randomized controlled trials. On the one hand, four of those studies showed significant increase in clinical pregnancy and/or implantation rates after using embryo transfer medium containing high concentration of hyaluronan. On the other hand, three studies did not demonstrate any significant improvement in clinical pregnancy and implantation rates. However, regardless of statistical significance, almost all studies demonstrate higher pregnancy and implantation rates after using embryo transfer medium containing high concentration of hyaluronan. Up to date, the results regarding the role of hyaluronan in human embryo implantation are still conflicting and, thus, further prospective randomized clinical trials are necessary to draw solid conclusions.

Effect of Volume of Non-Surgical Embryo Transfer Medium on Ability of Porcine Embryos to Survive to Term

Non-surgical embryo transfer is a promising method for improving efficiency in the pork industry and also for biotechnology applications, such as in vitro embryo production, transgenesis and cloning. Several groups have reported successful piglet production using an artificial insemination catheter or flexible catheter designed for this procedure; however, the efficiency of the technique is still low. The critical points that need to be addressed in order to improve this procedure are (1) the embryo deposition site and (2) volume of transfer medium associated with the embryos; however, the latter has not yet been examined systematically. In the present study, we evaluated the effect of the volume of non-surgical embryo transfer medium on the ability of porcine embryos to survive to term by using a recently produced flexible catheter. The catheter consists of a guide and an injector. Blastocysts 200-230 mum in diameter were collected from donor gilts and transferred to recipient gilts. The time required for the completion of embryo transfer using this catheter was 14.6 +/- 3.9 min. The tip of the injector was determined by laparotomy to be located in a uterine horn 20-30 cm anterior from the branching point of the uterus body. We transferred 17.0-17.3 embryos with different volumes of medium (1.6, 3.2 and 10 ml) into each of 5, 4 and 4 recipients, respectively, and pregnancy was confirmed in 4, 3 and 1 of these recipients, respectively. Three recipients in the 1.6 ml group farrowed a total of 19 piglets (4, 5 and 10 piglets, respectively). These results suggest that successful non-surgical embryo transfer is affected by the volume of transfer medium.

Effect of hyaluronan-enriched transfer medium on implantation and pregnancy rates after day 3 and day 5 embryo transfers: a prospective randomized study

To analyze whether the use of a hyaluronan-enriched transfer medium (HETM) increases rates of implantation (IRs) and clinical pregnancy (CPRs), compared with the use of a conventional transfer medium after day 3 and day 5 embryo transfers. Prospective randomized controlled trial. An assisted reproduction program in a private tertiary-care hospital in Turkey. A total of 1,282 consecutive fresh embryo transfer cycles (825 day 3 and 457 day 5) were randomly allocated into two groups. In 639 women, ET was effected with HETM, and in 643, it was effected with a conventional embryo transfer medium. Embryo transfer using HETM or conventional embryo transfer medium. Clinical pregnancy rates and IRs were compared with regard to day of embryo transfer, women's age, quality of the transferred embryos, and presence of previous implantation failures. Overall CPRs and IRs significantly increased with the use of HETM (CPR: 54.6% vs. 48.5%, odds ratio: 1.28, 95% confidence interval: 1.03-1.59; IR: 32% vs. 25%, odds ratio: 1.43, 95% confidence interval: 1.23-1.66, for HETM and control groups, respectively). The number needed to treat (NNT) for one additional pregnancy with routine use of HETM was 17. The beneficial effect was more prominent in women who were >35 years of age (NNT = 7), in women who had previous failed cycles (NNT = 7), and in women who had poor-quality embryos (NNT = 8). The enrichment of transfer medium with hyaluronan increases CPRs and IRs, both for day 3 and day 5 embryo transfers. The beneficial effect was most evident in women who were >35 years of age, in women who had only poor-quality embryos available for transfer, and in women who had previous implantation failures.

Impact of EmbryoGlue as the embryo transfer medium

Routine use of EmbryoGlue did not significantly improve pregnancy or implantation rates in nonselected patients receiving either a day 3 or day 5 embryo transfer compared with standard culture media. Future prospective randomized studies need to be performed to determine whether EmbryoGlue is beneficial in a selected patient population.

