Relationship between peak serum estradiol levels and treatment outcome in in vitro fertilization cycles after embryo transfer on day 3 or day 5

Evaluation of the relationship between serum estradiol levels on human chorionic gonadotropin administration day and intracytoplasmic sperm injection outcomes: A retrospective population-based study

Background

The correlation between high estradiol (E2) levels induced by controlled ovarian hyperstimulation (COH) and pregnancy is controversial.

Objective

To assess the effect of serum E2 levels on the day of human chorionic gonadotropin administration on the intracytoplasmic sperm injection (ICSI) outcome.

Materials and Methods

The current study included 551 participants who had undergone ICSI between May 2014 and May 2016. Based on E2 levels, the individuals aged < 37 yr (n = 502) and 37-42 yr (n = 49) were categorized into six and three groups, respectively. ICSI outcomes including the number of retrieved oocytes (NRO), number of embryos (NE), pregnancy rate, and abortion rate were analyzed in both groups.

Results

Among participants aged < 37 yr, the NRO and NE were 8.69 ± 3.82 and 5.24 ± 2.32, respectively and they had a significant correlation with the E2 level on human chorionic gonadotropin administration day (p < 0.001 for both). Among participants aged > 37 yr, NRO and NE were 5.18 ± 3.17 and 3.40 ± 2.23, respectively, and the NRO (p < 0.001), NE (p < 0.001), pregnancy rate (p < 0.001), abortion rate (p = 0.007), and the number of grade A and B embryos (p = 0.003) had a significant association with the E2 level.

Conclusion

COH is a costly procedure that may have negative effects on endometrial receptivity. Thus, in order to prevent these effects and also to reduce the costs of COH, we recommend gaining optimum number of oocytes rather than maximum number during the procedure.

Effects of immediate versus delayed frozen embryo transfer in high responder patients undergoing freeze-all cycles

Background

Frozen embryo transfer (FET) can greatly improve the pregnancy outcomes for high responder patients. However, it is not known whether the timing of FET is a risk factor on pregnancy outcomes in high responder patients undergoing freeze-all cycles.

Methods

A retrospective cohort study to compare the pregnancy outcomes of the immediate and delayed FET groups in high responder patients undergoing freeze-all cycles. The two groups were defined as that FET took place either within the first menstrual cycle following oocyte retrieval or afterwards. Propensity score matching was used to make the potential risk factors of the two groups comparable. Multivariable regression analysis was used to study the effect of the timing of FET on pregnancy outcomes in the entire cohort and propensity score-matched cohort, even in different controlled ovarian hyperstimulation protocol cohorts as subgroup analysis.

Results

We obtained 1130 patients in immediate FET group and 998 patients in delayed FET group, and the average age of the two groups were 30.30 and 30.63. We showed that the immediate FET group were equivalent to delayed FET group in the entire cohort [clinical pregnancy rate (CPR), 61.0% versus 63.4%, adjusted odd ratio (OR), 0.939, 95% confidence interval (CI), 0.781–1.129; spontaneous abortion rate (SAR), 10.1% versus 12.6%, adjusted OR, 0.831, 95% Cl (0.628–1.098); live birth rate (LBR), 49.9% versus 49.2%, adjusted OR, 1.056, 95% Cl (0.883–1.263)]. The same results were obtained by χ² test in the propensity score-matched cohort (CPR, 60.5% versus 63.5%; SAR, 11.6% versus 12.3%; LBR, 48% versus 49.3%) (P > 0.05). Subgroup analysis indicated that pregnancy outcomes of immediate FET were no difference to delayed FET in gonadotropin-releasing hormone agonist (GnRH-a) protocol (P > 0.05). The SAR of the immediate FET group were lower than that of the delayed FET group in GnRH antagonist protocol (adjusted OR, 0.645, 95% CI, 0.430–0.966) (P < 0.05), no differences were observed in CPR and LBR (P > 0.05).

Conclusions

The pregnancy outcomes of immediate FET were no difference to delayed FET in high responder population undergoing freeze-all cycles.

Association between serum oestradiol level on the hCG administration day and neonatal birthweight after IVF-ET among 3659 singleton live births

Oestradiol, an important hormone in follicular development and endometrial receptivity, is closely related to clinical outcomes of fresh in vitro fertilization-embryo transfer (IVF-ET) cycles. A supraphysiologic E2 level is inevitable during controlled ovarian hyper-stimulation (COH), and its effect on the outcome of IVF-ET is controversial. The aim of this retrospective study is to evaluate the association between elevated serum oestradiol (E2) levels on the day of human chorionic gonadotrophin (hCG) administration and neonatal birthweight after IVF-ET cycles. The data of 3659 infertile patients with fresh IVF-ET cycles were analysed retrospectively between August 2009 and February 2017 in First Hospital of Zhengzhou University. Patients were categorized by serum E2 levels on the day of hCG administration into six groups: group 1 (serum E₂ levels ≤ 1000 pg/mL, n = 230), group 2 (serum E2 levels between 1001 and 2000 pg/mL, n = 524), group 3 (serum E₂ levels between 2001 and 3000 pg/mL, n = 783), group 4 (serum E₂ levels between 3001 and 4000 pg/mL, n = 721), group 5 (serum E2 levels between 4001 and 5000 pg/mL, n = 548 ), and group 6 (serum E2 levels > 5000 pg/mL, n = 852). Univariate linear regression was used to evaluate the independent correlation between each factor and outcome index. Multiple logistic regression was used to adjust for confounding factors. The LBW rates were as follows: 3.0% (group 1), 2.9% (group 2), 1.9% (group 3), 2.9% (group 4), 2.9% (group 5), and 2.0% (group 6) (P = 0.629), respectively. There were no statistically significant differences in the incidences of neonatal LBW among the six groups. We did not detect an association between peak serum E2 level during ovarian stimulation and neonatal birthweight after IVF-ET. The results of this retrospective cohort study showed that serum E2 peak levels during ovarian stimulation were not associated with birth weight during IVF cycles. In addition, no association was found between higher E2 levels and increased LBW risk. Our observations suggest that the hyper-oestrogenic milieu during COS does not seem to have adverse effects on the birthweight of offspring after IVF. Although this study provides some reference, the obstetric-related factors were not included due to historical reasons. The impact of the high estrogen environment during COS on the birth weight of IVF offspring still needs future research.

Is the probability of pregnancy after ovarian stimulation for IVF associated with serum estradiol levels on the day of triggering final oocyte maturation with hCG? A systematic review and meta-analysis

PURPOSE

The objective of this systematic review and metaanalysis was to examine if the probability of pregnancy after ovarian stimulation for in vitro fertilization (IVF), using GnRH analogues and gonadotrophins is associated with serum estradiol level (Ε₂) on the day of triggering final oocyte maturation with human chorionic gonadotrophin (hCG).

