Rectal progesterone administration secures a high ongoing pregnancy rate in a personalized Hormone Replacement Therapy Frozen Embryo Transfer (HRT-FET) protocol: a prospective interventional study.

STUDY QUESTION: Can supplementation with rectal administration of progesterone secure high ongoing pregnancy rates (OPRs) in patients with low serum progesterone (P4) on the day of blastocyst transfer (ET)? SUMMARY ANSWER: Rectally administered progesterone commencing on the ET day secures high OPRs in patients with serum P4 levels below 35 nmol/l (11 ng/ml). WHAT IS KNOWN ALREADY: Low serum P4 levels at peri-implantation in Hormone Replacement Therapy Frozen Embryo Transfer (HRT-FET) cycles impact reproductive outcomes negatively. However, studies have shown that patients with low P4 after a standard vaginal progesterone treatment can obtain live birth rates (LBRs) comparable to patients with optimal P4 levels if they receive additionalsubcutaneous progesterone, starting around the day of blastocyst transfer. In contrast, increasing vaginal progesterone supplementation in low serum P4 patients does not increase LBR. Another route of administration rarely used in ART is the rectal route, despite the fact that progesterone is well absorbed and serum P4 levels reach a maximum level after ∼2 h. STUDY DESIGN, SIZE, DURATION: This prospective interventional study included a cohort of 488 HRT-FET cycles, in which a total of 374 patients had serum P4 levels ≥35 nmol/l (11 ng/ml) at ET, and 114 patients had serum P4 levels <35 nmol/l (11 ng/ml). The study was conducted from January 2020 to November 2022. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients underwent HRT-FET in a public Fertility Clinic, and endometrial preparation included oral oestradiol (6 mg/24 h), followed by vaginal micronized progesterone, 400 mg/12 h. Blastocyst transfer and P4 measurements were performed on the sixth day of progesterone administration. In patients with serum P4 <35 nmol/l (11 ng/ml), 'rescue' was performed by rectal administration of progesterone (400 mg/12 h) starting that same day. In pregnant patients, rectal administration continued until Week 8 of gestation, and oestradiol and vaginal progesterone treatment continued until Week 10 of gestation. MAIN RESULTS AND THE ROLE OF CHANCE: Among 488 HRT-FET single blastocyst transfers, the mean age of the patients at oocyte retrieval (OR) was 30.9 ± 4.6 years and the mean BMI at ET 25.1 ± 3.5 kg/m2. The mean serum P4 level after vaginal progesterone administration on the day of ET was 48.9 ± 21.0 nmol/l (15.4 ± 6.6 ng/ml), and a total of 23% (114/488) of the patients had a serum P4 level lower than 35 nmol/l (11 ng/ml). The overall, positive hCG rate, clinical pregnancy rate, OPR week 12, and total pregnancy loss rate were 66% (320/488), 54% (265/488), 45% (221/488), and 31% (99/320), respectively. There was no significant difference in either OPR week 12 or total pregnancy loss rate between patients with P4 ≥35 nmol/l (11 ng/ml) and patients with P4 <35 nmol/l, who received rescue in terms of rectally administered progesterone, 45% versus 46%, P = 0.77 and 30% versus 34%, P = 0.53, respectively. OPR did not differ whether patients had initially low P4 and rectal rescue or were above the P4 cut-off. Logistic regression analysis showed that only age at OR and blastocyst scoring correlated with OPR week 12, independently of other factors like BMI and vitrification day of blastocysts (Day 5 or 6). LIMITATIONS, REASONS FOR CAUTION: In this study, vaginal micronized progesterone pessaries, a solid pessary with progesterone suspended in vegetable hard fat, were used vaginally as well as rectally. It is unknown whether other vaginal progesterone products, such as capsules, gel, or tablet, could be used rectally with the same rescue effect. WIDER IMPLICATIONS OF THE FINDINGS: A substantial part of HRT-FET patients receiving vaginal progesterone treatment has lowserum P4. Adding rectally administered progesterone in these patients increases the reproductive outcome. Importantly, rectal progesterone administration is considered convenient, and progesterone pessaries are easy to administer rectally and of low cost. STUDY FUNDING/COMPETING INTEREST(S): Gedeon Richter Nordic supported the study with an unrestricted grant as well as study medication. B.A. has received unrestricted grant from Gedeon Richter Nordic and Merck and honoraria for lectures from Gedeon Richter, Merck, IBSA and Marckyrl Pharma. P.H. has received honoraria for lectures from Gedeon Richter, Merck, IBSA and U.S.K. has received grant from Gedeon Richter Nordic, IBSA and Merck for studies outside this work and honoraria for teaching from Merck and Thillotts Pharma AB and conference expenses covered by Merck. The other co-authors have no conflict of interest to declare. TRIAL REGISTRATION NUMBER (25): EudraCT no.: 2019-001539-29.