A randomized clinical trial comparing recombinant hyaluronan/recombinant albumin versus human tubal fluid for cleavage stage embryo transfer in patients with multiple IVF-embryo transfer failure

We aimed to examine the efficacy of using an embryo transfer medium enriched with hyaluronan (HA) to improve implantation in a selected group of patients aged <43 years with repeated (>4) implantation failures after IVF-embryo transfer. About 101 patients, meeting our selection criteria, were randomly allocated to undergo embryo transfer either using our routine embryo transfer medium without HA (control group) or a HA enriched commercial embryo transfer medium (study group). The primary outcome was clinical pregnancy rate. After a similar treatment protocol, the ovarian hormonal response, the mean number of ova retrieved and injected per patient, fertilization and cleavage rates and mean embryo quality were comparable between the study and control groups. Although a similar number of embryos was transferred in both groups (3.1 +/- 0.7 versus 2.9 +/- 0.6, mean +/- SD), a significantly higher implantation rate (16.3% versus 4.8%, P = 0.002) and clinical pregnancy rate (35.2% versus 10.0%, P = 0.004) and delivered or ongoing pregnancy rate (31.3% versus 4.0%, P = 0.0005) were observed in the study group. When mean implantation rate per patient was calculated, the difference between the study (0.148 +/- 0.23) and control (0.04 +/- 0.13) group was significant (P = 0.003). In this selected group of patients after multiple IVF-embryo transfer failures, the use of HA enriched embryo transfer medium is beneficial.

Evaluation of a transfer medium containing high concentration of hyaluronan in human in vitro fertilization

To examine whether a high concentration of recombinant hyaluronan in the embryo transfer (ET) medium can influence pregnancy rates in humans. Retrospective, matched group study. Private and university hospital in vitro fertilization (IVF) units. Couples undergoing IVF or intracytoplasmic sperm injection (ICSI) were divided in two groups. In group 1 (402 patients), ET was performed with an ET medium containing a high concentration of recombinant hyaluronan in the presence of recombinant human serum albumin (HSA). In group 2 (425 couples), ET was performed with a medium containing a lower concentration of hyaluronan and HSA. IVF and ICSI. The two groups were compared for pregnancy rates according to the woman's age, the technique used (IVF or ICSI), the number of embryos transferred, and the day of ET. Between the two groups, no statistically significant differences were observed in the total pregnancy rates after IVF or ICSI. Similarly, the pregnancy rates did not differ between the two groups when subdivided according to the woman's age, the number of embryos transferred (one to four), or the day of ET (2, 3, or 5 after oocyte pick up). The use of an ET medium with a high concentration of hyaluronan does not appear to have any statistically significant effect on pregnancy rates.

P-257: Does embryo transfer in hyaluronan enriched transfer medium (EmbryoGlue®) improve pregnancy rate in IVF?

Hyaluronan is a major glycosaminoglycan in uterine fluid and has been shown to increase cell-cell and cell-matrix adhesion, therefore may improve embryos apposition and attachment. Previous studies in mice and humans have revealed that high hyaluronan concentration in embryo transfer medium increases implantation and pregnancy rates. However, preliminary results presented by us last year didn’t show advantage in performing embryo transfer with hyaluronan enriched medium. This study is aimed to further evaluate whether the use of embryo transfer medium enriched with hyaluronan (EmbryoGlue® - Vitrolife, Sweden) improves pregnancy rate in IVF treatment.

Efficacy of a human embryo transfer medium: a prospective, randomized clinical trial study

The aim of this prospective, randomized trial was to evaluate the efficacy of Embryo-Glue as a human embryo transfer medium in IVF/ICSI cycles. A total of 815 nonselected patients undergoing IVF/ICSI treatment between September 2003 and February 2004 were randomly allocated into the test (417 patients) and the control (398 patients) groups. In both groups, embryos were cultured in G-1ver 3, supplemented with 10% recombinant human albumin. On the day of embryo transfer (day 3), the best or good quality embryos were selected for intrauterine transfer. In the test group, the selected embryos were treated with EmbryoGlue prior to the transfer, whereas in the control group they were transferred without any treatment. The patients' characteristics such as age and the number of ART cycles and also the number of patients in each indication of infertility and the number of embryos selected for transfer were all similar between the two groups. In the test group, the clinical pregnancy rate in the tubal factors and the implantation rate in the tubal factors and recurrent implantation failures increased significantly compared with those in the control group. In the test group, life birth and the triplet delivery rates increased significantly compared with those in the control group. EmbryoGlue is a useful embryo transfer medium, and at least in some infertile patients it can improve clinical implantation and ongoing pregnancy rates.

Embryo Transfer in Hyaluronan Enriched Transfer Medium Does Not Improve Pregnancy Rate in IVF Treatment

Hyaluronan is a major glycosaminoglycan in uterine fluid that has been shown to increase cell-cell and cell-matrix adhesion, and may therefore improve embryo apposition and attachment. Previous studies in mice and humans have revealed that high hyaluronan concentration in embryo transfer medium increases implantation and pregnancy rates. Our study is aimed to evaluate whether the use of embryo transfer medium enriched with hyaluronan (EmbryoGlue - Vitrolife, Gothenburg, Sweden) improves implantation and pregnancy rate in fresh embryo transfers.

