Lisbet Van Landuyt

Intracytoplasmic sperm injection versus in vitro fertilization: A randomized controlled trial and a meta-analysis of the literature

OBJECTIVE To compare ICSI with IVF using two insemination concentrations in moderate male infertility and to compare these data with other randomized controlled trials (RCTs). DESIGN Prospective, randomized, controlled trial and meta-analysis. SETTING University-based tertiary referral center. PATIENT(S) Seventy-three couples undergoing ART. INTERVENTION(S) In one IVF group a standard insemination concentration of 0.2 x 10(6)/mL was used, whereas in the other group a high insemination concentration (HIC) of 0.8 x 10(6)/mL was used. Each protocol was compared with ICSI on sibling oocytes. MAIN OUTCOME MEASURE(S) Fertilization, fertilization failure, and embryonic development. RESULT(S) The overall fertilization rate was significantly lower after standard IVF than after ICSI: 37.4% vs. 64.3%. Where HIC IVF was used, the overall fertilization rate was not significantly different from that after ICSI: 59.6% vs. 67.6%. Eight randomized controlled trials were selected and reviewed together with the present randomized controlled trial by meta-analysis. The risk ratio for an oocyte to become fertilized was 1.9 (95% confidence interval of 1.4 to 2.5) in favor of ICSI, and 3.1 ICSI cycles may be needed to avoid one complete fertilization failure after conventional IVF (95% CI of 1.7 to 12.4). CONCLUSION(S) The data from this study and the meta-analysis show that ICSI is a more efficient technique in terms of fertilization, but not in comparison with HIC IVF.

Developmental stage on day-5 and fragmentation rate on day-3 can influence the implantation potential of top-quality blastocysts in IVF cycles with single embryo transfer

BackgroundIn IVF-ICSI cycles with single embryo transfer (SET), embryo selection for transfer is of crucial importance. The present study aimed to define which embryo parameters might be related to the implantation potential of advanced blastocysts.MethodsOverall, in 203 cycles with SET, developmental characteristics of 93 implanted (group A) and 110 non-implanted (group B) advanced blastocysts of good quality were compared. The following developmental parameters were assessed in the two groups: normal fertilization, developmental stage on day 5, number of blastomeres on day 2 and on day 3, fragmentation rate on day 3, compaction on day 4 and cleavage pattern on day 2 and day 3.ResultsExpanded blastocysts compared to full blastocysts have higher implantation potential (56.5% vs. 29.3%, p < 0.05). In group B, a higher proportion of advanced blastocysts showed between 10% and 50% anucleated fragments on day 3 than in group A (23.6 vs 11.8, P = 0.03). Advanced blastocysts with >10–50% fragments on day 3 showed a significant lower implantation (29.7%) than those with ≤ 10%fragments (49.4%, P = 0.03). All the other parameters analysed were comparable for the two groups.ConclusionDevelopmental stage on day 5 and fragmentation rate on day 3 were related to the implantation potential of advanced blastocysts and should also be taken into account in the selection of the best advanced blastocyst for transfer.

Vitamin D deficiency and pregnancy rates in women undergoing single embryo, blastocyst stage, transfer (SET) for IVF/ICSI

STUDY QUESTION What is the influence of vitamin D deficiency on pregnancy rates among women undergoing IVF/ICSI and Day 5 (blastocyst stage) single embryo transfer (SET)? SUMMARY ANSWER Vitamin D deficiency results in significantly lower pregnancy rates in women undergoing single blastocyst transfer. WHAT IS KNOWN ALREADY Preliminary experiments have identified the presence of vitamin D receptors in the female reproductive system. However, results regarding the effect of vitamin D deficiency on clinical outcomes are conflicting. None of the previous studies adopted a SET strategy. STUDY DESIGN, SIZE, DURATION Serum vitamin D concentration was measured retrospectively in patients who underwent SET on Day 5. Overall 368 consecutive infertile women treated within a period of 15 months were included in the study. PARTICIPANTS/MATERIALS, SETTING, METHODS All patients underwent ovarian stimulation for IVF/ICSI and Day 5 SET. Serum samples were obtained 7 days prior to embryo transfer and stored frozen at -20°C. Samples were collectively analyzed for their 25-OH vitamin D content. Vitamin D deficiency was defined as serum 25-OH vitamin D levels <20 ng/ml in accordance with the Institute of Medicine and the Endocrine Society clinical practice guidelines. MAIN RESULTS AND THE ROLE OF CHANCE Clinical pregnancy rates were significantly lower in women with vitamin D deficiency compared with those with higher vitamin D values (41 versus 54%, P = 0.015).Logistic regression analysis was performed to identify whether vitamin D deficiency is independently associated with clinical pregnancy rates after controlling for 16 potential confounding factors. According to our results vitamin D deficiency was independently associated with lower clinical pregnancy rates, odds ratios [ORs (95% confidence interval (CI) 0.61 (0.39-0.95)] for vitamin D deficiency (deficient versus non-deficient women), P = 0.030. Finally, even when restricting our analysis to women undergoing elective SET (274 patients), vitamin D deficiency was again independently associated with pregnancy rates [OR (95% CI) 0.56 (0.33-0.93), P = 0.024]. LIMITATIONS, REASONS FOR CAUTION Our results refer only to patients undergoing Day 5 SET. Although vitamin D deficiency appears to compromise pregnancy rates in this population, no guidance can be provided regarding a potential relationship between vitamin D deficiency and ovarian reserve or response to ovarian stimulation. WIDER IMPLICATIONS OF THE FINDINGS Vitamin D deficiency impairs pregnancy rates in women undergoing single blastocyst transfer. Future prospective confirmatory studies are needed to validate our results and examine the exact underlying mechanism by which vitamin D levels may impair pregnancy rates in infertile women undergoing IVF/ICSI. STUDY FUNDING/COMPETING INTERESTS None declared.

