Oral versus transdermal oestrogen delivery for endometrial preparation before embryo transfer: a prospective, comparative, randomized clinical trial

Effect of estrogen exposure on pregnancy outcomes in artificial frozen-thawed embryo transfer cycles

In contemporary times, the employment of vitrification freezing technology has led to the widespread adoption of frozen-thawed embryo transfer (FET) worldwide. Meanwhile, hormone replacement therapy (HRT) is a crucial protocol for priming the endometrium during FET cycles. Estrogen is required in HRT cycles for the induction of progesterone receptors and to promote endometrial thickness. However, there is no universal consensus on the treatment duration, dosage regimen, administration route, and target serum estrogen levels. Therefore, this study aimed to offer a comprehensive review of these topics. A shorter duration of estrogen exposure may elevate the risk of early miscarriage, while prolonged exposure to estrogen does not seem to confer advantages to general population and may be attempted in individuals with thin endometrium. Moreover, excessive estrogen levels on the day of progesterone administration may be associated with higher miscarriage rates and lower live birth rates (LBR). To offer more comprehensive guidance for clinical practice, extensive and prospective studies involving a large sample size are warranted to determine the optimal concentration and duration of estrogen exposure.

Repair of spinal cord injury by bone marrow mesenchymal stem cell-derived exosomes: a systematic review and meta-analysis based on rat models

Objective

This study aims to systematically evaluate the efficacy of bone marrow mesenchymal stem cell-derived exosomes (BMSCs-Exo) in improving spinal cord injury (SCI) to mitigate the risk of translational discrepancies from animal experiments to clinical applications.

Methods

We conducted a comprehensive literature search up to March 2024 using PubMed, Embase, Web of Science, and Scopus databases. Two researchers independently screened the literature, extracted data, and assessed the quality of the studies. Data analysis was performed using STATA16 software.

Results

A total of 30 studies were included. The results indicated that BMSCs-Exo significantly improved the BBB score in SCI rats (WMD = 3.47, 95% CI [3.31, 3.63]), inhibited the expression of the pro-inflammatory cytokine TNF-α (SMD = -3.12, 95% CI [-3.57, -2.67]), and promoted the expression of anti-inflammatory cytokines IL-10 (SMD = 2.76, 95% CI [1.88, 3.63]) and TGF-β (SMD = 3.89, 95% CI [3.02, 4.76]). Additionally, BMSCs-Exo significantly reduced apoptosis levels (SMD = -4.52, 95% CI [-5.14, -3.89]), promoted the expression of axonal regeneration markers NeuN cells/field (SMD = 3.54, 95% CI [2.65, 4.42]), NF200 (SMD = 4.88, 95% CI [3.70, 6.05]), and the number of Nissl bodies (SMD = 1.89, 95% CI [1.13, 2.65]), and decreased the expression of astrogliosis marker GFAP (SMD = -5.15, 95% CI [-6.47, -3.82]). The heterogeneity among studies was primarily due to variations in BMSCs-Exo transplantation doses, with efficacy increasing with higher doses.

Conclusion

BMSCs-Exo significantly improved motor function in SCI rats by modulating inflammatory responses, reducing apoptosis, inhibiting astrogliosis, and promoting axonal regeneration. However, the presence of selection, performance, and detection biases in current animal experiments may undermine the quality of evidence in this study.

A randomized clinical trial of transdermal (gel) versus oral estrogen for endometrial preparation in frozen embryo transfer cycle

OBJECTIVE

The aim of this study was to compare endometrial thickness with the use of transdermal estrogen (gel) versus oral estrogen (pills) for endometrial preparation in the frozen embryo transfer cycle and serum estrogen concentrations during the preparation cycle, side effects, and chemical and clinical pregnancy rates.

METHODS

This was a prospective, randomized controlled trial of women undergoing endometrial preparation for cryopreserved blastocyst transfer. A total of 88 women were randomized, of which 82 completed the study protocol. Of this group, 44 received 6 mg/day of estradiol valerate orally (pills group) and 38 received 4.5 mg/day of estradiol hemihydrate transdermally (gel group). Endometrial thickness was measured using transvaginal ultrasound between the 7 and 10th day of the cycle. Serum estradiol concentrations were measured on the day of initiating the cycle, on control transvaginal ultrasounds, and on the day of embryo transfer. Side effects were documented at each study visit. p<0.05 were adopted as statistically significant. The groups were compared using Student's t-test for continuous variables and chi-square or Fisher's exact test for categorical variables.