Hyaluronan enriched transfer medium is more beneficial in advanced maternal age

The purpose of the study was to evaluate the efficacy of hyaluronan enriched embryo transfer medium (EmbryoGlue-Vitrolife, Gothenburg) on the outcome of assisted reproductive techniques in different female age groups.

Hyaluronic acid can successfully replace albumin as the sole macromolecule in a human embryo transfer medium

Objective To examine the effect on pregnancy and implantation rates when highly purified, fermentation-based hyaluronic acid was the only macromolecule supplement to the transfer medium in a human IVF program. Design Prospective randomized study. Setting In vitro fertilization center in an academic medical institution. Patient(s) Eighty patients were included in this prospective randomized double blind study. Inclusion criteria were age ≤35 years, the availability of at least three embryos eligible for transfer on day 3 after fertilization, and no more than three previous embryo transfer attempts. Intervention(s) All embryos were cultured in P1 medium containing 10% synthetic serum substitute (SSS) until day 3. Patients were randomly allocated to two groups; in treatment group A (40 patients), embryos were transferred to P1 medium supplemented with 0.5 mg/mL hyaluronic acid for 5–10 min before their intrauterine transfer. In the control group B (40 patients), embryos were transferred, as routinely performed, in P1 medium containing 10% SSS. Main outcome measure(s) Clinical pregnancy and implantation rates. Result(s) The mean age of the female partner was 28.7 ± 3.3 years and 29.7 ± 3.8 years for groups A and B, respectively. In group A, 103 embryos were transferred and in group B, 97 embryos were transferred for a similar mean number of 2.6 ± 0.6 and 2.4 ± 0.5 embryos/transfer, respectively. Twenty-five pregnancies were achieved in group A, and 21 pregnancies in group B. This led to a comparable clinical pregnancy and implantation rates of 62.5% and 34% as compared to 52% and 26.8% for groups A and B, respectively. Conclusion(s) Hyaluronic acid can successfully replace albumin as a sole macromolecule in a human embryo transfer medium and result in high pregnancy and implantation rates. The use of this supplement is an important step in the development of human embryo culture media free of blood-derived additives.

Increased hyaluronan concentration in the embryo transfer medium results in a significant increase in human embryo implantation rate

Objective: The levels of hyaluronan, a glycosaminoglycan, in the female reproductive tract increase up to the time of implantation. Previous studies using the mouse model have revealed that the presence of hyaluronan in the embryo transfer medium significantly increases resultant implantation rates. The aim of this study was therefore to determine the effect of hyaluronan present in human embryo transfer medium on subsequent implantation rate (fetal heart beat, FHB).

Effect of Hyaluronic Acid (HA) Supplemented to Transfer Medium on the Implantation Rate of Human Embryos in IVF-ET Program

Objectives: HA is a physiological component of the cumulus and of the female and male reproductive tract. The concentration of HA increases at the time of implantation in the mouse embryo. Recently, Gardner et al. (1999) reported that the supplement of HA to the transfer medium in mice resulted in an increased implantation rate. However, the effectiveness of HA in human ART has not been reported. Therefore, the aim of this study was to examine the effect on the implantation and pregnancy when HA was supplemented to the embryo transfer (ET) medium.Design: This study was performed in both 3-day ET group and 5-day ET group from 21, Dec. 1999 to 21 Jan. 2000. Cleavage-stage embryos or blastocyst stage embryos were selected maximum 4 or maximum 3 in each group for ET, respectively, and randomly treated with HA or not. The number of patients that assigned to each treatment were as described in below Table.Materials and Methods: All transferred embryos were co-cultured with cumulus cell layers in 10μl droplets of YS medium supplemented with 20% hFF. ETs were carried out into patient’s uterus on day 3 or on day 5. On ET day, the patients were randomly divided into two groups. One was a treatment group; the other was an untreatment group. The concentration of treated HA in this study was 0.5 mg/ml in YS medium containing 20% hFF. The treated time was 1∼10 min prior to transfer. The Implantation and pregnancy were assessed by observation of G-sac at 6–7 weeks post-insemination.Results: The result was as follows: Tabled 1ETAddition of HANo. of patientsNo. of transferred embryosMean no. of transferred embryosNo. (%) of G-sac.No. (%) of clinical pregnancy3 Day ET−612313.7927 (11.7)17 (27.9)+481683.5025 (14.9)15 (31.3)5 Day ET−27602.2216 (26.7)12 (44.4)+41922.2430 (32.6)23 (56.1) Open table in a new tab Conclusions: We concluded that performance of embryo transfer with a transfer medium containing HA could improve the implantation and pregnancy rate in human ART program, as found in the murine model. Objectives: HA is a physiological component of the cumulus and of the female and male reproductive tract. The concentration of HA increases at the time of implantation in the mouse embryo. Recently, Gardner et al. (1999) reported that the supplement of HA to the transfer medium in mice resulted in an increased implantation rate. However, the effectiveness of HA in human ART has not been reported. Therefore, the aim of this study was to examine the effect on the implantation and pregnancy when HA was supplemented to the embryo transfer (ET) medium. Design: This study was performed in both 3-day ET group and 5-day ET group from 21, Dec. 1999 to 21 Jan. 2000. Cleavage-stage embryos or blastocyst stage embryos were selected maximum 4 or maximum 3 in each group for ET, respectively, and randomly treated with HA or not. The number of patients that assigned to each treatment were as described in below Table. Materials and Methods: All transferred embryos were co-cultured with cumulus cell layers in 10μl droplets of YS medium supplemented with 20% hFF. ETs were carried out into patient’s uterus on day 3 or on day 5. On ET day, the patients were randomly divided into two groups. One was a treatment group; the other was an untreatment group. The concentration of treated HA in this study was 0.5 mg/ml in YS medium containing 20% hFF. The treated time was 1∼10 min prior to transfer. The Implantation and pregnancy were assessed by observation of G-sac at 6–7 weeks post-insemination. Results: The result was as follows: Tabled 1ETAddition of HANo. of patientsNo. of transferred embryosMean no. of transferred embryosNo. (%) of G-sac.No. (%) of clinical pregnancy3 Day ET−612313.7927 (11.7)17 (27.9)+481683.5025 (14.9)15 (31.3)5 Day ET−27602.2216 (26.7)12 (44.4)+41922.2430 (32.6)23 (56.1) Open table in a new tab Conclusions: We concluded that performance of embryo transfer with a transfer medium containing HA could improve the implantation and pregnancy rate in human ART program, as found in the murine model.

