Attitude of dental students toward evidence-based dentistry in Iran: A systematic review.

Background: Dentistry practice has become more complex and challenging in the recent years. The clinical decision-making process has experienced many problems due to changing socioeconomic patterns, knowledgeable patients, rapid technological advances, and information explosion. The present study reviewed the status of the attitude toward evidence-based dentistry (EBD) among dental students of Iran Universities. The effect of the educational intervention was also assessed. Materials and Methods: This systematic review was conducted according to the Preferred Reporting Items for Systematic review and Meta-Analysis checklist. Search strategy was developed by Medical Subject Headings terms and keywords surfing electronic available databases including Medline/PubMed and Google Scholar and local databases such as Scientific Information Database (SID) and Magiran. Two reviewers read the abstracts of all eligible papers and excluded the duplicates. They extracted the information of the full-text of the studies included in the review and assessed the quality by Joanna Briggs Institute critical appraisal checklist. Results: Ten studies including 8 cross-sectional and 2 interventional studies met the criteria. The assessment of the attitude of 937 dental students from a different region of the country toward EBD showed moderate to acceptable status using 3 different tools. In regard to educational interventions, 2 studies were successful to improve their attitude. Conclusion: Although the researchers presented good scores on the attitude questionnaires, the quality of the study tools, the eligible criteria for recruiting the participants and the method of evaluating the construct of attitude should be investigated in future studies.

Effects of parity on preterm delivery in twin gestations conceived with in vitro fertilization.

Objective: To determine the relationship between prior obstetrical history and gestational age at delivery in a twin pregnancy. Design: Retrospective cohort study using the United States Society for Assisted Reproductive Technology Clinic Outcomes Reporting System database. Setting: Clinic-based data. Patients: Patients undergoing in vitro fertilization (IVF) in the United States with live delivery of twins. Interventions: None. Main outcome measures: The main outcome measures are median gestational age at delivery and rate of preterm delivery (before 37 weeks). Results: The median gestational age at delivery of IVF-conceived twins was 36.3 (interquartile rate 34.4, 37.6) weeks for nulliparous women, 35.9 (34.0, 37.1) weeks for parous women with a prior preterm birth, and 36.7 (35.1, 37.7) weeks for parous women without a prior preterm birth. The rate of preterm delivery was 61% for nulliparous women, 70% for parous women with a prior preterm birth, and 55% for parous women without a prior preterm birth. Conclusions: Parous women without a history of preterm delivery had lower rates of preterm delivery in a subsequent twin pregnancy than nulliparous women. Nulliparous women had lower rates of preterm delivery compared with parous women with a history of preterm delivery.

Embryo morphology and live birth in the United States.

Objective: To determine the best-fit live birth rate per embryo based on maternal age, embryo stage, and embryo morphology. Design: Retrospective data analysis. Setting: Fertility clinics. Patients: The patients included were treated with in vitro fertilization in the United States at clinics reporting data to the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System. We analyzed live birth data of unbiopsied autologous cleavage and blastocyst stage embryos for cycles started from 2016 through 2018. The analysis included 223,377 embryo transfers with a total of 336,888 embryos. Interventions: None. Main Outcome Measures: Live birth rate per embryo and rate of multiple gestations per pregnancy. Results: At the mean maternal age of 34 years, fresh embryos produced live birth rates of 19%, 38%, 26%, and 27% for embryos aged 3, 5, 6, and 7 days, respectively. At the age 34 years, live birth rates for day 5 fresh embryos by overall morphology grade were 43% for good, 30% for fair, and 21% for poor. For the transfer of 2 fresh day 5 blastocysts, the rate of multiple gestations per pregnancy was 47% at 25 years old, 44% at 30 years old, 35% at 35 years old, and 23% at 40 years old. Conclusions: The analysis of pregnancy data in the Society for Assisted Reproductive Technology database can be used to calculate live birth rates per embryo based on maternal age, embryo age, and morphology. This information can be used for evidence-based decision making, quality control, and planning multicenter studies.

Effect of trophectoderm biopsy for PGT-A on live birth rate per embryo in good prognosis patients.