METHODS

Twenty-one studies were eligible for this systematic review, including 19,598 IVF cycles, whereas three studies were eligible for metaanalysis, including 641 IVF cycles. The main outcome measure was achievement of ongoing pregnancy/live birth and, if not available, clinical pregnancy or biochemical pregnancy.

RESULTS

Pooling of data showed no differences in the probability of clinical pregnancy between patients with high and low Ε₂ levels on the day of triggering final oocyte maturation. The pooled effect sizes for the Ε₂ thresholds groups constructed, regarding clinical pregnancy were 2000-3000 pg/mL-OR 0.91, 95% CI 0.55 to 1.50, (fair quality/moderate risk of bias, n = 1 study), 3000-4000 pg/mL-OR 0.89, 95% CI 0.46 to 1.70, (fair quality/moderate risk of bias, n = 1 study, good quality/no information on which to base a judgement about risk of bias n = 2 studies), 4000-5000 pg/mL-OR 0.74, 95% CI 0.37 to 1.49 fair quality/moderate risk of bias, n = 1 study), 5000-6000 pg/mL-OR 0.62, 95% CI 0.19 to 1.98, (fair quality/moderate risk of bias, n = 1 study). In addition, no difference was observed in the probability of ongoing pregnancy for the Ε₂ threshold group of 3000-4000 pg/mL OR 0.85, 95% CI 0.40 to 1.81(good quality/no information on which to base a judgement about risk of bias, n = 1 study).

CONCLUSION

Currently, there is insufficient evidence to support or deny the presence of an association between the probability of pregnancy and serum Ε₂ levels on the day of triggering final oocyte maturation with hCG in women undergoing ovarian stimulation for IVF.

In vitro maturation of human immature oocytes for fertility preservation and research material

Aim

In recent years, the importance of fertility preservation (FP) has increased. In vitro maturation (IVM), an important technique in FP, has started to be used in the clinic, but controversies persist regarding this technique. Here, a survey of IVM for FP is provided.

Methods

Based on a literature review, the applications of FP, methods of FP, IVM of oocytes that had been collected in vivo and ex vivo, maturation of oocytes after IVM for FP, cryopreservation of oocytes for FP, explanation of the procedures to patients, and recent research on FP using IVM were investigated.

Results

Although IVM for FP remains controversial, the application of FP is expected to expand. Depending on the age and disease status of the patient, various methods of oocyte collection and ovarian stimulation, as well as various needle types and aspiration pressures, have been reported. The maturation rate of IVM in FP ranges widely and requires optimization in the future. In regard to cryopreservation for matured oocytes, the vitrification method is currently recommended.

Conclusion

Regarding FP for patients with cancer, the treatment of cancer is prioritized; thus, the time and use of medicines are often constrained. As several key points regarding IVM remain unclear, well‐designed and specific counseling for patients is necessary.

The decline in serum estradiol on the second day after oocyte retrieval affects the outcome of IVF/ICSI-ET treatment in high ovarian responders

OBJECTIVE

To investigate the predictive value of the decline in serum estradiol on the second day after oocyte retrieval on the outcomes of in vitro fertilization (IVF) or intra-cytoplasmic sperm injection and embryo transfer (ICSI-ET) among high ovarian responders.

DESIGN

Retrospective single-center cohort study.

SETTING

Tertiary-care, university-affiliated teaching hospital. Patients Women aged 20-45 years undergoing assisted reproduction treatment from June 2014 to December 2015.

INTERVENTIONS

A total of 980 cycles were included; 395 high responders (Group 1) and 256 normal responders (Group 3) underwent embryo transfer (ET) in fresh ET cycles. A total of 329 high ovarian responders who underwent cryopreservation of all embryos (Group 2) were recruited as controls. The cases were divided into the following five subgroups according to the rate of serum estradiol decline on the second day after oocyte retrieval: 50.00-59.99% (Subgroup A), 60.00-69.99% (Subgroup B), 70.00-79.99% (Subgroup C), 80.00-89.99% (Subgroup D) and ≥ 90.00% (Subgroup E). The clinical outcomes were analyzed.

MAIN OUTCOME MEASURES

Clinical pregnancy rate, implantation rate.

RESULTS

In Group 1, the pregnancy rate decreased from 51.33 to 36.72% and the implantation rate decreased from 30.93 to 21.70% when the level of serum estradiol on the second day after oocyte retrieval decreased by more than 80%, which was a statistically significant decline (p < 0.05). The peak estradiol (E₂) value and implantation rate were also significantly different (p < 0.05). In Group 2, the decline of serum E₂ on the second day after oocyte retrieval had no significant effect on the clinical pregnancy rate or the implantation rate. The trend was similar in Group 3.

CONCLUSIONS

A decline in the E₂ level of > 80% after oocyte retrieval may play an important role in unsatisfactory IVF/ICSI-ET outcomes among high ovarian responders.

Effect of elevated estradiol levels on the hCG administration day on IVF pregnancy and birth outcomes in the long GnRH-agonist protocol: analysis of 3393 cycles

INTRODUCTION

This retrospective study aimed to evaluate the association between elevated serum estradiol (E ₂) levels on the human chorionic gonadotrophin (hCG) administration day and in vitro fertilization (IVF) pregnancy and birth outcomes in the long GnRH-agonist protocol.

METHODS

This study analyzed the data of 3393 infertile women who underwent initial fresh IVF. The patients were categorized into high and low E ₂ groups based on their serum E ₂ levels on the hCG day. Pregnancy and birth outcomes were compared.

RESULTS

The implantation rate, clinical pregnancy rate, and live birth rate were all significantly higher in the high E ₂ group than in the low E ₂ group (p < 0.05). The good-quality embryo rate and abortion rate did not significantly differ between the two groups. There were no significant differences in the mode of delivery, gestational age, birth weight, and fetal gender between the two groups. Furthermore, there were no differences in the risk of preterm birth, low birth weight, and fetal malformation between the two groups in 860 single live births. Subgroup analysis of singleton pregnancies in the high E ₂ (E ₂ ≥ 3757 pg/mL) group revealed a significant increase in abortion rate in the age group of ≥37 years.

CONCLUSIONS

Elevated serum E ₂ levels associated with controlled ovarian stimulation did not increase the risks of preterm birth, low birth weight, and fetal malformation. High E ₂ on the hCG day had no detrimental effect on the implantation rate, clinical pregnancy rate, and live birth rate.

Fertilization rate and its determinants in intracytoplasmic sperm injection

Objective:

To identify predictors of fertilization rate in patients of unexplained infertility after intracytoplasmic sperm injection (ICSI).

