The use of estradiol for luteal phase support in in vitro fertilization/intracytoplasmic sperm injection cycles: a systematic review and meta-analysis

Effect of estradiol supplementation on luteal support following a significant reduction in serum estradiol levels after hCG triggering: a prospective randomized controlled trial

OBJECTIVE

This study aimed to evaluate the impact of adding 4 mg estradiol valerate to progesterone for luteal support on pregnancy rates in IVF cycles following a long protocol with reduced luteal serum estradiol levels post-hCG triggering.

DESIGN, SETTING, AND PARTICIPANTS

The prospective randomized controlled trial was conducted at a public tertiary hospital reproductive center with 241 patients who experienced a significant decrease in serum estrogen levels post-oocyte retrieval.

INTERVENTIONS

Participants received either a daily 4 mg dose of estradiol valerate in addition to standard progesterone or standard progesterone alone for luteal support.

RESULTS

The ongoing pregnancy rate did not show a significant difference between the E2 group and the control group (56.6% vs. 52.2%, with an absolute rate difference (RD) of 4.4%, 95% CI -0.087 to 0.179, P = 0.262). Similarly, the live birth rate, implantation rate, clinical pregnancy rate, early abortion rate, and severe OHSS rate were comparable between the two groups. Notably, the E2 group had no biochemical miscarriages, contrasting significantly with the control group (0.0% vs. 10.7%, RD -10.7%, 95% CI -0.178 to -0.041, P = 0.000). In the blastocyst stage category, the clinical pregnancy rate was notably higher in the E2 group compared to the control group (75.6% vs. 60.8%, RD 14.9%, 95% CI 0.012 to 0.294, P = 0.016).

CONCLUSION

Adding 4 mg estradiol valerate to progesterone for luteal support does not affect the ongoing pregnancy rate in embryo transfer cycles using a long protocol with a significant decrease in serum estradiol levels after hCG triggering. However, it may reduce biochemical miscarriages and positively impact clinical pregnancy rates in blastocyst embryo transfer cycles.

TRIAL REGISTRATION

ChiCTR1800020342.

The impact of estradiol supplementation on endometrial thickness and intrauterine insemination outcomes

The impact of estrogen supplementation during the follicular/proliferative phase on the endometrial lining thickness (EMT) prior to intrauterine insemination (IUI) remains largely unstudied. Our study examined changes in EMT and rates of clinical pregnancy, miscarriage, and live birth for all patients who completed an IUI cycle at Stanford Fertility Center from 2017-2023 (n = 2281 cycles). Cycles with estradiol supplementation (n = 309) were compared to reference cycles without supplementation (n = 1972), with the reference cohort further categorized into cycles with a pre-ovulatory EMT of < 7 mm ("thin-lining", n = 536) and ≥ 7 mm ("normal-lining", n = 1436). The estradiol group had a statistically significant greater change in EMT from baseline to ovulation compared to the thin-lining reference groups (2.4 mm vs 1.9 mm, p < =0.0001). Similar rates of clinical pregnancy and live birth were observed. After adjusting for age, BMI, race/ethnicity, infertility diagnosis, and EMT at trigger, the estradiol cohort had a significantly increased odds of miscarriage versus the entire reference cohort (2.46, 95 % confidence interval [1.18, 5.14], p = 0.02). Thus, although estradiol supplementation had a statistically significant increase in EMT compared to IUI cycles with thin pre-ovulatory EMT (<7 mm), this change did not translate into improved IUI outcomes such as increased rates of clinical pregnancy and live birth or decreased rate of miscarriage. Our study suggests that supplemental estradiol does not appear to improve IUI outcomes.

Peri-implantation estradiol level has no effect on pregnancy outcome in vitro fertilization- embryo transfer

Background

The necessity of monitoring luteal endocrine functions in in vitro fertilization- embryo transfer (IVF-ET) remains uncertain. Specifically, the significance of luteal phase estradiol (E2) levels is a matter of debate in current literature.

Objective

To assess the impact of luteal phase (day 11 after HCG trigger) estradiol levels on IVF-ET outcomes.