PURPOSE: To determine if blastocyst trophectoderm biopsy for PGT-A is associated with an increased rate of live birth per embryo in good prognosis IVF patients at a single center. METHODS: We performed a retrospective cohort study of good prognosis embryo transfer cycles at a single center from 1/1/2017 to 12/31/2019. We evaluated the rate of live birth per embryo with and without PGT-A for transfer of embryos in two groups of good prognosis patients: embryos from donor oocytes and embryos from autologous oocytes with maternal age less than 35 years at oocyte retrieval. Two-sided Fisher's exact tests were used for comparisons between groups. RESULTS: After transfer of embryos created from donor oocytes the live birth rate per euploid embryo was 70.6% (24/34) compared to 34.3% (35/102) for untested embryos for a rate difference of 36.3% (95% CI 18.4-54.1%, p < 0.01). After transfer of embryos created from autologous oocytes with maternal age less than 35 years at oocyte retrieval the live birth rate per euploid embryo was 70.0% (49/70) compared to 52.5% (53/101) for untested embryos for a rate difference of 17.5% (95% CI 3.0-32.0%, p = 0.03). CONCLUSIONS: In good prognosis patients at our center the live birth rate per euploid blastocyst was higher than for untested blastocysts.

Biosorption of cationic Hg2+ and Remazol brilliant blue anionic dye from binary solution using Gelidium corneum biomass.

Remazol brilliant blue (RBB) is an anthraquinone anionic dye that has several commercial uses, especially in the textile industries and is well-known for its detrimental impacts on marine life and the surrounding ecosystem. Mercury (Hg2+) is also one of the most severe hazardous environmental contaminants due to its bioaccumulation through the food chain and high toxicity to the human embryo and fetus. The biosorption potential of Gelidium corneum biomass for bioremoval of Hg2+ and RBB dye simultaneously from binary mixture was assessed. The effects of initial pH, contact time, Hg2+, RBB, and biomass concentrations on the biosorption process were investigated in 50 batch experiments using a Face-centered central composite design. The maximum removal percentage of Hg2+ (98.25%) was achieved in the run no. 14, under optimum experimental conditions: 200 mg/L Hg2+, 75 mg/L RBB, pH 5. At 30 °C, 4 g/L algal biomass was used, with a contact time of 180 min. Whereas, the maximum removal percentage of RBB (89.18%) was obtained in the run no. 49 using 200 mg/L Hg2+, 100 mg/L RBB, pH 5, 4 g/L algal biomass and 180 min of contact time. FTIR analysis of Gelidium corneum biomass surface demonstrated the presence of many functional groups that are important binding sites responsible for Hg2+ and RBB biosorption. SEM analysis showed apparent morphological alterations including surface shrinkage and the appearance of new shiny adsorbate ion particles on the Gelidium corneum biomass surface after the biosorption process. The EDX study reveals an additional optical absorption peak for Hg2+, confirming the role of Gelidium corneum biomass in Hg2+ biosorption. In conclusion, Gelidium corneum biomass has been shown to be an eco-friendly, sustainable, promising, cost-effective and biodegradable biosorbent to simultaneously biosorb Hg2+ and RBB dye from aquatic ecosystems.

Effect of age and morphology on sustained implantation rate after euploid blastocyst transfer.

RESEARCH QUESTION: What impact does maternal age and embryo morphology have on sustained implantation rates of euploid blastocysts? DESIGN: This was a retrospective analysis of sustained implantation rates of euploid blastocysts stratified by maternal age and morphology. The primary analysis included 208 embryo transfers with a total of 229 embryos transferred from January 2017 through August 2020. RESULTS: For all ages the sustained implantation rates for day 5 good quality blastocysts were higher than for day 5 fair, day 5 poor and day 6 blastocysts. At a maternal age of 36 years the best-fit sustained implantation rates were 86% for day 5 good quality blastocysts, 64% for day 5 fair, 63% for day 5 poor, and 51% for all day 6 blastocysts analysed as one group. When controlling for morphology and day of biopsy, there were higher sustained implantation rates for euploid embryos of younger patients compared with older patients. The best-fit sustained implantation rates for age 33 compared to age 39 years were 86% versus 80% for day 5 good, 71% versus 62% for day 5 fair, 59% versus 55% for day 5 poor, and 81% versus 46% for all day 6. CONCLUSIONS: There was a clinically significant higher sustained implantation rate at all ages for euploid day 5 good quality embryos compared with day 5 fair, day 5 poor and day 6 embryos.

