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

Frozen-thawed embryo transfer: does the addition of low-dose choriogonadotropin alfa to progesterone in the luteal phase of artificial cycles improve the endometrium and increase the chances of pregnancy?

OBJECTIVE

Primary: To evaluate the effect of low doses of recombinant hCG (choriogonadotropin alfa) in the luteal phase of frozen-thawed embryo transfers (FET) of artificial cycles on the chances of pregnancy in patients aged ≤38years. Secondary: To assess the chances of pregnancy in the FET groups of artificial cycles using micronized vaginal progesterone (VP) versus injectable intramuscular progesterone (IMP) and the chances of pregnancy in type-1 embryo transfers (two top embryos).

METHODS

This retrospective cohort study included 122 cycles of FET and compared two groups of patients aged 38 years or younger, one given hCG in the luteal phase and one not administered hCG.

RESULTS

The clinical pregnancy rates (CPR) in the control and hCG groups were 45% and 45.16%, respectively (p=0.9999). The live birth rates (LBR) were 33.33% and 32.25%, respectively, (p=0.99909). The CPR in the VP group (83 patients) was 46.89% versus 41.02% in the IMP group, (p=0.5459). The LBR was 33.73% in the VP group and 30.76% in the IMP group (39 patients), (p=0.7559).

CONCLUSIONS

The CPR and LBR of patients undergoing FET in groups prescribed and not prescribed low doses of recombinant hCG were similar. No significant difference was found between patients given VP or IMP.

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.

Serum Progesterone Profile Across the Mid and Late Luteal Phase in Artificial Cycles Is Associated With Pregnancy Outcome

INTRODUCTION

Recent studies have shown that low serum progesterone levels on the day of embryo transfer (ET) are associated with poorer pregnancy outcome in hormonal replacement therapy cycles. It is of interest to know if serum progesterone levels during late luteal phase (following days after ET) are also related with the chances of ongoing pregnancy.

OBJECTIVE

To evaluate the luteal phase endocrine profile through measurements of serum progesterone and estradiol on days ET+4, ET+7 and ET+11, to test their predictive value in relation to pregnancy outcome.

SETTING

Private infertility center, Valencia, Spain.

MATERIALS AND METHODS

Prospective cohort study performed between June 2017 and August 2018. Eligible patients were aged between 18-42 years, with a normal uterus, and being transferred 1-2 good quality blastocysts in a frozen ET cycle after an artificial endometrial preparation with estradiol valerate and vaginal micronized progesterone (400 mg/12 hours).

RESULTS

A total of 127 patients were included. Mean age = 38.0 ± 3.9 years; BMI = 23.6 ± 3.6 kg/m2; endometrial thickness = 9.1 ± 1.6mm. Overall ongoing pregnancy rate = 47.2% (95%CI:38.3-56.3). Significantly higher levels of serum progesterone were observed on ET+4 (13.6 ± 6.0 vs. 11.1 ± 4.6ng/ml, p = 0.03) and ET+11 (15.7 ± 1.2 vs. 10.3 ± 0.6ng/ml, respectively; p = 0.000) in ongoing pregnancies versus negative β-hCG (β-human chorionic gonadotrophin) cases. On ET+7, ongoing pregnancies also had higher serum progesterone levels (14.2 ± 0.9 vs. 11.7 ± 0.8ng/ml, but did not reach statistical significance (p = 0.07). Serum estradiol levels were not related with pregnancy outcome at any moment of the luteal phase (p > 0.05). On days ET+4, +7 and +11, the ROC analysis showed that serum progesterone levels were predictive of ongoing pregnancy, and Pearson's coefficient showed a significant association (p<0.05) of serum β-hCG levels with serum progesterone.

CONCLUSIONS

In hormonal replacement therapy cycles, serum progesterone levels across luteal phase days are associated with pregnancy outcome. Ongoing pregnancies were associated with a higher exposure to progesterone in comparison with pregnancy losses or negative β-hCG. Therefore, serum progesterone might be playing an important role not only during implantation, but also in pregnancy maintenance. It remains unknown if the variability in serum progesterone levels among patients, after receiving the exact same progesterone dose for luteal phase support, is the cause or just a consequence of pregnancy results.