Methods:

Retrospective analysis of females (282) enrolled in quasi experimental design for ICSI at “Islamabad Clinic Serving Infertile Couples” was carried out from July 2013 till June 2014. Females with unexplained infertility were included, whereas well defined male and female causes of infertility were excluded. Fertilization rate (FR) was calculated as percentage transformation of micro injected oocytes into two pronuclei. Categorical variable of FR defined on the basis of 50% FR grouped females; Group I with FR ≤50% and Group II with FR >50%. The groups were compared in terms of demographic variables, base line hormones and oocyte parameters. Univariate logistic regression was executed to obtain odds ratio with 95% confidence interval to quantify the association of predictors like age, duration of infertility, oocytes parameters, hormones; Estradiol, progesterone, follicle stimulating hormone (FSH), luteinizing hormone, prolactin and cytokines interleukin-Iβ (IL-Iβ) with the FR.

Results:

In our study out of 282 females, 19 (6.73%) were in group I and 263 (93.26%) comprised of Group II. Females with high FR(group II) had low Progesterone and FSH (p=0.04, p=0.02) respectively. Mature oocytes (OR: 0.35; 95% CI 1 – 2.56) and IL-Iβ in follicular phase (OR: 1.04; 95% CI: 0.000- 1.20) were significant positive predictors of FR while peak progesterone and FSH had significant negative effect on it

Conclusion:

Fertilization of oocytes in females of unexplained infertility depended on maturity of oocytes and optimal amounts of ILI- β released by developing follicles in the follicular phase of stimulation cycles of ICSI.

Cited2 protein level in cumulus cells is a biomarker for human embryo quality and pregnancy outcome in one in vitro fertilization cycle

OBJECTIVE

To determine whether the levels of CBP/p300 interacting transactivator with ED-rich tail 2 (Cited2) protein in cumulus cells (CCs) derived from patients undergoing IVF related to infertility factors, embryo quality, and clinical outcomes in one IVF cycle.

DESIGN

Retrospective analysis of human CCs.

SETTING

Public hospital and university.

PATIENT(S)

A total of 103 (conventional) IVF patients and 32 intracytoplasmic sperm injection patients.

INTERVENTION(S)

All CCs from each patient's oocytes were considered as one sample. The patients were divided into two groups according to whether the Cited2/β-actin levels in their CCs were above or below the mean level detected for all patients.

MAIN OUTCOME MEASURE(S)

Embryo quality and clinical outcomes of IVF patients.

RESULT(S)

The oocytes derived from the group of patients whose CCs showed lower Cited2 levels displayed higher fertilization, transferable embryo, and implantation rates. Moreover, the patients in this group were more likely to have a successful pregnancy outcome. Among different infertility factors, a total of 78.6% of patients with polycystic ovary syndrome had a higher Cited2 level in CCs. Additionally, patients with a lower basal FSH level belonged to the higher Cited2 levels group. The expression of two genes (phosphoenolpyruvate carboxykinase 1 [PCK1] and progesterone receptor [PR]) and the glucose content in CCs were also markedly increased in CCs derived from patients with higher Cited2 levels.

CONCLUSION(S)

The present findings imply that Cited2 level in CCs is associated with polycystic ovary syndrome, embryo quality, and pregnancy outcome of IVF patients.

Blastocyst-stage versus cleavage-stage embryo transfer in the first frozen cycles of OHSS-risk patients who deferred from fresh embryo transfer

Elective cryopreservation of all embryos has been the most effective means to avoid developing ovarian hyperstimulation syndrome (OHSS). However, it is still unknown which stage is optimal for freezing and transferring into uterus in OHSS-risk patients. This study was undertaken to evaluate whether OHSS-risk patients could benefit from transferring blastocysts. A total of 162 women were allocated to cleavage-stage embryo transfer (ET) (group A = 70) and blastocysts transfer (group B = 92) on the basis of patients' voluntary in their first frozen cycles. Although the mean number of transferred embryos in group A was significantly more than those in group B (2.37 ± 0.52 versus 2.11 ± 0.52, p < 0.05), the clinical pregnancy rates, implantation rates and live birth rates in group B were significantly higher than those in group A (47.83% versus 31.43%, p < 0.05; 31.44% versus 18.67%, p < 0.05; 40.21% versus 27.14%, p < 0.05), and the multiple pregnancy rates in both groups were comparable (34.09% versus 36.36%, p > 0.05). The observed results in OHSS-risk population allow us to take a position in favor of blastocyst transfer, thus pregnancy and live birth could be achieved with fewer ETs and in a shorter time frame.

Fertility preservation in young patients' with cancer

Preservation of fertility is an important issue in the management of young cancer patients. Though embryo cryostorage is a well-established procedure, it can only be availed by couples. Recent studies have indicated increasing success rates with mature and immature oocyte cryopreservation. Cryostorage induces injuries on the human oocytes which can be minimized by slow freezing and vitrification. Selection of candiidates is crucial so that the most suitable technique can be offered without any delay in initiation of cancer therapy. Factors affecting suitability are age of patient, assessment of ovarian reserve, hormonal status and type and stage of neoplastic disease. Encouraging results have been obtained with oocyte in vitro maturation (IVM) followed by vitrification for cryostorage. Data on the use of vitrified eggs in routine in vitro fertilization (IVF) show that pregnancy rates can be comparable to those achieved with fresh oocytes.

In high responding patients undergoing an initial IVF cycle, elevated estradiol on the day of hCG has no effect on live birth rate

BACKGROUND

The impact of elevated estradiol on the day of human chorionic gonadotropin (hCG) administration on in vitro fertilization (IVF) outcomes has been debated for over 25 years. Some investigators have shown a positive effect, others a negative effect; while most have shown no effect. Few studies have expressed their findings based on live birth. This study examined the relationship between estradiol level and other IVF cycle response parameters in relation to pregnancy, with a focus on live births after controlling for embryo quality.

METHODS

We performed a retrospective cohort study on 489 patients <40 years old that underwent an initial IVF cycle. Estradiol concentration on the day of hCG was categorized as; low <2000 pg/ml), mid (2001-4000 pg/ml) and high (>4000 pg/ml) to determine how estradiol level on the day of hCG affected response variables during the IVF cycle. We performed a subgroup analysis restricted to patients with good/fair quality embryos transferred (n=428), to control for embryo quality and assessed pregnancy outcome. The association between estradiol and live birth (LB) was then evaluated after identifying and controlling for confounding factors. Multivariate analysis was used to identify significant main effects and interactions in the model. Estradiol levels were also compared in patients having a LB or not (NLB) in both populations.

RESULTS

We found that estradiol was significantly related to + hCG, clinical pregnancy rate, age, and most other IVF cycle response variables. After performing the subgroup analysis controlling for embryo quality, we found that LB rates were not different. Only the main effects of average embryo quality at transfer (AEQS), age and transferring two embryos influenced LB. Estradiol levels were also compared in patients having a LB or NLB in both populations and was found to be higher/not different in LB patients. LB rates and AEQS were also not different in a subgroup of patients having an elevated level of estradiol (>4200 pg/ml) on the day of hCG in patients having embryo transfer on day 3 or day 5.