Developmental potential of immature human oocytes aspirated after controlled ovarian stimulation.

PURPOSE: Intracytoplasmic sperm injection (ICSI) for initially immature oocytes that mature in vitro is controversial and practice varies widely. While it may increase the number of usable embryos, it may also be time-intensive and potentially low-yield. This study sought to elucidate which patients may benefit from ICSI of initially immature oocytes that matured in vitro. METHODS: A retrospective study comparing fertilization, cleavage, blastulation, and embryo usage rates between sibling initially immature and mature oocytes that underwent ICSI between 2015 and 2019 was performed. Outcomes of initially immature oocytes were stratified by initial maturation stage, timing of progression to metaphase II (MII) in vitro, percentage of mature oocytes in the cycle, and female age. RESULTS: Ten thousand eight hundred seventeen oocytes from 889 cycles were included. Of 3137 (29.0%) initially immature oocytes, 418 (13.3%) reached MII later on the day of retrieval (day 0) and 1493 (47.6%) on day 1. Overall, embryos originating from initially immature oocytes had lower cleavage and blastulation rates compared to those from initially mature oocytes (P<0.05, all groups). However, embryos from oocytes that matured later on day 0 comprised a unique subset that had clinically similar cleavage (75% vs 80%, RR 0.93, P=0.047) and blastulation rates (41% vs 50%, RR 0.81, P=0.024) compared to initially mature oocytes. Women with low percentages of mature oocytes in the cycle overall and women ≥40 in cleavage cycles derived the highest relative benefit from the use of immature oocytes. CONCLUSION: ICSI of immature oocytes, particularly those that mature later on the day of retrieval, may improve numbers of usable embryos. This study supports routine reassessment of immature oocytes for progression to MII and ICSI on day 0. An additional reassessment on day 1 may also be of use in older women or those with low percentage of mature oocytes.

What is the optimal timing of intracytoplasmic sperm injection (ICSI) after EGG retrieval? A randomized controlled trial.

PURPOSE: To determine if oocyte denudation and ICSI at 36.5 versus 39 h post HCG and/or Lupron trigger (2.5 h versus 5 h post-oocyte retrieval) influences fertilization and blastulation rates in good prognosis couples METHODS: We performed a prospective, randomized controlled trial of 12 patients undergoing IVF with ICSI at an academic fertility center, resulting in 206 MII oocytes analyzed. At time of retrieval, patients with more than 10 oocytes retrieved had their oocytes randomized into two groups-one group for oocyte denudation and ICSI at 36.5 h post HCG and/or Lupron trigger and the other group for these procedures at 39 h post HCG and/or Lupron trigger (2.5 and 5 h after oocyte retrieval). Primary outcomes were fertilization and blastulation rates. RESULTS: No difference was observed in fertilization rate, total blastulation rate, or day of blastulation based on timing of denudation and ICSI (all p > 0.05). Multiple regression analyses for fertilization and blastulation controlling for age and BMI revealed no difference in fertilization based on time of ICSI (p = 0.38, 0.71, respectively). A conditional logistic regression to account for multiple oocytes derived from each patient also found no difference in fertilization or blastulation based on timing of ICSI, even when controlling for age and BMI (p = 0.47, 0.59, respectively). CONCLUSION(S): In good prognosis couples, we observed no difference in fertilization or blastulation rates based on timing of ICSI within the currently accepted 2- to 6-h window post-retrieval based on a 34-h trigger. The oocyte appears to have a physiological tolerance for fertilization during this window of time, and variability in the timing of ICSI during this window is unlikely to have an impact on cycle outcome.

A validated model for predicting live birth after embryo transfer.