Pregnancy prediction in single embryo transfer cycles after ICSI using QPCR: validation in oocytes from the same cohort.

Cumulus cell (CC) gene expression is being explored as an additional method to morphological scoring to choose the embryo with the highest chance to pregnancy. In 47 ICSI patients with single embryo transfer (SET), from which individual CC samples had been stored, 12 genes using QPCR were retrospectively analyzed. The CC samples were at the same occasion also used to validate a previously obtained pregnancy prediction model comprising three genes (ephrin-B2 (EFNB2), calcium/calmodulin-dependent protein kinase ID, stanniocalcin 1). Latter validation yielded a correct pregnant/non-pregnant classification in 72% of the samples. Subsequently, 9 new genes were analyzed on the same samples and new prediction models were built. Out of the 12 genes analyzed a combination of the best predictive genes was obtained by stepwise multiple regression. One model retained EFNB2 in combination with glutathione S-transferase alpha 3 and 4, progesterone receptor and glutathione peroxidase 3, resulting in 93% correct predictions when 3 patient and treatment cycle characteristics were included into the model. This large patient group allowed to do an intra-patient analysis for 7 patients, an analysis mimicking the methodology that would ultimately be used in clinical routine. CC related to a SET that did not give pregnancy and CC related to their subsequent frozen/thawed embryos which ended in pregnancy were analyzed. The models obtained in the between-patient analysis were used to rank the oocytes within-patients for their chance to pregnancy and resulted in 86% of correct predictions. In conclusion, prediction models built on selected quantified transcripts in CC might help in the decision making process which is currently only based on subjective embryo morphology scoring. The validity of our current models for routine application still need prospective assessment in a larger and more diverse patient population allowing intra-patient analysis.

Vitamin D deficiency and pregnancy rates following frozen–thawed embryo transfer: a prospective cohort study

STUDY QUESTION What is the effect of vitamin D deficiency on the pregnancy rates following frozen embryo transfer (FET)?. SUMMARY ANSWER Vitamin D deficiency does not affect pregnancy rates in FET cycles. WHAT IS KNOWN ALREADY Although there is evidence that the potential impact of vitamin D deficiency on reproductive outcome may be mediated through a detrimental effect on oocyte or embryo quality, the rationale of our design was based on evidence derived from basic science, suggesting that vitamin D may have a key role in endometrial receptivity and implantation. Only few retrospective clinical studies have been published to date with conflicting results. STUDY DESIGN, SIZE, DURATION This study is the first prospective observational cohort study from the Centre for Reproductive Medicine at the University Hospital of Brussels. The duration of the study was 1 year. PARTICIPANTS/MATERIALS, SETTING, METHODS A total of 280 consecutive patients, who had at least one blastocyst frozen and were planned for a FET, were enrolled in the study following detailed information and signing of a written informed consent. Serum analysis of 25-OH vitamin D was measured on the day of embryo transfer, and the impact of vitamin deficiency was investigated on reproductive outcomes. MAIN RESULTS AND THE ROLE OF CHANCE Among all patients, 45.3% (n = 127) had vitamin D deficiency (<20 ng/ml), and 54.6% (n = 153) had vitamin D levels ≥20 ng/ml. Positive human chorionic gonadotrophin rates were similar among patients with vitamin D deficiency and women with total serum 25-OH vitamin D levels ≥20 ng/ml (40.9 versus 48.3%, P = 0.2). Similarly, no difference was found in clinical pregnancy rates in women with vitamin D deficiency [32.2% (41/127)] compared with those with higher vitamin D levels [37.9% (58/153)]; P = 0.3. When analyzing the results according to different thresholds, as proposed by the Endocrine Society, clinical pregnancy rates were comparable between vitamin D deficient (<20 ng/ml), vitamin D insufficient (20-30 ng/ml) and vitamin D replete women (≥30 ng/ml) [32.3% (41/127) versus 39.5% (36/91) versus 35.5% (22/62), respectively, P = 0.54]. Multivariate logistic regression analysis showed that vitamin D status is not related to pregnancy outcome. LIMITATIONS, REASONS FOR CAUTION Ethnicity in relation to vitamin D status was not assessed, given that the vast majority of patients included in our study were Caucasian, whereas we did only assess 25-OH vitamin D levels and not bioavailable vitamin D. Furthermore, although we failed to find a difference between vitamin D deficient women and women with vitamin D levels ≥20 ng/ml, we need to underscore that our study was powered to detect a difference of 15% in clinical pregnancy rates. WIDER IMPLICATIONS OF THE FINDINGS Vitamin D deficiency does not significantly impair pregnancy rates among infertile women undergoing frozen-thawed cycles. The measurement of vitamin D levels in this population should not be routinely recommended. STUDY FUNDING/COMPETING INTERESTS No external funding was used for this study. No conflicts of interest are declared.