CONCLUSIONS

After controlling for embryo quality, elevated estradiol on the day of hCG had no effect on LB.

Impact of peak estradiol levels on reproductive outcome of intracytoplasmic sperm injection

Objective: To observe effect of peak estradiol (E2) levels on outcome after intra cytoplasmic sperm injection (ICSI).

Methods: Quasi experimental design conducted in “Islamabad Clinic Serving Infertile Couples” from June 2010 till August 2011. Down regulation with mid luteal suppression of 564 females aged 18-41 years was done with gonadotrophin releasing hormone agonist followed by controlled ovarian stimulation, ovulation induction (OI), oocytes pickup and embryo transfer. Samples for peak serum E2 at the time of OI was estimated by Enzyme Linked Immuno Sorbent Assay. The association of peak E2 with outcome groups of Intracytoplasmic sperm injection (ICSI) (Group I) beta hCG <5 m IU/ml, (Group II) with beta hCG>5 mI U/ml and no cardiac activity and (Group III) with beta hCG>5mIU/ml and cardiac activity on trans vaginal scan was identified. Statistical comparison by one way analysis of variance (ANOVA) via SPSS version 15 was done.

Results: A clinical pregnancy rate of 36% was achieved, pregnant females(Group III) had higher peak E2 2269 ± 80.97 as compared to 1419 ± 37.07 and 1807±90.28 pg/ml (mean ± SD) in Groups I and II respectively (p<0.0001) Elevated serum E2 was significantly associated with better oocyte recovery, fertilization, cleavage and implantation rates (p<0.0001) .

Conclusion: A high serum E2 measured on OI day can predict success of treatment after ICSI. Females who had high peak E2 had greater number of retrieved, mature and fertilized oocytes with thick endometrial lining that helped in implantation and clinical pregnancy.

The impact of supraphysiologic serum estradiol levels on peri-implantation embryo development and early pregnancy outcome following in vitro fertilization cycles

PURPOSE

To determine the impact of elevated serum estradiol levels (EE2-defined as levels > 90th percentile) on the day of hCG administration during IVF on oocyte fertilization, embryo development, implantation, clinical pregnancy and miscarriage rates.

METHODS

A total of 2,995 consecutive IVF cycles in 1,889 patients with non-donor oocyte retrieval resulting in fresh embryo transfer between 1/1/2005 and 12/31/2011 were analyzed. Cycles were stratified by serum E2 level on the day of hCG administration into those with levels >90th percentile and ≤ 90th percentile. Rates of normal fertilization, embryo development, positive pregnancy test, implantation, clinical pregnancy and spontaneous miscarriage were compared.

RESULTS

Serum estradiol above the 90th percentile on the day of hCG administration was associated with a significantly lower rate of normal fertilization (68.6 ± 20 vs. 71.6 ± 21, p = 0.02) when compared with patients with a lower serum estradiol threshold. The proportion of embryos that progressed from 2PN to 6-8 cell on day 3 was not different between the two groups. Although rates of positive pregnancy test (55.2 % vs. 57 %), implantation (26.4 % vs. 28.5 %) and clinical pregnancy (45.5 % vs. 49.4 %) were lower in patients with a higher estradiol threshold, these differences were not statistically significant. Similarly, there was no difference in the spontaneous miscarriage rates between the two groups (8.4 % vs. 7.1 %).

CONCLUSIONS

Serum estradiol levels above the 90th percentile on the day of hCG administration is associated with lower oocyte fertilization rate; however, such levels do not impact embryo development, implantation, clinical pregnancy or spontaneous miscarriage rates.

Association of serum estradiol levels on the day of hCG administration with pregnancy rates and embryo scores in fresh ICSI/ET cycles down regulated with either GnRH agonists or GnRH antagonists

PURPOSE

To investigate the interrelation between serum E2 level on hCG day, score of transferred embryos and pregnancy achievement.

METHODS

Records of 350 women aged 18-40 years who underwent ovarian hyperstimulation in fresh cycles down regulated either with GnRH agonist (n = 70) or GnRH antagonist (n = 280) followed by oocyte pick-up, ICSI and embryo transfer are retrospectively analyzed.

RESULTS

Median E2 levels on hCG day of cycles ending with and without pregnancy were similar (p = 0.308). ROC curve for AUC of E2 on hCG day with dependent variable pregnancy rate also demonstrated that the E2 level on hCG day cannot be used to predict pregnancy in IVF/ICSI cycles (AUC 0.532, 95 % confidence interval: 0.471-0.593). Grouping cycles according to their E2 levels on hCG day also did not demonstrate any detrimental effect of either low or high E2 levels on hCG day both in agonist and antagonist cycles. Pregnancy rates are strongly correlated with mean and total score of transferred embryos. Interrelation of E2 on hCG day and pregnancy rate is independent from score of transferred embryos.

CONCLUSIONS

E2 on hCG day is not correlated with pregnancy rates and cannot be used to predict pregnancy in neither agonist nor antagonist cycles, no matter its level or percentile is used.

Female fertility loss and preservation: threats and opportunities

BACKGROUND

Ovarian aging and cytotoxic treatments are the most common causes for fertility loss in women. With increasing numbers of young female survivors following cytotoxic cancer treatments, the issue of fertility preservation has assumed greater importance.

METHODS

We review the literature on the causes of female fertility loss as well as the recent advances in fertility preservation options and strategies that might be of interest to oncologists. Currently, several methods and techniques exist for fertility preservation of female patients with cancer including embryo freezing, ovarian protection techniques, oocyte cryopreservation, ovarian tissue cryopreservation followed by autotransplantation, and recently in vitro culture of ovarian tissue, follicles, and oocytes. Each method or technique has advantages and disadvantages related to current success rate, required delay in cancer treatment, sperm requirement, and risk of reintroducing cancer cells.

RESULTS

To date, embryo freezing is the only established method successfully and widely used for fertility preservation of female patients with cancer. The other methods are promising but still considered experimental.

CONCLUSION

Patient awareness, physician knowledge, early counseling, costs management, international registry, interdisciplinary networks, and research development are necessary to improve the current care in the field of female fertility preservation.

A decrease in serum estradiol levels after human chorionic gonadotrophin administration predicts significantly lower clinical pregnancy and live birth rates in in vitro fertilization cycles

BACKGROUND

Although close observation of serum estradiol (E2) levels remains a mainstay of assessing clinical response to controlled ovarian stimulation, the prognostic value of any change in E2 levels after administration of hCG remains unclear. The objective of this study is to evaluate the relationship between serum E2 response after hCG administration and the clinical pregnancy and live birth rates in fresh IVF cycles.