Accurately predicting the probability of live birth and multiple gestations is important for determining a safe number of embryos to transfer after in vitro fertilization. We developed a model that can be fit to individual clinic data for predicting singleton, twin, and total live birth rates after human embryo transfer. The predicted and observed rates of singleton and twin deliveries were compared in a tenfold cross-validation study using data from a single clinic. The model presented accounts for patient age, embryo stage (cleavage or blastocyst), type of transfer cycle (fresh or frozen) and uterine/universal factors. The standardized errors for rates of singleton and twin deliveries were normally distributed and the mean errors were not significantly different from zero (all p > 0.05). The live birth rates per embryo varied from as high as 43% for fresh blastocysts in the 35-year-old age group to as low as 1% for frozen cleavage stage embryos in the 43-year-old age group. This quantitative model or a simplified version can be used for clinics to generate and analyze their own data to guide the number of embryos to transfer to limit the risk of multiple gestations.

Influence of Trophectoderm Biopsy Prior to Frozen Blastocyst Transfer on Obstetrical Outcomes.

The purpose of this study is to determine if trophectoderm biopsy prior to autologous frozen blastocyst transfer in programmed cycles is associated with gestational age at delivery, birth weight, or cesarean rate in viable singleton gestations. We conducted a retrospective cohort study of patients at a university-affiliated center that had viable singleton gestations after autologous frozen blastocyst transfer in programmed cycles. Obstetrical outcomes of 67 pregnancies after blastocyst trophectoderm biopsy for preimplantation genetic testing were compared to 78 pregnancies from unbiopsied blastocysts. There were no significant differences between the two cohorts in terms of maternal age, BMI, or ethnicity. There were no differences in the preimplantation genetic testing cohort compared to the reference cohort for median gestational age at delivery (39.4 vs 39.4 weeks, p = 0.80), median birth weight (3420 vs 3430 g, p = 0.97), cesarean rate (51% vs 44%, p = 0.41), preterm delivery rate (12% vs 8%, p = 0.41), rate of low birth weight (12% vs 9%, p = 0.59), or rate of birth weight over 4000 g (13% vs 8%, p = 0.29). There were no differences in the primary outcomes with subgroup analysis based on fetal sex, single embryo transfer, gravidity, history of prior term birth, and maternal age < or ≥ 35 years. Trophectoderm biopsy prior to frozen blastocyst transfer in programmed cycles was not associated with adverse obstetrical outcomes related to gestational age at delivery, birth weight, or cesarean rate.

Design and validation of a model for quality control monitoring of dichotomous in vitro fertilization outcomes.

OBJECTIVE: To develop and validate a practical model for quality control monitoring of dichotomous in vitro fertilization (IVF) outcomes such as pregnancy resulting from the transfer of euploid blastocysts. DESIGN: We designed and validated a model for quality control monitoring of dichotomous IVF outcomes. We demonstrate use of this model for assessment of euploid blastocyst transfer quality control based on fetal heartbeat rate per embryo. The model uses 3 weighted moving averages with window sizes of 21, 51, and 101 embryo transfers to detect short and long-term shifts in success rates. The quality warning limit was set to have a 2-sided type I error rate of 0.30 per 100 embryo transfers and the control limit was set to have a type I error rate of 0.05 per 100 embryo transfers. Simulation studies were performed to validate the model through assessment of type I and type II errors using custom computer programs. SETTING: Not applicable. PATIENT(S): Patients undergoing IVF. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Type I and type II error rates and statistical power analysis. RESULT(S): Validated quality warning and control limits are presented for a range of expected outcome rates. The power to detect a 20% decrease from an expected fetal heartbeat rate of 50%, when the decrease persisted for 50 embryo transfers, was 86% for the warning limit and 57% for the control limit. CONCLUSION(S): This model can be used for continuous quality control assessment of dichotomous IVF outcomes such as pregnancy rates.

Transfer the best and biopsy the rest? Blastocyst euploidy rates differ by morphology and day of biopsy.

