Frozen-thawed Single Blastocyst Transfer Research Articles

Clinical and ongoing pregnancy rates are improved by the addition of letrozole in the hormone replacement cycles undergoing the frozen-thawed single blastocyst transfer

pregnancy is defined by ultrasonographic demonstration of fetal cardiac activity. Implantation rate is defined as total gestational sacs divided by total embryos transferred in each category. CONCLUSION: These data suggest that extended embryo culture to day 5 does not adversely affect embryo efficiency in a select group of women with only 6 zygotes and does not pose a detrimental effect on cumulative live birth rate. Additionally, a significant decrease in cumulative twin delivery rate is achieved by this strategy if single embryo transfer is used frequently for day 5 ETs. This may translate to a safer IVF practice strategy in prevention of multiple pregnancies, including twins.

The optimal endometrial preparation for frozen-thawed single embryo transfer in a natural cycle: a retrospective analysis

Single embryo transfer (SET) is the best method for preventing multiple births. The purpose of this study is to evaluate pregnancy outcomes with or without luteal phase support (LPS) of frozen-thawed single blastocyst transfer (SBT) treatment performed in natural cycles. The study retrospectively analyzed 966 frozen-thawed SBT in natural cycles with or without LPS performed between the periods January 2010 to April 2013. Oral chlomadinone acetate (Lutoral®) was given daily during the luteal phase. The outcomes of frozen-thawed SBT treatment including demographic data, clinical pregnancy rates and miscarriage rates, were compared with or without LPS. Ovulation was determined by the LH surge, progesterone (P4) levels and ultrasonography. And all patients underwent ovarian stimulation with human chorionic gonadotrophin (hCG). In order to determine whether the P4 levels after ovulation are associated with clinical pregnancy rate or miscarriage rate, we analyzed P4 levels 2 days after ovulation in 383 cycles out of 966cycles with or without LPS. Post ovulation P4 levels were divided into four groups (with (+), without (-) LPS): Low (L+, L-), 1.4-4.4ng/ml; Middle Low (ML+, ML-), 4.5-5.5ng/ml; Middle High P4 (MH+, MH-), 5.6-7.5ng/ml and High (H+, H-), 7.6-14.8ng/ml. There were no significant differences in the patients’ demographic data (age, basal FSH and embryo quality), clinical pregnancy rate (42.5% vs. 38.0%, p=0.150) and miscarriage rate (24.7% vs. 20.3%, P=0.296), between the groups. On the second comparison (383 cycles), a strong tendency of increased clinical pregnancy rates were observed in the high P4 levels group compared to the low P4 levels group (51.1% (H-) vs. 31.9%(L-), p = 0.059) and (42.1% (H+) vs. 28.0%(L+), p=0.131), but no difference in the miscarriage rates were noted (26.7% (H-) vs. 25.0% (L-), p=0.908) and (37.5% (H+) vs. 23.8% (L+), p=0.367). The pregnancy outcomes of natural cycle frozen-thawed SBT were similar regardless of LPS. Our results suggest that LPS with oral chlomadinone acetate may not improve the clinical pregnancy nor decrease miscarriage rate. Patients with low levels of P4 might need additional interventions in order to achieve higher pregnancy rates. Our findings suggest that 2-day post ovulation levels ≥ 7.6 ng/ml of P4 provide an optimal endometrial environment. However, we need further studies to determine the optimal treatment for patients with low P4 levels to undergo frozen thawed SBT in a natural cycle.

The clinical significance of blastocyst grade at post-thawing: from an analysis of 2,425 single frozen-thawed blastocyst transfer cycles

The clinical significance of blastocyst grade at post-thawing: from an analysis of 2,425 single frozen-thawed blastocyst transfer cycles

Impact of frozen-thawed single-blastocyst transfer on maternal and neonatal outcome: an analysis of 277,042 single-embryo transfer cycles from 2008 to 2010 in Japan