METHODS

We conducted a retrospective cohort study of women aged 21-45 years undergoing their first IVF cycle from 1999 to 2008 at a single practice. We compared the post-hCG serum E2 level with values on the day of hCG trigger. IVF cycles were stratified by post-hCG E2 response and appropriate parametric and non-parametric statistics were performed. Clinical intrauterine pregnancy and live births were the primary outcomes of interest. Multivariable logistic regression models were created to identify predictive factors associated with outcomes while adjusting for potential confounders.

RESULTS

Among the 1712 IVF cycles, 1065 exhibited a >10% increase (Group A), 525 had a plateau (± 10%, Group B) and 122 showed a >10% decrease (Group C) in post-hCG E2 levels. While the E2 levels on the day of hCG were similar across groups, Group C had more patients with diminished ovarian reserve, required higher gonadotrophin doses and had the lowest implantation rates. After adjusting for age, total gonadotrophin dose, infertility diagnosis, number of oocytes and number of transferred embryos, the associations between post-hCG E2 decline (Group C) and clinical pregnancy [adjusted odds ratio (aOR): 0.53; 95% confidence interval (CI): 0.33-0.84, P= 0.007] and live birth (aOR: 0.40; 95% CI: 0.22-0.71, P= 0.002) were significant. We also found significant associations between E2 plateau (Group B) and clinical pregnancy (aOR: 0.73; 95% CI: 0.57-0.94, P= 0.013) and live birth (aOR: 0.74; 95% CI: 0.56-0.97, P= 0.032) when adjusting for the same factors.

CONCLUSIONS

In our study, >10% decrease in E2 levels after hCG administration was associated with 40-50% reduction in clinical pregnancy and live birth rates. Similarly, post-hCG E2 plateau (± 10%) lowered the clinical pregnancy and live birth rates by >25%. Our study suggests that the change in the post-hCG E2 level is another parameter that can be used by clinicians to counsel patients regarding their likelihood of success with assisted reproductive technologies prior to oocyte retrieval.

Comparing thaw survival, implantation and live birth rates from cryopreserved zygotes, embryos and blastocysts

CONTEXT:

Most in vitro fertilization (IVF) programs employ embryo cryopreservation to enhance pregnancies from a single ovarian stimulation. More embryos are created, some of which are not transferred to the uterus immediately, generating a need for improved cryopreservation protocols. One protocol may involve growing embryos to a further stage of development, allowing only embryos with proven developmental capabilities to be cryopreserved. Here we examined thaw survival, implantation and live birth rates of embryos cryopreserved at different stages.

AIMS:

We examined thaw survival, implantation and live birth rates of embryos cryopreserved at the zygote, day 3 (D3) embryos or blastocyst stage.

SETTINGS AND DESIGN:

This is a retrospective study from a single academic IVF program.

PATIENTS AND METHODS:

A retrospective study of all patients who had frozen embryos transferred to their uteri from year 2002 to 2008 at a single academic IVF program was conducted.

STATISTICAL ANALYSIS USED:

Analysis of variance followed by Fisher's Exact Test was performed to compare the survival after thaw, implantation and live birth rates between the three groups.

RESULTS:

One thousand nine hundred and ninety-one zygotes, 2880 D3 embryos and 503 blastocysts were frozen using a slow freeze technique, thawed and transferred. Significantly more D3 embryos and blastocysts survived the thawing process compared to zygotes and significantly higher implantation rate per number of thawed blastocysts was achieved than that for zygotes. Live birth rates were similar between the three groups.

CONCLUSIONS:

Growing embryos to blastocyst stage prior to cryopreservation is associated with fewer frozen embryos but does not appear compromise patients’ chance of achieving pregnancy

Randomized controlled trial: effects of acupuncture on pregnancy rates in women undergoing in vitro fertilization

OBJECTIVE

To evaluate the influence of "true" versus "sham" acupuncture on pregnancy rates (PRs) in women undergoing IVF.

DESIGN

Randomized controlled trial, double-blinded with independent observer.

SETTING

Academic infertility clinic.

PATIENT(S)

One hundred sixty patients <38 years old undergoing IVF with or without intracytoplasmic sperm injection.

INTERVENTION(S)

Subjects were randomly allocated to the true or sham group and underwent acupuncture 25 minutes before and after ET. Subjects completed a McGill Pain Questionnaire regarding their clinical symptoms during ET.

MAIN OUTCOME MEASURE(S)

Clinical PR and clinical symptoms during ET.

RESULT(S)

While the overall clinical PR was 51.25%, there was no significant difference between the arms of the study (true = 45.3% vs. sham = 52.7%); 33.1% of the patients had ultrasound-documented singleton pregnancy, and 15% of patients had twin gestations, while one patient in the true arm had a triplet gestation. There were significant differences in the subjective, affective, and total pain experience between both arms. The subjects in the true arm described their acupuncture session as being more "tiring" and "fearful" and experienced more "achiness" compared with their sham counterparts.

CONCLUSION(S)

There was no statistically significant difference in the clinical or chemical PRs between both groups. Patients undergoing true acupuncture had differing sensory experiences compared with patients in the sham arm. There were no significant adverse effects observed during the study, suggesting that acupuncture is safe for women undergoing ET.

Preserving female fertility following cancer treatment: current options and future possibilities

Children and women of reproductive age are increasingly surviving cancer diagnoses, and therefore long-term quality-of-life issues are of greater importance at the time of diagnosis. Cancer therapies including radiation and chemotherapy can be detrimental to fertility, and therefore many patients are motivated to preserve fertility prior to cancer treatment. The only highly successful method in preserving fertility to date is embryo cryopreservation, which may not be appropriate for some patients due to age, delay in treatment, cancer type and stage, as well as availability of an acceptable sperm donor. Alternative methods including oocyte cryopreservation and ovarian tissue banking may also preserve fertility while providing additional flexibility to patients. In vitro ovarian follicle maturation following tissue banking is one potential approach that would not require a delay in cancer therapy for ovarian stimulation, would not require an immediate sperm donor, and does not carry the risk of reintroducing malignant cells following tissue transplantation. In vitro follicle culture systems have resulted in successful live births in the mouse. However, many challenges must be addressed in translating the system to the human. This review summarizes current approaches to fertility preservation and discusses recent developments and future challenges in developing a human in vitro follicle culture system.

Fertility preservation in female cancer survivors

The advancement of cancer therapies over the last few decades has significantly improved long-term survival of cancer patients, especially children and adolescents. As many of the therapeutic agents used are highly cytotoxic, cancer survivors have to pay the price of enduring various immediate and long-term side-effects. Unfortunately, gonadal failure and infertility are among the most common long-term side-effects, resulting in distress, lowered self-esteem and quality of life. Three modalities of fertility preservation can be offered to female patients prior to commencing their cancer treatment: embryo, oocyte and ovarian tissue cryopreservation. This paper reviews the outcomes for female patients who underwent fertility preservation in University College Hospital between 1995 and 2005, and post-therapeutic use of their frozen specimens. In addition, the effects of cytotoxic agents on fertility and ovarian function, and the range of fertility preservation available for female cancer sufferers are also discussed.