Design

Twelve thousand five hundred and thirty-five (n = 12,535) IVF-ET cycles performed in our center between 2015 and 2021 were divided into 5 groups based on the middle and late luteal phase serum E2 (MllPSE2) level percentiles as follows: Group A < 50 pg/mL (N=500), group B 50 pg/mL≤E2<150 pg/mL (N=2545), group C 150 pg/mL≤E2<250 pg/mL (N=1327), group D 250 pg/mL≤E2<500 pg/mL (N=925), group E E2≥500 pg/mL (n=668). The clinical pregnancy rates, abortion rates, and live birth rates of each group were compared. Binary logistic regression analysis was carried out to assess the potential impact of MllPSE2 on the live birth rate (LBR).

Results

No significant differences were found in various parameters when comparing the five groups. The level of MllPSE2 showed no significant difference between the pregnant group and the non-pregnant group. The binary logistic regression analysis model demonstrated that MllPSE2 was not significantly related to LBR.

Conclusion

The influence of E2 during the peri-implantation period (day 11) on clinical outcome in IVF-ET is not affected, even if E2<50 pg/mL. It is speculated that ovarian-derived E2 in MllPSE2 is not deemed necessary for endometrial receptivity. Although caution is warranted due to the retrospective nature of the analysis and the potential for unmeasured confounding, it is argued that the need for luteal E2 monitoring in IVF-ET may be of questionable value.

Estrogen in Luteal Phase Support: Effects on IVF-ICSI Antagonist Protocol Pregnancy Results

Aim: This study aimed to investigate the effect of luteal phase support (LPS) with estradiol in addition to progesterone on pregnancy outcomes in patients who underwent ovulation induction with GnRH antagonist protocol in in vitro fertilization- intracytoplasmic sperm injection (IVF-ICSI). Materials and Methods: This retrospective study was carried out at reproductive medicine center of Necmettin Erbakan University Meram Medical Faculty. The study enrolled 128 patients undergoing ICSI on an antagonist protocol for controlled ovarian hyperstimulation. Study group administered 7.8 mg transdermal estradiol (E2) daily in addition to progesterone for LPS (n=64). Control group administered only progesterone for LPS (n=64). All women received 200 mg progesterone 3x1 intravaginal daily and 50 mg progesterone intramuscular injection per two days for LPS. Blood samples were drawn 12 days after embryo transfer for β-hCG. If the result is negative, treatment was discontinued, if positive, estradiol was discontinued and progesterone support was continued until the 10th week of gestation. Pregnancy outcomes were the main endpoint. Results: There was no difference between groups in terms of biochemical pregnancy, clinical pregnancy, abortus and ongoing pregnancy rates. Conclusion: In our study, the use of estrogen for luteal phase support in GnRH antagonist protocol did not show any difference on pregnancy outcomes.

Is there any correlation between Estradiol supplementation, as luteal phase support, and clinical pregnancy in ART cycles? A cross-sectional study

Background

Endometrial receptivity is one of the important factors in assisted reproductive technology (ART) success. In the luteal phase of an ART cycle, serum estradiol (E2) and progesterone are often placed in low levels. Supporting the luteal phase with progesterone is a usual method.

Objective

To evaluate the effects of E2 supplementation plus progesterone on the luteal phase support in the antagonist protocol who have undergone intracytoplasmic sperm injection-embryo transfer cycles.

Materials and Methods

In this cross-sectional study, 200 patients with antagonist stimulation protocol, who had undergone intracytoplasmic sperm injection treatment, were divided into two groups based on the use of E2 supplementation. In both groups, 400 mg progesterone suppositories (CyclogestⓇ), twice a day/vaginally, was administered starting from the day of oocyte collection until the fetal heart activity. However, in the E2 group, in addition to progesterone, 4 mg tablet of E2 was received daily. Beta hCG was checked 14 days after the embryo transfer, and the clinical pregnancy rate was the main endpoint.

Results

The patients' characteristics were matched, and insignificant differences were observed, except for endometrial thickness. The clinical outcomes showed the rate of pregnancy was higher in the E2 group compared to the control group; nonetheless, statistically, there was no noticeable difference.

Conclusion

E2 supplementation had no beneficial effect in the luteal phase support of IVF cycles. Nevertheless, more studies are required to confirm the supportive role of E2 supplementation for embryo implantation and to improve the outcomes in ART cycles.