To evaluate the relationship between frozen-thawed single blastocyst transfer (BT) and maternal and neonatal outcomes of pregnancy. Retrospective analysis. Japanese nationwide registry of assisted reproductive technology (ART) with mandatory reporting for all ART clinics in Japan. Registered from 2008 through 2010 undergoing single embryo transfer cycles (n = 277,042). None. Rates of preterm birth (PTB; <37 weeks' gestation), low birth weight (LBW; <2,500 g), small for gestational age (SGA), large for gestational age (LGA), placenta previa, placenta abruption, placenta accreta, and pregnancy-induced hypertension (PIH) after fresh/frozen-thawed and cleaved-embryo/blastocyst transfers were performed. Frozen-thawed embryo transfer (FET) was associated with a significantly reduced occurrence of PTB, LBW, and SGA but increased rate of LGA. FET was also associated with a higher incidence of placenta accreta (odds ratio 3.16) and PIH (odds ratio 1.58). BT was associated with a significantly decreased rate of SGA and increased rate of LGA. There was no significant association between BT and maternal complications. Frozen-thawed BT is associated with improved general perinatal outcomes of pregnancy but significantly increased maternal risks of placenta accreta and PIH. This finding requires further investigation to assure maternal safety of patients undergoing ART treatment.

Establishment of day 7 blastocyst criteria for frozen-thawed single blastocyst transfer (c-SBT)

We have previously reported that higher implantation rates were obtained after frozen thawed single blastocyst transfer (c-SBT) when the blastocyst was vitrified at expanded stage around diameter of 180μm on day 5 and 6 (Okimura et al., 2009, ASRM). The aim of this study is to establish the blastocyst criteria on day 7 for c-SBT by examining the diameter of blastocysts when c-SBT is performed and comparing outcomes of c-SBT on day 7 with fresh cleavage stage single embryo transfer (f-SET) on day 2.

Prediction of live birth in frozen-thawed single blastocyst transfer cycles by pre-freeze and post-thaw morphology

What pre-freeze and post-thaw morphological parameters can be used to predict live birth outcomes after frozen-thawed blastocyst transfer cycles? Pre-freeze blastocoele expansion and trophectoderm (TE) grade and post-thaw degree of re-expansion are the most significant predictors of live birth in frozen-thawed blastocyst transfer cycles. Currently, blastocoele re-expansion after thawing is used to indicate blastocyst cryosurvival and reproductive potential. The predictive roles of other pre-freeze and post-thaw morphological parameters are neglected. This was a retrospective study of all the patients who received a frozen-thawed single blastocyst transfer (n = 1089) at our clinic between March 2008 and October 2011. Pre-freeze morphological parameters analyzed for all blastocysts included grade of blastocoele expansion, inner cell mass and TE. A group of blastocysts (n = 243) were also graded for post-thaw parameters: degree of blastocoele re-expansion, viability and cell contour. Univariate and multivariate generalized estimating equations (GEEs) models were used to identify the confounders that statistically significantly affected live birth outcomes and to investigate the independent effect of significant pre-freeze and post-thaw morphological parameters. Stepwise logistic regression analysis was used to select the best independent morphological predictors of live birth. Pearson correlations and linear regression analyses were performed to determine the relationship between morphological parameters and possible covariates. Multivariate GEE models estimated that the odds of live birth increased by ∼36% for each grade of expansion (P = 0.0061) and decreased by 29% for blastocysts with grade B TE compared with grade A TE (P = 0.0099). Furthermore, the odds of live birth increased by ∼39% (P = 0.0042) for each 10% increase in degree of re-expansion. Blastocoele expansion and TE grade were selected as the most significant pre-freeze morphological predictors of live birth and degree of re-expansion was selected as the best post-thaw parameter for prediction of live birth. Blastocysts with poorer grades of morphology were not cryopreserved or transferred, limiting the ability to generalize our findings for grades of morphology not included in this study. Blastocysts with higher pre-freeze grades of expansion and TE, irrespective of day of cryopreservation, should be given priority when thawing. Subsequently, re-expanding blastocysts, assessed within 2-4 h, with >60% viability should be transferred. No external funding was obtained for this study. There was no competing interest. not applicable.