Can combining vaginal and rectal progesterone achieve the optimum progesterone range required for implantation in the HRT-FET model?

RESEARCH QUESTION: What is the ongoing pregnancy rate (OPR) in frozen embryo transfer (FET) cycles, using combined rectal and vaginal progesterone in hormonal replacement therapy (HRT)? DESIGN: A prospective cohort study (n = 277) including 239 HRT-FET cycles with serum progesterone measurements studying combined vaginal (90 mg/12 h) and rectal (90 mg/12 h) progesterone administration and single blastocyst transfer on the sixth day of progesterone administration. A total of 134 responses to questionnaires covering convenience and side-effects were collected. RESULTS: The median serum progesterone level was 45 nmol/l (range 2-150 nmol/l). Overall positive HCG rate, OPR at week 12 and pregnancy loss rates were 62%, 44% and 29%, respectively. A non-linear relationship between serum progesterone levels and OPR was found. Crude odds ratio for OPR in the high progesterone group (>45 nmol/l) was 0.56 (95% CI 0.32 to 0.98; P = 0.04) compared with the intermediate progesterone group (28-45 nmol/l). Discomfort after rectal progesterone administration was reported on the embryo transfer day and on the day of pregnancy scan 5 weeks later by a total of 18% (16/87) and 17% (8/47) of patients, respectively. Discomfort related to vaginal administration increased significantly over time and was reported by 18% (16/87) on the day of embryo transfer compared with 45% (21/47) on the day of pregnancy scan (P < 0.002). CONCLUSIONS: Combined rectal and vaginal progesterone in HRT-FET cycles resulted in higher median progesterone levels compared with vaginal administration alone. This study suggests that an upper threshold for serum progesterone exists and that above this concentration serum progesterone levels decrease the OPR. Rectally administered progesterone was well tolerated by patients.

The impact of luteal serum progesterone levels on live birth rates-a prospective study of 602 IVF/ICSI cycles.