Endometrial receptivity and pregnancy outcome

Human implantation is a highly complex and multifactorial process. Successful implantation requires the presence of a healthy embryo, a receptive endometrium, and a synchronized molecular dialogue between the two, as well as immune tolerance/protection from the host. The endometrial receptivity refers to a hormonally limited period in which the endometrial tissue acquires a transient functional status allowing blastocyst implantation and pregnancy initiation. Global knowledge of endometrial receptivity grew up in recent years. Improvements in genetics, new biomarkers, noninvasive methods, new advanced techniques (Endometrial receptivity assay - the ERA system, proteomic analysis) offer the possibility to evaluate the endometrial status and to manage patients with infertility problems, especially women undergoing assisted reproductive treatment. This overview reports the most relevant knowledge and recent advances in the study of implantation processes from the perspective of the endometrium, often considered as being the main barrier for a successful pregnancy initiation. Endometrial receptivity is a topic of great interest and further studies are needed for the early identification of endometrial abnormalities and the discovery of new strategies for increasing the chance for the establishment of pregnancy.

Evaluation of progestogen supplementation for luteal phase support in fresh in vitro fertilization cycles

OBJECTIVE

To evaluate the effectiveness of progestogen supplementation in improving clinical pregnancy rates in women undergoing fresh IVF cycles and to compare different routes, start times, durations, and estrogen coadministration regimen.

DESIGN

Comprehensive systematic review and meta-analysis.

SETTING

University.

PATIENT(S)

Women undergoing fresh IVF cycles who did and did not receive progestogen supplementation.

INTERVENTION(S)

Summary odds ratios (ORs) were calculated by binomial logistic regression.

MAIN OUTCOME MEASURE(S)

Clinical pregnancy rates.

RESULT(S)

Eighty-two articles (26,726 women) were included. Clinical pregnancy rates were increased by IM (OR = 4.57), vaginal (OR = 3.34), SC (OR = 3.36), or oral (OR = 2.57) progestogen supplementation versus no treatment. The greatest benefit was observed when progestogens were supplemented IM versus vaginally (OR = 1.37). The optimal time to commence administration was between oocyte retrieval and ET (OR = 1.31), with oocyte retrieval +1 day being most beneficial. Coadministration of estrogen had no benefit (OR = 1.33), whether progestogens were coadministered vaginally or IM. Clinical pregnancy rates were equivalent when progestogen supplementation was ceased after ≤3 weeks or continued for up to 12 weeks (OR = 1.06).

CONCLUSION(S)

This broad-ranging meta-analysis highlights the need to reevaluate current clinical practice. The use of progestogens in fresh IVF cycles is substantially beneficial to clinical pregnancy. Critically, the use of IM progestogens should not be dismissed, as it yielded the greatest clinical pregnancy rates. Pregnancy success was impacted by initiation of therapy, with 1 day after oocyte retrieval being optimal. There is little evidence to support coadministration of estrogen or prolonging progestogen treatment beyond 3 weeks.

Luteal oestradiol for patients with serum oestradiol levels lower than expected per oocyte

Although the efficiency of progesterone in providing luteal phase support has been established, the role of oestradiol supplementation during the luteal phase remains controversial. We evaluated pregnancy outcomes of patients who had a ratio of serum E2 levels on the hCG day to the number of oocytes retrieved (oestradiol/oocyte ratio - EOR) levels of <100 pg/ml by supporting them with additional oestradiol during the luteal phase. In total, 150 patients with an EOR < 100 pg/ml of oestradiol undergoing antagonist intracytoplasmic sperm injection (ICSI) cycles were randomly assigned into two groups to receive either oral oestradiol (4 mg/d) plus vaginal progesterone (90 mg, 2 × 1/day) (group 1) or vaginal progesterone (90 mg, 2 × 1/d) alone (group 2). Implantation rate following transfer of a single embryo did not differ between the two groups (group 1 = 33.3%; group 2 = 34.9%; p = 0.85). Similarly, both groups gave comparable clinical pregnancy rates per embryo transfer with 31.7% in group 1 compared with 28.6% in group 2 (p = 0.69). In conclusion the study suggests that the addition of 4 mg oral E2 to progesterone does not increase the probability of pregnancy.