PURPOSE: To determine if blastocyst euploidy rates differ by embryo morphology or day of biopsy. METHODS: We performed a retrospective analysis of euploidy rates based on patient age, overall embryo morphology grade (good, fair, or poor), and day of biopsy (days 5, 6, or 7) for blastocysts undergoing preimplantation genetic testing for aneuploidy (PGT-A). Our primary analysis included 904 embryos from oocytes age 33-39 years at retrieval. RESULTS: In our primary analysis, euploidy rates were higher for good quality embryos than poor (64% vs. 48%, p < 0.01) and for fair quality embryos than poor (61% vs. 48%, p < 0.01). There was no significant difference in the euploidy rate between good and fair quality embryos (64% vs. 61%, p = 0.56). Embryos biopsied on day 5 were more likely to be euploid than embryos biopsied on day 6 (59% vs. 50%, p < 0.01) or day 7 (59% vs. 37%, p < 0.01). There was no significant difference in the euploidy rate between day 6 and day 7 embryos (50% vs. 37%, p = 0.07). CONCLUSION: PGT-A may be more useful in cycles where a lower euploidy rate is expected based on age at oocyte retrieval, embryo morphology, and day of biopsy. There may be little benefit to biopsy of embryos with a high euploidy rate. Young patients with one or more good quality day 5 embryos may benefit from a "transfer the best fresh and biopsy the rest" strategy.

Effect of Age and Morphology on Live Birth Rate After Cleavage Stage Embryo Transfer.

Accurate knowledge of the live birth rate for cleavage stage embryos is essential to determine an appropriate number of embryos to transfer at once. Results from previous studies lack details needed for practical use. This is a mathematical analysis and model building study of day 3 cleavage stage embryo transfers. A total of 996 embryos were transferred in 274 fresh and 83 frozen embryo transfers. Embryo morphology was divided into 4 groups based on number of cells and fragmentation percentage. Each embryo transfer was modeled as an equation equating the sum of the live birth rates of the transferred embryos to the number of live births that resulted. The least squares solution to the system of embryo transfer equations was determined using linear algebra. This analysis was repeated for ages 35 to 42 years old at oocyte retrieval. The best fit live birth rates per embryo in the age group centered on 35 years old were 29%, 13%, 10%, and 9% for embryos in the 8-cell with ≤ 5% fragmentation, 8-cell with > 5% fragmentation, 9-12 cell, and 6-7 cell groups, respectively. Cleavage stage embryos with fewer than 6 cells on day 3 had very low best fit live birth rates close to 0% at age 39 years and were excluded from the primary analysis to prevent overfitting. These live birth rates can be used with a simple embryo transfer model to predict rates of single and multiple gestation prior to a planned cleavage stage embryo transfer.

Micro-RNAs involved in cellular proliferation have altered expression profiles in granulosa of young women with diminished ovarian reserve.

PURPOSE: The study aims to determine differences in micro-RNA (miRNA) expression in granulosa (GC) and cumulus cells (CC) between young women with diminished ovarian reserve (DOR) or normal ovarian reserve (NOR). Secondary objective was to identify downstream signaling pathways that could ultimately indicate causes of lower developmental competence of oocytes from young women with DOR. METHODS: The method of the study is prospective cohort study. RESULTS: Of the miRNA, 125 are differentially expressed in GC between DOR and NOR. Only nine miRNA were different in CC; therefore, we focused analysis on GC. In DOR GC, miR-100-5p, miR-16-5p, miR-30a-3p, and miR-193a-3p were significantly downregulated, while miR-155-5p, miR-192-5p, miR-128-3p, miR-486-5p, miR130a-3p, miR-92a-3p, miR-17-3p, miR-221-3p, and miR-175p were increased. This pattern predicted higher cell proliferation in the DOR GC. The primary pathways include MAPK, Wnt, and TGFbeta. CONCLUSIONS: The miRNA pattern identified critical functions in cell proliferation and survival associated with DOR. GC in women with DOR seems to respond differently to the LH surge.

Pushing the limits of detection: investigation of cell-free DNA for aneuploidy screening in embryos.