Pregnancy rate is improved by the addition of letrozole to hormone replacement cycle undergoing the frozen-thawed single blastocyst transfer

Pregnancy rate is improved by the addition of letrozole to hormone replacement cycle undergoing the frozen-thawed single blastocyst transfer

Outcome of stimulation of endometrium embryo transfer (SEET): from an analysis of 2,168 single frozen-thawed blastocyst transfer cycles

SEET is a variant method of blastocyst transfer, which is characterized by the injection of the embryo culture supernatant into the uterus before blastocyst transfer. We reported that SEET improved the implantation rate and the pregnancy rate in single frozen-thawed blastocyst transfer cycles (Fertil Steril 2007, 2009). Thereafter, we primarily select SEET method in frozen-thawed blastocyst transfer cycles. In this study, we retrospectively analyzed the outcome of SEET cycles in our ART center. Retrospective analysis. In this study, we collected a total of 2168 cycles of SEET cycles between January 2009 and December 2010. SEET method was performed as previously described (Fertil Steril 2007). We stratified data according to age, previous ART history, and morphological grade of blastocyst, and then investigated the clinical outcome in each group. The average age was 36.3, the average number of previous ART cycles was 2.4, and the total clinical pregnancy rate was 38.4%. The more previous ART cycles led to the lower clinical pregnancy rate (Table1). The clinical pregnancy rates of patients under 37 years of age and above 38 years of age were 45.1% and 27.8%, respectively. The clinical pregnancy rates after high grade blastocyst transfer and low grade blastocyst transfer were 57.0% and 31.9%, respectively.Tabled 1Number of previous ART cycles and Clinical outcome.No. of previous ART12345≤No. of transfer cycles141040016663129Age of patient (y)35.5 ± 4.036.2 ± 3.937.5 ± 3.639.9 ± 3.741.0 ± 3.8No. of chemical pregnancies9342451022650Implantation rate per embryo (%)66.261.361.441.338.8No. of clinical pregnancies582150591526Clinical pregnancy rate per transfer (%)41.337.535.523.820.2No. of pregnancy loss102361836pregnancy loss rate (%)17.52430.52023.1 Open table in a new tab In this study, we showed the good clinical outcome of SEET. SEET is a simple and effective method for single blastocyst transfer.

Frozen-thawed blastocyst transfer reduces ectopic pregnancy risk: an analysis of single embryo transfer cycles in Japan

To evaluate the effect of frozen-thawed blastocyst transfer on ectopic pregnancy (EP) rate. Retrospective analysis. Japanese registry of assisted reproductive medicine. Women who were registered during 2008. None. Rates of live birth, EP, and spontaneous abortion in single blastocyst and cleavage-stage ET cycles in both fresh and frozen-thawed were determined. In the frozen-thawed single blastocyst transfer cycles, 84 EPs of 10,312 clinical pregnancies (0.81%) were reported. There were 25 EPs of 1,361 clinical pregnancies (1.8%) in fresh IVF single blastocyst transfer cycles and 19 of 1,352 (1.4%) in fresh intracytoplasmic sperm injection single blastocyst transfer cycles. The rate of EPs after frozen-thawed single blastocyst transfers varied between 0.56% and 0.97% after stratification by age group. Frozen-thawed blastocyst transfers have reduced EP rates significantly compared with fresh blastocyst transfers.

Day 7 b-hCG level after frozen-thawed blastocyst transfer can be a predictor for pregnancy outcomes?

OBJECTIVE: There are only few large-scale studies about outcomes after single embryo transfer. In this time, we analyzed the results after frozen-thawed single blastocyst transfer to find out the correlation between serum β-hCG levels supplied from single implanted embryo and pregnancy outcomes.