RESULTS

There were no significant group differences (p>0.05) in endometrial thickness, biochemical and clinical pregnancy rates, miscarriage rate, blood estradiol concentrations, duration of estradiol administration, or cycle cancellation rates.

CONCLUSION

Endometrial preparation with transdermal estrogen yielded similar reproductive outcomes to oral estrogen with fewer side effects.

Nomogram for Predicting Live Birth after the First Fresh Embryo Transfer in Patients with PCOS Undergoing IVF/ICSI Treatment with the GnRH-Ant Protocol

Polycystic ovary syndrome (PCOS) is the leading cause of anovulatory infertility. A better understanding of factors associated with pregnancy outcomes and successful prediction of live birth after IVF/ICSI are important to guide clinical practice. This was a retrospective cohort study investigating live birth after the first fresh embryo transfer using the GnRH-ant protocol in patients with PCOS between 2017 and 2021 at the Reproductive Center of Peking University Third Hospital. A total of 1018 patients with PCOS were qualified for inclusion in this study. BMI, AMH level, initial FSH dosage, serum LH and progesterone levels on the hCG trigger day, and endometrial thickness were all independent predictors of live birth. However, age and infertility duration were not significant predictors. We developed a prediction model based on these variables. The predictive ability of the model was demonstrated well, with areas under the curve of 0.711 (95% CI, 0.672-0.751) and 0.713 (95% CI, 0.650-0.776) in the training cohort and validation cohort, respectively. Additionally, the calibration plot showed good agreement between the prediction and the observation (p = 0.270). The novel nomogram could be helpful for clinicians and patients in clinical decision-making and outcome evaluation.

A prospective study of oral estrogen versus transdermal estrogen (gel) for hormone replacement frozen embryo transfer cycles

AIM

This study was done to compare the efficacy of transdermal estrogen (gel) to oral estradiol in hormone replacement frozen embryo transfer cycles (HR- FET).

MATERIALS AND METHODS

This was a prospective study conducted between March 2019 and December 2019. We included 294 HR FET cycles: 156 cycles using oral estrogen tablets (oral group) and 138 cycles using transdermal gel (17 beta estradiol 0.06% w/w) (gel group). Primary objective of this study was to compare endometrial thickness (ET) on the day of progesterone start between the two groups. Our secondary objective was to compare implantation rates (IR), clinical pregnancy rates (CPR), miscarriage rates (MR), duration of estrogen administration, estradiol (E2) levels before the start of progesterone, cycle cancellation rates, patient satisfaction score and undesirable side effects between both the groups.

RESULTS

There was no significant difference in the ET, IR, CPR, MR and duration of E2 administration and cycle cancellation rates between both the groups. Patient satisfaction score was significantly higher (8.02 ± 1.07 vs 6.96 ± 0.99 p < .01) and side effects were significantly lower (18.1% vs 55.1%, p≤.01), in the gel group compared to the oral group.

CONCLUSION

This study concluded that transdermal estrogen (gel) is equally efficacious as oral estrogen in HR FET cycles with transdermal gel having an added benefit of better patient comfort with less side effects and better safety profile.

Endometrial preparation for frozen-thawed embryo transfer in an artificial cycle: transdermal versus vaginal estrogen

The objective was to compare the endometrial thickness (ET) in a frozen embryo transfer (FET) cycle between transdermal and vaginal estrogen. Our secondary objectives were to compare the patient satisfaction and the pregnancy outcomes. Prospective monocentric cohort study between 01/2017 and 12/2017 at a single institution. Choice of administration was left to the patient. 119 cycles had transdermal estrogen (T-group) and 199 had vaginal estrogen (V-group). The ET at 10 ± 1 days of treatment was significantly higher in the T-group compared to the V-group (9.9 vs 9.3 mm, p = 0.03). In the T-group, the mean duration of treatment was shorter (13.6 vs 15.5 days, p < 0.001). The rate of cycle cancelation was comparable between the two groups (12.6% vs 8.5%, p = 0.24). Serum estradiol levels were significantly lower (268 vs 1332 pg/ml, p < 0.001), and serum LH levels were significantly higher (12.1 ± 16.5 vs 5 ± 7.5 mIU/ml, p < 0.001) in the T-group. Patient satisfaction was higher in the T-group (p = 0.04) and 85.7% (36/42) of women who had received both treatments preferred the transdermal over the vaginal route. Live birth rates were comparable between the two groups (18% vs 19%, p = 0.1). Transdermal estrogen in artificial FET cycles was associated with higher ET, shorter treatment duration and better tolerance.