Body fat, energy balance and estradiol levels: a study based on hormonal profiles from complete menstrual cycles

BACKGROUND

Female fecundity is regulated by nutritional status. Although widely cited, this hypothesis is not strongly supported by empirical data from non-obese, healthy women of reproductive age.

METHODS

Healthy, reproductive aged women (n = 141) from Southern Poland collected daily morning saliva samples for one complete menstrual cycle. Levels of 17-beta-estradiol were analyzed by radioimmunoassay. Anthropometric measurements, including body fat percentage, were taken randomly with respect to phase of the menstrual cycle. Energy balance was specified based on changes in body fat percentage from the beginning to the end of the observation period.

RESULTS

Women with very low and high body fat had significantly lower levels of E2 compared with women with low and average body fat. In women of very low to average body fat, a 10% increase in body fat was associated with a 5-7 pmol/l increase in estradiol levels. The association between fat percentage and E2 was even stronger in women with positive energy balance, who also showed significant differences between body fat groups in estradiol profiles across whole the menstrual cycle. No such relationship was found in women with negative energy balance.

CONCLUSIONS

In healthy women, we found a non-linear association between body fat and estradiol levels. Both very low and high body fat was associated with decreased estradiol levels. The relationship between estradiol and body fat was strongly influenced by women's energy balance.

Dietary unsaturated fatty acids influence preovulatory follicle characteristics in dairy cows

Dietary unsaturated fatty acids (UFAs) have been implicated in several reproductive processes in dairy cows through a variety of mechanisms. This study examined the effects of periparturient supplementation of rumen bypass fats low or high in proportion of UFAs (oleic and linoleic) on preovulatory follicle characteristics. Forty-two 256-day pregnant dairy cows were divided into three groups and were fed a control diet (n=14) or supplemented with fats either low (LUFA; n=14) or high (HUFA; n=14) in UFAs. At 14-15 days following behavior estrus, the cows received a prostaglandin F(2)(alpha) injection and 48 h later >7 mm follicles were aspirated. Progesterone (P(4)), androstenedione (A(4)), and estradiol (E(2)) were determined in the follicular fluid. Out of 75 follicles, 37 follicles that were aspirated between 55 and 70 days post partum were regarded as E(2)-active follicles (E(2)/P(4) ratio >1) and subjected for further analysis. The diameter of preovulatory follicles was greater in cows fed HUFA than in those fed control or LUFA. The concentrations and content of A(4) and E(2) in follicles and E(2)/P(4) ratio were higher in the HUFA group than in the other two groups. The P450 aromatase mRNA expression in granulosa cells that were collected from the aspirated preovulatory follicles was also higher in the HUFA cows than in the other groups. A significant correlation was observed between E(2) concentrations in preovulatory follicles and E(2) concentrations in plasma at aspiration. In conclusion, dietary UFA increased the size of and elevated steroid hormones in preovulatory follicles, which may be beneficial to consequent ovarian function.

Early cleavage does not predict treatment outcome following the use of GnRH antagonists in women older than 35

OBJECTIVE

To compare the early-cleavage rates and the implantation potential of embryos between the GnRH antagonist and agonist long stimulation protocols in women older than 35 years.

DESIGN

Retrospective analysis.

SETTING

Academic medical center.

PATIENTS

Two hundred twenty patients older than 35 years old underwent IVF.

INTERVENTION(S)

Sixty-eight patients received GnRH antagonist protocol (GnRH antagonist group) and 152 patients received GnRH agonist long stimulation protocol (GnRH agonist group).

MAIN OUTCOME MEASURE(S)

Early-cleavage rate of zygotes, implantation rate, and pregnancy rate.

RESULT(S)

Early-cleavage rate of zygotes was significantly lower in the GnRH antagonist group than agonist group (21.8% vs. 32.6%, P<.0001). In the GnRH antagonist group, the pregnancy rate was not significantly different between the early-cleavage and late-cleavage subgroups (40.0% vs. 47.4%). In the GnRH agonist group, the pregnancy rate was significantly higher in the early-cleavage subgroup than in the late-cleavage subgroup (61.0% vs. 29.8%, P<.0001).

CONCLUSION(S)

In women older than 35 years, the early-cleavage rate of zygotes is significantly lower in the GnRH antagonist group than the agonist group. Early-cleavage status of zygotes is not a reliable predictor for embryo implantation in patients receiving the GnRH antagonist protocol.

Fertility preservation options for women with malignancies

Cancer is not rare in younger women. There has been a remarkable improvement in the survival rates due to progress in cancer treatment. The necessary treatment for most of the common cancer types occurring in younger women implies either removal of the reproductive organs or cytotoxic treatment that could partially or definitively affect reproductive function. Early loss of ovarian function not only puts the patients at risk for menopause-related complications at a very young age, but is also associated with loss of fertility. Further, women in the western hemisphere have been delaying initiation of childbearing to later in life. The results of these changes have led to an increase in patients facing the risk of premature ovarian failure, and therefore seeking help in preserving their fertility. This increase in demand has resulted in a proliferation of techniques to preserve fertility. Indeed, the number of options is increasing; some are more established procedures, such as embryo cryopreservation, and some are still experimental, such as ovarian cryopreservation. Because of the variations in type and dose of chemotherapy, the type of cancer, the time available before onset of treatment, the patient's age and the partner status, each case is unique and requires a different strategy of fertility preservation.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to recall the potential early loss of ovarian function secondary to radiotherapy and/or chemotherapy for cancer at a young age; explain the increasing demands for fertility preservation; and summarize the limited number of proven, safe, and efficacious methods.

Elevated oestradiol concentrations are not associated with increased first trimester miscarriage rates of singleton gestations conceived by assisted conception treatment

The study evaluated the impact of elevated oestradiol concentrations on pregnancy loss during the first trimester in singleton gestations conceived via ovarian stimulation and intracytoplasmic sperm injection (ICSI). Following determination of oestradiol concentrations during 6478 ICSI cycles, patients were assorted by oestradiol percentile. Hyper-responders were defined as patients having peak oestradiol concentrations over the 90th percentile (>4200 pg/ml, 685 cycles), moderate responders were defined as patients having peak oestradiol concentrations between the 75th and 90th percentiles (3250-4200 pg/ml, 958 cycles) and normal responders were defined as patients having peak oestradiol concentrations between the 25th and 75th percentiles (1350-3250 pg/ml, 3325 cycles). The relationship between first trimester miscarriage rates and oestradiol percentiles was analysed in 1184 singleton gestations. Pregnancy rate was significantly lower in normal responders (54.4%) than in moderate (58.8%, P = 0.02) and hyper-responders (60.9%, P = 0.003), but there were no intergroup differences in miscarriage rate (19.6%, 17.1%, and 16.8%, respectively). Although women with severe ovarian hyperstimulation syndrome had a miscarriage rate of 40%, this rate did not differ significantly from the miscarriage rates of the other groups. The findings suggest that high oestradiol concentrations during ovarian stimulation do not expose singleton pregnancies to an increased risk of miscarriage during the first trimester.