Prediction of pregnancy and delivery rates by blastocyst morphological score and age, based on 1488 single frozen-thawed blastocyst transfer cycles

OBJECTIVE: To present an estimation of pregnancy and delivery rates after IVF or ICSI stratified by blastocyst (BL) morphology and age. DESIGN: Retrospective analysis. MATERIALS AND METHODS: A total of 1488 single frozen-thawed BL transfer cycles were analyzed. All frozen-thawed BLs used in the study were obtained in the patient's first oocytes retrieval cycles. Viable pregnancy rate (VPR; number of viable pregnancy cycles/number of transfer cycles) and delivery rate (DR; number of delivery cycles/number of transfer cycles) according to BL morphological score (Gardner system) in three different age groups; women aged 22-33, 34-37 and 38-45 years were analyzed. RESULTS: The quality of BLs degraded as age group increased. Within the same BL quality, VPR and DR tended to be lower with increased age.Table 1Viable pregnancy rate and delivery rate by blastocyst quality (BL1-6) and age groups (Age1-3)VPRBL-1(a)BL-2BL-3BL-4BL-5BL-6Age1 (22-33)67.0 (175/261)63.6 (56/88)45.0 (27/60)52.3 (34/65)38.1 (24/63)17.4 (4/23)Age2 (34-37)57.3 (122/213)52.8 (47/89)46.7 (28/60)41.5 (34/82)33.8 (22/65)18.5 (5/27)Age3 (38-45)43.0 (40/93)23.5 (16/68)36.8 (21/57)23.8 (19/80)17.5 (10/57)2.7 (1/37)DR (b)Age1 (22-33)59.9 (148/247)50.6 (40/79)33.9 (20/59)41.9 (26/62)29.5 (18/61)4.5 (1/22)Age2 (34-37)47.8 (96/201)41.0 (34/83)43.1 (25/58)29.5 (23/78)26.6 (17/64)11.1 (3/27)Age3 (38-45)32.6 (29/89)17.2 (11/64)29.8 (17/57)20.0 (16/80)12.3 (7/57)2.7 (1/37)a; BL-1 (G6, G5, and G4AA, 4AB, 4BA by Gardner system), BL-2 (G4 except AA, AB, BA), BL-3 (G3AA, 3AB, 3BA), BL-4 (G3 except AA, AB, BA), BL-5 (G2), and BL-6 (G1). b; Among 685 viable pregnancy cycles, the delivery of 63 cycles could not be confirmed, thus we excluded these cases for calculating the delivery rate. Open table in a new tab a; BL-1 (G6, G5, and G4AA, 4AB, 4BA by Gardner system), BL-2 (G4 except AA, AB, BA), BL-3 (G3AA, 3AB, 3BA), BL-4 (G3 except AA, AB, BA), BL-5 (G2), and BL-6 (G1). b; Among 685 viable pregnancy cycles, the delivery of 63 cycles could not be confirmed, thus we excluded these cases for calculating the delivery rate. CONCLUSION: There was a significant correlation between BL quality and both VPR and DR in addition to the influence of age. The findings may help predict successful pregnancy in single BL transfer.

Prediction of pregnancy rate by blastocyst morphological score and age, based on 1,488 single frozen-thawed blastocyst transfer cycles

To present an estimation of the pregnancy rate after IVF or intracytoplasmic sperm injection stratified by blastocyst morphology and age. Retrospective analysis. Private IVF clinic. A total of 1,488 single frozen-thawed blastocyst transfer cycles. All frozen-thawed blastocysts used in the study were obtained in the patients' first oocytes retrieval cycles. Clinical pregnancy rate (CPR), viable pregnancy rate (VPR), and delivery rate (DR) according to blastocyst morphological score (Gardner and Schoolcraft score) in three different age groups: women aged 22-33 years, 34-37 years, and 38-45 years. The quality of blastocysts degraded as age group increased. The proportions of good-quality blastocysts (grades 4 and above) were 62.3%, 56.3%, and 41.1% in age groups of 22-33 years, 34-37 years, and 38-45 years. Within the same blastocyst quality, CPR, VPR, and DR tended to be lower with increased age. Chances of pregnancy were reduced by 60% or more for women 38 years and older with blastocyst morphology of grades 1 and 2. Significant trends were observed for both age and blastocyst morphology groups. There was a significant correlation between blastocyst quality and CPR, VPR, and DR in addition to the influence of age on the three rates. The findings may help predict successful pregnancy in single-blastocyst transfer.