OBJECTIVE: To determine the accuracy of cell-free DNA (cfDNA) in spent embryo medium (SEM) for ploidy and sex detection at the cleavage and blastocyst stages. To determine if assisted hatching (AH) and morphologic grade influence cfDNA concentration and accuracy. DESIGN: Prospective cohort. SETTING: Academic fertility center. PATIENT(S): Nine patients undergoing IVF; 41 donated two-pronuclei embryos and 20 embryos from patients undergoing preimplantation genetic testing for aneuploidy (PGT-A). INTERVENTIONS(S): In a donated embryo arm, SEM was collected on days 3 and 5, with one-half of the embryos undergoing AH before and one-half after. In a clinical arm, SEM was collected on day 5 before trophectoderm (TE) biopsy. Samples underwent PGT-A with the use of next-generation sequencing. cfDNA results were compared with corresponding whole embryos and TE biopsies. MAIN OUTCOME MEASURE(S): Concordance rates, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for ploidy and sex detection with the use of cfDNA. RESULT(S): Of 141 samples, cfDNA was amplified in 39% and 80.4% of days 3 and 5 SEM, respectively. Concordances for ploidy and sex, respectively, were 56.3% and 81.3% between day 3 cfDNA and whole embryos, and 65% and 70% between day 5 cfDNA and TE biopsies. Day 5 cfDNA sensitivity and specificity for aneuploidy were 0.8 and 0.61, respectively. PPV and NPV were 0.47 and 0.88, respectively. Timing of AH and morphology did not influence cfDNA concentration or accuracy. CONCLUSION(S): cfDNA is detectable on days 3 and 5, but more accurate on day 5. Although our data suggest moderate concordance rates, PGT-A with the use of cfDNA must be further optimized before clinical implementation.

Blastulation timing is associated with differential mitochondrial content in euploid embryos.

PURPOSE: Preimplantation genetic screening (PGS) and assessment of mitochondrial content (MC) are current methods for selection of the best embryos for transfer. Studies suggest that time-lapse morphokinetics (TLM) may also be helpful for selecting embryos more likely to implant. In our study, we sought to examine the relationship between TLM parameters and MC to determine if they could be used adjunctively in embryo selection. We also examined the relationship between MC with ploidy and blastulation. METHODS: Cryopreserved human embryos at the zygote stage were thawed and cultured in a time-lapse system. Blastomere and trophectoderm biopsies were performed on days 3 and 6. Biopsied cells and all whole embryos from day 6 were analyzed for MC (ratio of mitochondrial to nuclear DNA) and ploidy using next-generation sequencing. RESULTS: In embryos, MC per cell declined between day 3 and day 6. While early cleavage parameters did not predict MC, embryos with longer blastulation timing had higher MC on day 6. Day 6 MC was lower in euploid vs. aneuploid embryos and lower in blastocysts vs. arrested embryos. CONCLUSIONS: A lower MC at the blastocyst stage was associated with euploid status and blastocyst formation, indicating better embryo quality compared to those with a higher MC. Higher MC in aneuploid and arrested embryos may be explained by slower cell division or degradation of genomic DNA over time. Blastulation timing may be helpful for selection of higher quality embryos. Combining blastulation timing and MC along with morphologic grading and euploid status may offer a new direction in embryo selection.

Evaluation of post-thaw DNA integrity of mouse blastocysts after ultrarapid and slow freezing.

OBJECTIVE: To evaluate the effect of vitrification and two other methods of slow cryopreservation on DNA integrity in expanded and nonexpanded blastocysts. DESIGN: Prospective in vitro study. SETTING: Tertiary care academic hospital. INTERVENTION(S): 1) Twenty-two expanded blastocysts (EB) and 17 nonexpanded blastocysts (NEB) vitrified in cryotips; 2) 15 EB and 16 NEB by slow freezing using propanediol; 3) 11 EB and 16 NEB by slow cryopreservation using glycerol; and 4) 14 EB and 13 NEB as fresh control samples. MAIN OUTCOME MEASURE(S): DNA fragmentation by TUNEL and confocal imaging. RESULT(S): Blastocysts slowly cryopreserved with glycerol showed DNA integrity of 94.76 +/- 4.70% and 90.87 +/- 6.16% for NEB and EB, respectively. Propanediol cryopreservation showed values of 72.63 +/- 13.44% and 56.19 +/- 25.49% and vitrification 84.36 +/- 8.7%6 and 77.61 +/- 16.65%, respectively, for the same groups. The NEB showed less DNA fragmentation than EB in all cryopreservation techniques, but this was significant only with slow freezing using propanediol. CONCLUSION(S): All cryopreservation techniques induce DNA damage to blastocysts. Damage is maximal with propanediol and minimal with slow freezing using glycerol. The more expanded the blastocyst, the greater is the susceptibility to DNA damage during cryopreservation.