Subclinical pregnancy losses among women undergoing in-vitro fertilization with ICSI

BACKGROUND

The purpose of this study is to asses the frequency of subclinical pregnancy loss (SPL) among women undergoing controlled ovarian hyperstimulation (COH) and in-vitro fertilization with ICSI.

METHODS

The study was retrospectively conducted in a private IVF center. SPL was defined by a temporary rise in serum beta hCG, along with the absence of signs of intra- and extra-uterine pregnancy by transvaginal ultrasonography. Overall 5273 COH and ICSI cycles with embryo transfer (ET) were segregated according to serum E(2) levels percentiles (-24th, 25th, 74th, and 75th), women age and the type of spermatozoa for assisted fertilization (ejaculated and surgically retrieved). Those groups were assessed for SPL rates.

RESULTS

Among the 3125 (59.25) conception cycles, 305 (9.7%) were diagnosed as SPL. There was no difference in SPL rate among E(2) percentile groups. Women older than 35 years of age had significantly higher rate of SPL compared to younger women. There was also no difference in SPL rate among pregnancies in whom surgically retrieved spermatozoa used or ejaculated spermatozoa used for assisted fertilization.

CONCLUSION

Our results demonstrated that SPL rate was not influenced by the levels of E(2) during COH or the origin of spermatozoa used for assisted fertilization. However, maternal age was found to be detrimental for SPL.

Accelerated decline in pregnancy rate after in vitro fertilization and embryo transfer in 35-41-year-old women: 15 years' experience in the Okinawa Islands, Japan

Aim:  To describe 15 years of in vitro fertilization and embryo transfer (IVF-ET) treatment at University Hospital, with special reference to a potential association between pregnancy rate and patient age. Methods:  A retrospective analysis of 2355 IVF-ET cycles carried out in 789 patients was undertaken. The main outcome measures were ovarian response, fertilization rate and pregnancy rate. Results:  Pregnancy rates in ET cycles carried out in women aged between 23 and 46 years fell significantly with patient age, with a more rapid decline after 35 years and particularly between 35 and 41 years. Almost all laboratory findings were significantly worse with increased patient age, although fertilization rate did not drop with age. The spontaneous abortion rate increased drastically with age and the vast majority of abortions resulted from chromosomal abnormality. Conclusion:  It is essential to provide infertile women with practical and reliable information on the age-associated pregnancy rate for appropriate counseling and to encourage them to seek IVF-ET treatment at an earlier age. (Reprod Med Biol 2006; 5: 51-57).

Fertility preservation in female oncology patients

Survival rates for patients treated for the majority of childhood and young adult cancers have improved dramatically in recent years. Despite the high probability of survival, and often good quality of life in female survivors, until recently the concept of fertility preservation has not been seen to be an important component of the overall management of these patients. Over the last few years, various protection and preservation strategies have been developed, which may address potential reproductive concerns. Gametes or embryos may be frozen prior to potentially gonadotoxic cancer therapy, and ovarian tissue may be frozen and stored, with several pregnancies described after subsequent grafting. There is also increasing interest in the possibility of ovarian protection using gonadotrophin-releasing hormone analogues during chemotherapy, despite the lack of randomised controlled trials. Additionally, there are reports of novel protective strategies, including therapeutic alteration or manipulation of the sphingomyelin pathways. This review summarises methods of fertility protection and preservation currently available, as well as the emergence of promising new strategies.

Studies of gene expression in human cumulus cells indicate pentraxin 3 as a possible marker for oocyte quality

OBJECTIVE

To search for differentially expressed genes in cumulus cells from two groups of oocytes with different developmental outcome in vitro.

DESIGN

Analyses of gene expression in human cumulus cells from oocytes that failed to fertilize in vitro (group A) and those that developed into normal-appearing embryos on day 3 (group B).

SETTING

University-based facilities for clinical service and research.

PATIENT(S)

Women undergoing IVF treatment for infertility.

INTERVENTION(S)

Cumulus cells were collected from oocytes that were aspirated from ovarian follicles for IVF. The oocytes were cultured individually for IVF and embryo development. Total RNA was extracted from the cumulus cells for gene expression analyses.

MAIN OUTCOME MEASURE(S)

General gene expression profiles and relative abundance of pentraxin 3 (Ptx3) mRNA.

RESULT(S)

DNA microarray analysis identified 160 genes, including Ptx3, that were differentially expressed between cumulus cells in group A and group B. Quantitative analysis confirmed that the relative abundance of Ptx3 mRNA in cumulus cells was highly associated with oocyte development.

CONCLUSION(S)

This study demonstrated that changes in the expression levels of 160 genes, including particularly Ptx3, in human cumulus cells may be indicative of the quality of their enclosed oocyte.

Increased endometrial thickness is associated with improved treatment outcome for selected patients undergoing in vitro fertilization–embryo transfer

OBJECTIVE

To examine possible relationships between endometrial thickness and treatment outcome after IVF and embryo transfer, and to explore the role of potential confounding factors that may influence such relationships.

DESIGN

Retrospective study.

SETTING

A university-affiliated clinical IVF center.

PATIENT(S)

Patients undergoing IVF-embryo transfer with their own oocytes.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Endometrial thickness was determined on the day of hCG administration, 2 days before oocyte retrieval. Clinical pregnancy was confirmed by ultrasound observation of fetal heart activity.

RESULT(S)

The study analyzed 897 IVF-embryo transfer cycles. Treatment outcome (clinical pregnancy) after IVF-embryo transfer was positively associated with increased endometrial thickness and peak E(2) concentrations in serum, and negatively associated with advanced age. Endometrial thickness was dependent on peak E(2) concentrations in serum, but was independent of patient age or duration of ovarian stimulation. Thin endometrium reduced PRs in relatively young patients (<38 years old), in patients who required more than 10 days of gonadotropin stimulation, or in patients whose embryo transfers consisted of poor quality embryos.

CONCLUSION(S)

Increased endometrial thickness was associated with improved treatment outcome, but this association was dependent on patient age, duration of ovarian stimulation, and embryo quality.