Should a single blastocyst transfer policy be a clinical decision or should it depend on the embryological evaluation on day 3

BackgroundSingle blastocyst transfer has the advantage of maximizing the fresh single pregnancy rate. However, in patients with a low number of good quality embryos on day 3, it remains unclear whether immediate embryo transfer or further embryo culture with blastocyst transfer is the most preferable option.MethodsA retrospective cohort study was carried out in which the outcome of 590 fresh in vitro fertilization (IVF) cycles over a 15 months period and their cryo cycles were analyzed. A total of 341 patients cycles had an elective day 5 strategy independent of intermediate embryo evaluation while another 249 patients underwent a day 5 embryo transfer only if at least four embryos were available on day 3. Blastocyst vitrification was performed using a closed high security system.ResultsDemographics, stimulation parameters and embryological data were comparable in the two groups. Patients in the elective day 5 group had a lower fresh transfer rate (90.62% vs. 95.18%, p < 0.05) as compared to patients with a day 3 or day 5 embryo transfer policy. No difference was observed in the fresh live birth rate and multiple pregnancy rate per initiated cycle (32.84% vs. 28.92%; 1.17% vs 0%) The projected cumulative ongoing pregnancy rate compensating for double counting in case subjects have more than one pregnancy is not different (42.58% vs. 39.84%).ConclusionsDespite lower fresh transfer rates, elective single blastocyst transfer yields a similar projected cumulative ongoing pregnancy rate as in a policy with cleavage stage or blastocyst transfer depending on a good quality embryo count on day 3.

Birthweight of singletons born after cleavage-stage or blastocyst transfer in fresh and warming cycles

STUDY QUESTION Does extended culture to the blastocyst stage affect singleton birthweight after either fresh or vitrified-warmed embryo transfer? SUMMARY ANSWER Singleton birthweight z-scores did not vary significantly after a fresh blastocyst transfer, whereas the additional effect of vitrification remains inconclusive. WHAT IS KNOWN ALREADY Observational studies have associated extended culture with an increased risk of preterm birth and low birthweight. On the contrary, in terms of birthweight and gestational age, singletons born after vitrification have been associated with a better perinatal outcome when compared to those born following a fresh transfer. STUDY DESIGN, SIZE, DURATION Our post-hoc cohort analysis on neonatal outcomes included 447 liveborn singletons was derived from a recent retrospective analysis on cumulative live birth rates after cleavage-stage and blastocyst transfers. These babies were born following a fresh single cleavage-stage transfer (FCT Day 3, n = 113), fresh single blastocyst transfer (FBT Day 5, n = 218), vitrified-warmed cleavage-stage transfer (VCT Day 3, n = 58) or vitrified-warmed blastocyst transfer (VBT Day 5, n = 58). PARTICIPANTS/MATERIALS, SETTING, METHODS Singleton birthweight was the primary outcome measure. Gestational age and gender of the newborn were accounted for by using birthweight z-scores in a multivariable linear regression analysis, adjusting for other confounders (maternal age, BMI, parity and smoking behaviour). Vanishing twins were excluded from the analysis. MAIN RESULTS AND THE ROLE OF CHANCE A significantly lower z-score was observed after blastocyst transfer compared to cleavage-stage transfer in the vitrified-warmed Day 5 group (P = 0.013), a difference not observed in the fresh transfer groups (P = 0.32). Following multivariable regression analysis [adjusted regression coefficient (95% confidence interval)], the FCT and FBT groups showed no significant influence on the birthweight z-scores after fresh transfer [-0.19 (-0.44; 0.05)], but the transfer of vitrified blastocysts (VBT) was associated with a lower birthweight [-0.52 (-0.90; -0.15)] compared with the transfer of vitrified cleavage-stage embryos (VCT). LIMITATIONS, REASONS FOR CAUTION The present cohort was relatively small, especially in the vitrified-warmed subgroups. Pregnancy-associated factors possibly influencing birthweight (such as diabetes, hypertension, pre-eclampsia) were also not accounted for in the analysis. WIDER IMPLICATIONS OF THE FINDINGS Different ART procedures, including extended culture and vitrification, may hold potential safety issues. These results require further confirmation in future larger studies. STUDY FUNDING/COMPETING INTEREST(S) None. TRIAL REGISTRATION NUMBER N/A.