Plasmatic estradiol concentration in the mid-luteal phase is a good prognostic factor for clinical and ongoing pregnancies, during stimulated cycles of in vitro fertilization

Objective

To evaluate the predictive efficiency of serum estradiol (E₂) concentration in the mid-luteal phase regarding chemical, clinical, and ongoing pregnancies, in patients subjected to IVF/ICSI with fresh embryo transfer.

Methods

One hundred and forty-three patients undergoing IVF/ICSI met all the inclusion criteria for the present study. Most of the patients used antagonists, final maturation was achieved with recombinant chorionic gonadotrophin (HCG), and embryo transfer took place on days 3 to 5, but mostly on day 4. The luteal phase was supplemented with estradiol valerate 6 mg/day and vaginal micronized progesterone 600 mg/day. There was no exclusion of patients in the embryo transfer group due to age or ovarian reserve. All patients with estradiol and chorionic gonadotrophin (βHCG) dosage on the day of transfer, day 7, were included. We assessed the following variables, initially regarding age: number of eggs collected, formed embryos, embryos transferred, day of transfer, transfer type, estradiol and chorionic gonadotropin. Next, we evaluated these elements at three different ranges of estradiol concentrations (<200 pg/ml, 200-500 pg/ml, and >500 pg/ml), comparing these parameters in pregnant (P) and non-pregnant (NP) patients.

Results

Data analysis by age group in P and NP patients showed significant differences in the mean values of the variables E₂ and βHCG, TD7. Mean serum estradiol levels in P and NP in the three age groups were: <35years, 835/417 p=0.0006, 35-39 years 833/434 p=0.0118, >39 years, 841/394 p=0.0012. There was also a significant difference in pregnancy rates in the group >500 pg/ml of estradiol concentration (63.4%, p=0.0096). The likelihood of chemical and clinical abortions for the estradiol ranges were: 38.46%, involving the two first ranges versus 15.15% for a concentration >500 pg/ml, p=0.0412 and 5.26% for a concentration >900 pg/ml, p=0.0105. The Pearson correlation coefficient for HCG and estradiol was r = 0.5108.

Conclusion

This study showed the prognostic value of E₂ in the mid-luteal phase (TD7) for chemical, clinical, and ongoing pregnancies, and its concentration suggested that there is a moderately positive correlation with βHCG levels.

Luteal phase support with estradiol and progesterone versus progesterone alone in GnRH antagonist ICSI cycles: a randomized controlled study

In vitro fertilization (IVF) cycles are associated with a defective luteal phase. Although progesterone supplementation to treat this problem is standard practice, estrogen addition is debatable. Our aim was to compare pregnancy outcomes in 220 patients undergoing antagonist intracytoplasmic sperm injection (ICSI) cycles protocol. The patients were randomly assigned into two equal groups to receive either vaginal progesterone alone (90 mg once daily) starting on the day of oocyte retrieval for up to 12 weeks if pregnancy occurred or estradiol addition (2 mg twice daily) starting on the same day and continuing up to seven weeks (foetal viability scan). Primary outcomes were pregnancy and ongoing pregnancy rates per embryo transfer. Secondary outcomes were implantation and early pregnancy loss rates. Pregnancy rates showed no significant difference between group 1 (39.09%) and 2 (43.63%) (p value = 0.3). Similarly, both groups were comparable regarding ongoing pregnancy rate (32.7% group 1 and 36.3% group 2, p value = 0.1). Implantation rates showed no difference between group 1 (19.25%) and group 2 (23.44%) (p value = 0.2). Early pregnancy loss rates were comparable, with 6.3% and 7.2% in groups 1 and 2, respectively, (p value = 0.4). In conclusion, the addition of 4 mg estrogen daily to progesterone for luteal support in antagonist ICSI cycles is not beneficial for pregnancy outcome.