Recurrent implantation failure in assisted reproduction: how to counsel and manage. A. General considerations and treatment options that may benefit the couple

Recurrent implantation failure is a distressing phenomenon, both for the infertile couple and for the physician responsible for their treatment. Aetiology is often not clear and treatment options are vague. Particularly when transferred embryos are of good quality, recurrent implantation failure may be attributed to less than optimal embryo transfer technique, pathological lesions of the uterine cavity, the presence of hydrosalpinges, fibroids and endometriosis. Poor embryo quality, especially when repetitive, is a major impediment to successful implantation and cannot be corrected at the present time. Molecular abnormalities at the endometrial level and abnormal embryo-endometrium dialogue may be responsible for some cases of recurrent implantation failure. Furthermore, there may be over- or under-expressed genes that may be related to successful implantation. At the present time, the physician confronted with a couple presenting with recurrent implantation failure should discuss openly the potential causes of this phenomenon, with special emphasis on correctable causes, and offer remedies that are evidence based.

Association of estradiol levels on the day of hCG administration and pregnancy achievement in IVF: a systematic review

BACKGROUND

Evaluation of the association between estradiol (E2) levels on the day of hCG administration and pregnancy achievement in IVF has so far yielded conflicting results. The purpose of the present study was to systematically review the above association in cycles down-regulated with GnRH analogues.

METHODS

Literature search was performed using Medline, Embase (1978-2004) and the Cochrane Library. Additionally, references of retrieved articles were hand-searched. Only full articles published in peer-reviewed medical journals were considered for analysis.

RESULTS

All the eligible studies (n=9) involved the use of GnRH agonists and were retrospective. Two studies (including 191 patients) suggested that the higher the E2 levels on the day of hCG administration, the higher the probability of pregnancy. However, five studies (including 1875 patients), did not support an association between E2 levels on the day of hCG administration and pregnancy rates. Moreover, two of the studies including (1286 patients) suggested that high E2 levels on the day of hCG administration are associated with a decreased probability of pregnancy. If we consider only studies in which criteria used for administering hCG include follicular development but not E2 levels (including 2687 patients), there is no study suggesting a positive association between E2 levels on the day of hCG administration and pregnancy achievement.

CONCLUSIONS

Currently there is no high-quality evidence to support or deny the value of E2 determination on the day of hCG administration for pregnancy achievement in IVF cycles, where pituitary down-regulation is performed with GnRH agonists. Existing retrospective studies suggest that there is no positive association. However, in order to arrive at recommendations for clinical practice, there is a need to perform well-designed prospective studies in both agonist and antagonist cycles.

Oestradiol, cyclodextrin-encapsulated 17beta-oestradiol and the oestradiol solubilizer 2-hydroxypropyl-beta-cyclodextrin all impair preimplantation mouse embryo development

The aim of this study was to examine the effects of 2-hydroxypropyl-beta-cyclodextrin (HbetaC) used as a solubilizer for oestradiol, 17beta-oestradiol (ethanol soluble) and HbetaC-encapsulated-17beta-oestradiol on mouse embryo development in vitro. HbetaC had no effect on day 3 development. In contrast, blastocyst development and blastocyst cell number were significantly reduced in the presence of 10(-4) mol/l solubilizer equivalent, but not at lower concentrations. The proportion of compacted embryos was significantly reduced with 10(-4) mol/l 17beta-oestradiol. No blastocysts were formed at 10(-4) mol/l concentration of 17beta-oestradiol, although the rate of blastocyst formation did not differ at lower concentrations. Blastocyst cell number was significantly decreased compared with controls at 10(-5) mol/l 17beta-oestradiol. The dose-response using HbetaC-encapsulated-17beta-oestradiol revealed that at 17beta-oestradiol concentrations of 10(-4) and 10(-5) mol/l, blastocyst development was significantly reduced. Blastocyst cell number was significantly reduced compared with controls for all concentrations of HbetaC-encapsulated-17beta-oestradiol. Exposure of embryos to 17beta-oestradiol (10(-4) mol/l) reduced blastocyst development on days 4 and 5 significantly in cultures initiated at the zygote, 2-cell and 8-cell, but not the morulae, stages of development. Trophectoderm, ICM and blastocyst cell numbers as well as percentage ICM development were reduced significantly, regardless of the stage of development. Therefore, 17beta-oestradiol does compromise embryo development.

Efficacy of blastocyst transfer after implantation failure

Clinicians who treat unsuccessful couples despite repeated transfers of good quality embryos face a challenge. Among the various strategies that have been described, embryo transfer at the blastocyst stage has been postulated to improve implantation. A prospective non-randomized analysis was performed in 276 IVF patients who failed to conceive after at least two early embryo transfers of at least two grade 1-2 embryos per cycle. For the next attempt, couples chose between day 2 embryo transfer (D2 group; n = 147) and day 5/6 blastocyst transfer (D5/D6 group; n = 129) before starting the following attempt. Embryo quality was assessed and results were expressed as clinical pregnancy, live birth and implantation rates per cycle. Embryo grade 1 number was similar between both groups, whereas mean embryo score of the whole cohort was slightly higher in the D2 group. The live birth rates per cycle (27.9 versus 19.7%) and implantation rates per cycle (25.4 versus 12.4%) were higher in the D5/D6 group compared with the D2 group. Improved embryo selection and uterine receptivity may explain the additional benefit of embryo transfer at the blastocyst stage for couples with repeated implantation failures.

Delay of embryo transfer to day 5 results in decreased initial serum β-human chorionic gonadotropin levels

OBJECTIVE

To investigate the impact of delaying the transfer of in vitro fertilized embryos to day 5 on embryo development by comparing serum beta-hCG levels in pregnancies established after day 3 embryo transfers and those after day 5 blastocyst transfers at equivalent time intervals after fertilization.

DESIGN

A retrospective analysis.

SETTING

Assisted reproductive technology center in an academic research environment.

PATIENT(S)

Women who had an embryo transfer procedure performed after in vitro fertilization (IVF) at Northwestern University's IVF Program between January 1999 and December 2001 were included in this study.

INTERVENTION(S)

Embryo transfer was performed either on day 3 or day 5 after oocyte retrieval for IVF (day 0), depending on the availability of good-quality embryos on day 3.

MAIN OUTCOME MEASURE(S)

Serum beta-hCG concentrations determined 13 and 15 days after fertilization in pregnancies established by transferring cleavage-stage embryos on day 3 or blastocysts on day 5.

RESULT(S)

In singleton pregnancies, serum beta-hCG concentrations were 75 +/- 54 (mean +/- SD, n = 203) or 62 +/- 41 (n = 109) IU/mL after day 3 or day 5 transfers, respectively. In twin pregnancies, the beta-hCG concentrations were 162 +/- 105 (n = 52) or 109 +/- 55 (n = 49) after day 3 or day 5 transfers, respectively. The percentage increases in beta-hCG concentrations between the first and second measurements were similar in the two groups (day 3: 144 +/- 109, day 5: 142 +/- 63, not statistically significant).

CONCLUSION(S)

Initial beta-hCG concentrations in pregnancies resulting from day 5 transfers were lower than those from day 3 transfers when assessed at equivalent intervals from fertilization. This suggests that embryo development or implantation may be impaired by the additional 2 days in culture.