STUDY QUESTION: Is the chance of a live birth following IVF treatment and fresh embryo transfer affected by early and mid-luteal serum progesterone (P4) levels? SUMMARY ANSWER: Low as well as high serum P4 levels in the early and mid-luteal phase reduce the chance of a live birth following IVF treatment with fresh embryo transfer. WHAT IS KNOWN ALREADY: Data from non-human studies and studies of frozen-thawed embryo transfer cycles indicate that low as well as high P4 levels during the mid-luteal phase decrease the chance of pregnancy. The altered P4 pattern may disrupt the endometrial maturation leading to asynchrony between embryonic development and endometrial receptivity, thereby, compromising implantation and early development of pregnancy. STUDY DESIGN, SIZE, DURATION: Prospective multicenter cohort study of 602 women undergoing IVF treatment. Patients were recruited from four Danish public Fertility Centers from May 2014 to June 2017. The study population was unselected, thus, representing a normal everyday patient cohort. Patients were treated in a long GnRH-agonist protocol or a GnRH-antagonist protocol and triggered for final oocyte maturation with either hCG or a GnRH-agonist. The same vaginal luteal support regimen was applied in all patients. PARTICIPANTS/MATERIALS, SETTING, METHODS: Serum P4 levels from the early or mid-luteal phase were correlated to positive hCG and live birth rates (delivery > gestational week 20). Patients were divided into four P4 groups based on raw data of P4 serum levels and reproductive outcomes during early luteal phase (P4<60 nmol/l, P4 60-100 nmol/l, P4 101-400 nmol/l and P4>400 nmol/l) and during mid-luteal phase (P4<150 nmol/l, P4 150-250 nmol/l, P4 251-400 nmol/l and P4>400 nmol/l). MAIN RESULTS AND THE ROLE OF CHANCE: The optimal chance of pregnancy was achieved with serum P4 levels of 60-100 nmol/l in the early luteal phase whereas the optimal P4 level during the mid-luteal phase was 150-250 nmol/l. Below, but most distinctly above these levels, the chance of pregnancy was consistently reduced. With an early luteal P4 level of 60-100 nmol/l, the chance of a positive hCG-test was 73%, 95% CI: [59, 84] following cleavage stage embryo transfer. In contrast, with P4 levels >400 nmol/l, the chance of a positive hCG-test was significantly reduced to 35%, 95% CI: [17, 57], thus, an absolute risk difference of -38%, P = 0.01. A similar negative association between early luteal P4 and live birth rate was found, although it did not reach statistical significance. During the mid-luteal phase, a P4 level of 150-250 nmol/l resulted in an optimal chance of live birth: 54%, 95% CI: [37, 70] compared to 38%, 95% CI: [20, 60] with a P4 level >400 nmol/l, thus, an absolute risk difference of -16%, P = 0.14. All estimates were adjusted for maternal age, maternal BMI, study site, final follicle count and late follicular P4 levels. LIMITATIONS, REASONS FOR CAUTION: This study is the first to explore the possible upper and lower thresholds for luteal P4 following IVF treatment and fresh embryo transfer, and the optimal P4 ranges found in this study should be corroborated in future clinical trials. Furthermore, the P4 thresholds in this study only apply to fresh IVF cycles, using vaginal luteal phase support, as the optimal P4 level in cycles using intramuscular P4 may be different. WIDER IMPLICATIONS OF THE FINDINGS: Future studies are necessary to explore whether additional exogenous luteal P4 supplementation in the low P4 group could increase the chance of a live birth following fresh embryo transfer, and whether patients with luteal P4 levels >400 nmol/l would benefit from segmentation followed by subsequent transfer in frozen/thawed cycles. TRIAL REGISTRATION NUMBER: NCT02129998 (Clinicaltrials.gov). STUDY FUNDING/COMPETING INTEREST(S): L.H.T. received an unrestricted grant from Ferring Pharmaceuticals, Denmark, to support this study. P.H. received unrestricted research grants from MSD, Merck, Gedeon Richter and Ferring Pharmaceuticals outside of this work as well as honoraria for lectures from MSD, Merck and Gedeon Richter outside of this work. U.K. received honoraria for lectures from MSD and Ferring Pharmaceuticals outside of this work. C.A. received unrestricted research grants from MSD, IBSA, and Ferring Pharmaceuticals outside of this work as well as honoraria for lectures from MSD and IBSA. H.O.E. and B.B.P. received an unrestricted research grant from Gedeon Richter outside of this work. K.E., L.B., D.P. and B.H. have no conflict of interest. Furthermore, grants from 'The Health Research Fund of Central Denmark Region', 'The Research Foundation of the Hospital of Central Jutland', 'The Research Foundation of A.P. Møller', 'The Research Foundation of Aase & Ejnar Danielsen', 'The Research Foundation of Dagmar Marshall', 'The Research Foundation of Dir. Jacob Madsen & Hustru Olga Madsen', 'The Research Foundation of Fam. Hede Nielsen' and 'The Danish Medical Research Grant' supported conducting this study. The providers of funding were neither involved in the conduction of the study nor in the writing of the scientific report.

Case of successful IVF treatment of an oligospermic male with 46,XX/46,XY chimerism.

INTRODUCTION: We present a case of an infertile male with 46,XX/46,XYchimerism fathering a child after ICSI procedure. METHODS: Conventional cytogenetic analysis on chromosomes, derived from lymphocytes, using standard Q-banding procedures with a 450-550-band resolution and short-tandem-repeat analysis of 14 loci. RESULTS: Analysis of 20 metaphases from lymphocytes indicated that the proband was a karyotypic mosaic with an almost equal distribution between male and female cell lines. In total, 12 of 20 (60%) metaphases exhibited a normal female karyotype 46,XX, while 8 of 20 (40%) metaphases demonstrated a normal male karyotype 46,XY. No structural chromosomal abnormalities were present. Out of 14 STR loci, two loci (D18S51 and D21S11) showed four different alleles in peripheral blood, buccal mucosal cells, conjunctival mucosal cells, and seminal fluid. In three loci (D2S1338, D7S820, and vWA), three alleles were detected with quantitative differences that indicated presence of four alleles. In DNA extracted from washed semen, four alleles were detected in one locus, and three alleles were detected in three loci. This pattern is consistent with tetragametic chimerism. There were no quantitative significant differences in peak heights between maternal and paternal alleles. STR-analysis on DNA from the son confirmed paternity. CONCLUSION: We report a unique case with 46,XX/46,XY chimerism confirmed to be tetragametic, demonstrated in several tissues, with male phenotype and no genital ambiguity with oligospermia fathering a healthy child after IVF with ICSI procedure.