Estrogen supplementation to progesterone as luteal phase support in patients undergoing in vitro fertilization: systematic review and meta-analysis

Meta-analyses have found conflicting results with respect to the use of progesterone or progesterone plus estrogen as luteal phase support for in vitro fertilization (IVF) protocols involving gonadotropins and/or gonadotropin-releasing hormone analogs. The aim of the present study was to perform an updated meta-analysis on the efficacy of progesterone versus progesterone plus estrogen as luteal phase support. We searched the MEDLINE, Cochrane Library, and Google Scholar databases (up to March 18, 2014). The search terms were (estrogen OR estradiol OR oestradiol) AND (progesterone) AND (IVF OR in vitro fertilization) AND (randomized OR prospective). We did not limit the form of estrogen and included subjects who contributed more than 1 cycle to a study. The primary outcome was clinical pregnancy rate. Secondary outcomes were ongoing pregnancy rate, fertilization rate, implantation rate, and miscarriage rate. A total of 11 articles were included in the present analysis, with variable numbers of studies assessing each outcome measure. Results of statistical analyses indicated that progesterone plus estrogen treatment was more likely to result in clinical pregnancy than progesterone alone (pooled odds ratio 1.617, 95% confidence interval 1.059-2.471; P = 0.026). No significant difference between the 2 treatment regimens was found for the other outcome measures. Progesterone plus estrogen for luteal phase support is associated with a higher clinical pregnancy rate than progesterone alone in women undergoing IVF, but other outcomes such as ongoing pregnancy rate, fertilization rate, implantation rate, and miscarriage rate are the same for both treatments.

Meta-analysis of estradiol for luteal phase support in in vitro fertilization/intracytoplasmic sperm injection

OBJECTIVE

To evaluate whether the addition of E(2) for luteal phase support (LPS) in IVF/intracytoplasmic sperm injection (ICSI) could improve the outcome of clinical pregnancy.

DESIGN

Meta-analysis.

SETTING

University hospital center.

PATIENT(S)

Women underwent IVF or ICSI using the GnRH agonist or GnRH antagonist protocol.

INTERVENTION(S)

Progesterone alone or combined with E(2) for LPS.

MAIN OUTCOME MEASURE(S)

Clinical pregnancy rate per patient (CPR/PA), clinical pregnancy rate per ET, implantation rate, ongoing pregnancy rate per patient, clinical abortion rate, and ectopic pregnancy rate.

RESULT(S)

Fifteen relevant randomized controlled trials (RCTs) were identified that included a total of 2,406 patients. There was no statistical difference between E(2) + P group and P-only group regarding the primary outcome of CPR/PA for different routes of administration of E(2) (oral, vaginal, and transdermal) or other relevant outcome measures. No significant effect was observed for different daily doses of E(2) (6, 4, and 2 mg), even through oral medication in CPR/PA.

CONCLUSION(S)

The best available evidence suggests that E(2) addition during the luteal phase does not improve IVF/ICSI outcomes through oral medication, even with different daily doses. Furthermore, RCTs that study other administration routes are needed.

Assisted reproductive techniques

Assisted reproductive technologies (ART) encompass fertility treatments, which involve manipulations of both oocyte and sperm in vitro. This chapter provides a brief overview of ART, including indications for treatment, ovarian reserve testing, selection of controlled ovarian hyperstimulation (COH) protocols, laboratory techniques of ART including in vitro fertilization (IVF), and intracytoplasmic sperm injection (ICSI), embryo transfer techniques, and luteal phase support. This chapter also discusses potential complications of ART, namely ovarian hyperstimulation syndrome (OHSS) and multiple gestations, and the perinatal outcomes of ART.

Oral oestradiol supplementation as luteal support in IVF/ICSI cycles: a prospective, randomized controlled study

OBJECTIVE

To explore whether oral oestradiol (E2) supplementation (6 mg) in the luteal phase is beneficial to the outcome of patients undergoing gonadotrophin-releasing hormone agonist (GnRHa) long protocol in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles.

STUDY DESIGN

Prospective, randomized, controlled study at the IVF Clinic, Sun Yat-sen Memorial Hospital. In total, 402 patients with an indication for IVF or ICSI were recruited. Patients were prospectively randomized to receive either progesterone injection plus oral E2 supplementation (Group A, n=202) or progesterone injection alone (Group B, n=200) as luteal support after oocyte retrieval. The main outcome measure was the clinical pregnancy rate.

RESULTS

No significant difference in the clinical pregnancy rate or miscarriage rate was observed between Group A and Group B (50.9% vs 58.0%, 14.6% vs 11.2%; p>0.05). In different age subgroups (≤35 years and >35 years) all measurements were comparable in patients with or without E2 supplementation, as well as in subgroups with different E2 levels on the day of human chorionic gonadotrophin injection (E2≥3000 pg/ml and E2<3000 pg/ml).