Evolution of a culture protocol for successful blastocyst development and pregnancy.

A cell-free culture system was designed for human embryo development to the blastocyst stage by testing a range of culture conditions in a series of protocols. The culture system that was evolved has a brief 1 h exposure to spermatozoa and then culture of the pronucleate zygote for 2 days in IVF-50 medium. Two or three embryos were cultured together in 20 microl microdrops of medium under oil. Embryos were then regrouped and two or three at a similar stage were cultured together in 50 microl microdrops of Gardner's G2 medium under oil from days 3 to 5. Embryos were transferred to fresh G2 medium on day 5 and cultured for a further 1 or 2 days (day 6 or 7). No serum was used in any of the cultures. The embryo transfer medium and G2 medium were supplemented with human serum albumin. The zonae of all blastocysts to be transferred to patients were completely removed enzymatically. Using this protocol, 52% of zygotes developed to blastocysts and 34 out of 35 patients treated received 82 blastocysts and 11 morulae on day 5 or 6. Twenty-one fetal sacs with positive heartbeats (23% implantation rate) were detected in 13 ongoing pregnancies (38% pregnancy rate/transfer or 37%/patient treated). We anticipate that further improvements in embryo development and the selection of viable embryos can be achieved using this simple and effective culture system.

A mouse embryo culture system for quality control testing of human in vitro fertilization and embryo transfer media and fetal cord sera

AbstractSwiss white mice were superovulated, mated, and sacrificed to recover two‐cell embryos that were cultured in Ham's F‐10 supplemented with 15% fetal serum. In 16 experiments, media enriched with fetal bovine serum (FBS) supported blastocyst development from 80% ± 19% (mean ± S.D.) of two‐cell embryos. Culture media + FBS was the positive control when 74 batches of heat‐inactivated human fetal cord serum (hFCS) were tested. Statistical analyses indicated two distinct populations: 49 hFCS promoted blastocyst formation and 25 hFCS grew fewer blastocysts. In five studies, 35/47 two‐cell embryos recovered from mice oviducts in media + FBS and immediately incubated formed blastocysts (75% ± 10%). In six comparison studies where the recovered embryos stood at room temperature for 30 minutes before incubation, only 18/57 (29% ± 21%) became blastocysts. When the colony was housed for 1 week in rooms with Shell No Pest Strips as treatment for mites, only 11/125 two‐cell embryos became blastocysts (9%). In contrast, animals housed in quarters decontaminated with chlorine bleach had reduced breeding efficiency and produced fewer two‐cell embryos. We conclude that (1) Ham's F‐10 + FBS is an excellent positive control to test new batches of hFCS; (2) hFCS that supports blastocyst formation from ≥75% of two‐cell embryos is adequate for human use; (3) pesticide treatment of breeding colonies and cooling of murine embryos during harvest both impaired in vitro blastocyst development; and (4) chlorine bleach cleansing of animal quarters reduced the number of successful matings.