GnRHa trigger and individualized luteal phase hCG support according to ovarian response to stimulation: two prospective randomized controlled multi-centre studies in IVF patients.

STUDY QUESTION: Does a GnRH agonist (GnRHa) trigger followed by a bolus of 1.500 IU hCG in a group of patients at risk of ovarian hyperstimulation syndrome (OHSS) reduce the OHSS incidence compared with hCG trigger? SUMMARY ANSWER: A GnRHa trigger followed by early luteal hCG support with one bolus of 1.500 IU hCG appears to reduce OHSS in patients at risk of OHSS; however, in a low-risk group a second bolus of 1.500 IU hCG induced two cases of late onset OHSS. WHAT IS KNOWN ALREADY: A GnRHa trigger is an alternative to hCG in GnRH antagonist co-treated cycles. STUDY DESIGN, SIZE, DURATION: Two RCTs were performed in four Danish IVF units. A total of 446 patients were assessed for eligibility and 390 patients were enrolled in the study from January 2009 until December 2011. The primary outcome of the study was OHSS incidence in the group at risk of OHSS. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients received a fixed dose of recombinant human FSH for the first 4 days. On the day of triggering, patients were assessed for their risk of OHSS based on the total number of follicles ≥11 mm diameter, and were classified as being at risk of OHSS when the total number of follicles ≥11 mm was between 15 and 25 and at low risk of OHSS when the total number of follicles ≥11 mm was ≤14. Two separate randomization lists were used for each of the OHSS risk groups. Women at risk of OHSS were allocated (RCT 1) to either: Group A (n = 60), ovulation triggering with a bolus of 0.5 mg buserelin (GnRHa) s.c. followed by a single bolus of 1.500 IU hCG s.c. after the oocyte retrieval-or: Group B (n = 58): 5.000 IU hCG. Similarly, women at low risk of OHSS were allocated (RCT 2) to receive either: Group C (n = 125), a bolus of 0.5 mg buserelin s.c., followed by a bolus of 1.500 IU hCG s.c. after oocyte retrieval and a second bolus of 1.500 IU hCG on the day of oocyte retrieval +5-or: Group D (n = 141), 5.000 IU hCG. Groups C and D were included in order to obtain preliminary data. MAIN RESULTS AND THE ROLE OF CHANCE: In women at risk of OHSS (RCT 1) (15-25 follicles) no OHSS case was seen in Group A (GnRHa trigger and one bolus of 1.500 IU hCG), whereas two cases of moderate late-onset OHSS occurred in group B (3.4%), (P = 0.24). In contrast, in women at a low risk of OHSS (RCT 2) (≤14 follicles) two cases of late-onset OHSS occurred in Group C (GnRHa trigger and two boluses of 1.500 IU hCG), whereas no OHSS case was encountered in Group D (P = 0.22). LIMITATIONS, REASONS FOR CAUTION: Although the first RCT was powered to include 168 patients at risk of OHSS (15-25 follicles ≥11 mm) randomized to either GnRHa trigger or hCG trigger, the trial was prematurely discontinued when a total of 118 patients at risk of OHSS were randomized. In addition the second RCT in the OHSS low-risk group was designed as a feasibility study to assess the incidence of OHSS after GnRHa trigger and dual hCG administration versus 5.000 IU hCG. No power calculation was performed for this trial. In addition, there was a lack of blinding in the RCTs. WIDER IMPLICATIONS OF THE FINDINGS: Although a non-significant result, one bolus of 1.500 IU hCG after GnRHa trigger tended to reduce the OHSS rate in patients with 15-25 follicles ≥11 mm as well as secure the ongoing pregnancy rate. In contrast, in patients at low risk of OHSS the administration of two boluses of 1.500 IU hCG after GnRHa trigger should be avoided as it may induce OHSS.