CONCLUSION

Adding E2 as luteal support did not increase the clinical pregnancy rate or reduce the miscarriage rate. Routine use of a combination of E2 and progesterone as luteal support in GnRHa long protocol IVF/ICSI cycles is not recommended.

The impact of luteal phase support on endometrial estrogen and progesterone receptor expression: a randomized control trial

BACKGROUND

To assess the impact of luteal phase support on the expression of estrogen receptor (ER) alpha and progesterone receptors B (PR-B) on the endometrium of oocyte donors undergoing controlled ovarian hyperstimulation (COH).

METHODS

A prospective, randomized study was conducted in women undergoing controlled ovarian hyperstimulation for oocyte donation. Participants were randomized to receive no luteal support, vaginal progesterone alone, or vaginal progesterone plus orally administered 17 Beta estradiol. Endometrial biopsies were obtained at 4 time points in the luteal phase and evaluated by tissue microarray for expression of ER alpha and PR-B.

RESULTS

One-hundred and eight endometrial tissue samples were obtained from 12 patients. No differences were found in expression of ER alpha and PR-B among all the specimens with the exception of one sample value.

CONCLUSIONS

The administration of progesterone during the luteal phase of COH for oocyte donor cycles, either with or without estrogen, does not significantly affect the endometrial expression of ER alpha and PR.

Estradiol supplementation during the luteal phase in poor responder patients undergoing in vitro fertilization: a randomized clinical trial

PURPOSE

This study was designed to evaluate the effects of adding Estradiol (E2) supplementation to progesterone (P) on improvement of pregnancy outcomes in poor responder patients who underwent in vitro fertilization (IVF).

METHODS

In a prospective randomized clinical trial, 118 poor responder patients, older than 38 years without contraindications of estradiol consumption from Infertility clinic of a university hospital were randomly divided (by computerized software) into two groups. Control group (59 patients) received only P and intervention group (59 patients) received P and E2 (4 mg/d). Supplementation was done with 4 mg E2 in the luteal phase. Fertilization rate, implantation rate, biochemical and clinical pregnancy rates, abortion rate, ongoing pregnancy, multiple pregnancy and ectopic pregnancy rates were documented for those who completed the study protocol in each group (per protocol analysis) and compared between groups.

RESULT

Fifty five patients in control group and 53 patients in intervention group successfully completed the study protocol. Treatment outcomes were not significantly different between two groups.

CONCLUSION

For poor responder women who underwent IVF, addition of E2 to P supplementation could not significantly improve pregnancy outcomes.

The effect of luteal phase support protocol on cycle outcome and luteal phase hormone profile in long agonist protocol intracytoplasmic sperm injection cycles: a randomized clinical trial

OBJECTIVE

To study the effect of luteal phase support protocol on cycle outcome and luteal phase hormone profile, in long agonist protocol intracytoplasmic sperm injection (ICSI) cycles.

DESIGN

Prospective randomized trial.

SETTING

Private infertility center.

PATIENT(S)

Two hundred seventy-four women undergoing first ICSI cycles were randomized after ovum pickup into three groups of luteal support.

INTERVENTION(S)

Group I received IM P (P(4)) only, group II received P(4) + oral E(2) valerate, group III received P(4) + hCG.

MAIN OUTCOME MEASURE(S)

Pregnancy rate (PR), implantation rate, rates of multiple pregnancy and miscarriage, and midluteal serum E(2) and P(4), and midluteal E(2):P(4) ratio.

RESULT(S)

The PR and implantation rates were significantly higher in group II compared to group I and the miscarriage rate was significantly lower in group II compared with group I. Midluteal E(2) was significantly higher in group II compared with group I. The decline in E(2) after ovum pickup was lowest in group II, highest in group I. The midluteal E(2):P(4) ratio was significantly higher in group II compared with groups I and III.

CONCLUSION(S)

The E(2) luteal phase supplementation in long GnRH-agonist (GnRH-a) protocol ICSI cycles resulted in better cycle outcome and better luteal phase hormone profile.