Initial and steady-state pharmacokinetics of a vaginally administered formulation of progesterone

Luteal phase support in assisted reproductive technology centers: Italian survey

BACKGROUND

In assisted reproductive cycles (ART), the fine balance of controlling corpus luteum function is severely disrupted. To challenge this iatrogenic deficiency, clinicians aim to provide exogenous support. Several reviews have investigated progesterone route of administration, dosage and timing.

METHODS

A survey about luteal phase support (LPS) after ovarian stimulation was conducted among doctors in charge in Italian II-III level ART centers.

RESULTS

With regards to the general approach to LPS, 87.9% doctors declare to diversify the approach; the reasons for diversifying (69.7%) were based on the type of cycle. For all the most important administration routes (vaginal, intramuscular, subcutaneous) it appears that in frozen cycles there is a shift towards higher dosages. The 90.9% of the centers use vaginal progesterone, and when a combined approach is required, in 72.7% of cases vaginal administration is combined with injective route of administration. When Italian doctors were asked about the beginning and duration of LPS, 96% of the centers start the day of the pickup or the day after, while 80% of the centers continue LPS until week 8-12. The rate of participation of the centers confirms the low perceived importance of LPS among Italian ART centers, while may be considered quite surprising the relatively higher percentage of centers that measures P level. Tailorization to women's needs is the new objective of LPS: self-administration, good tolerability are the main aspects for Italian centers.

CONCLUSIONS

In conclusion, results of Italian survey are consistent to results of main international surveys about LPS.

Circadian serum progesterone variations on the day of frozen embryo transfer in artificially prepared cycles

RESEARCH QUESTION

What is the intra-day variation of serum progesterone related to vaginal progesterone administration on the day of frozen embryo transfer (FET) in an artificial cycle?

DESIGN

A prospective cohort study was conducted including 22 patients undergoing a single blastocyst artificial cycle (AC)-FET from August to December 2022. Endometrial preparation was achieved by administering oestradiol valerate (2 mg three times daily) and consecutively micronized vaginal progesterone (MVP; 400 mg twice daily). A blastocyst FET was performed on the 6th day of MVP administration. Serum progesterone concentrations were measured on the day of transfer at 08:00, 12:00, 16:00 and 20:00 hours. The first and last blood samples were collected just before MVP was administered.

RESULTS

The mean age and body mass index of the study population were 33.95 ± 3.98 years and 23.10 ± 1.95 kg/m2. The mean P-values at 08:00, 12:00, 16:00 and 20:00 hours were 11.72 ± 4.99, 13.59 ± 6.33, 10.23 ± 3.81 and 9.28 ± 3.09 ng/ml, respectively. A significant decline, of 2.41 ng/ml (95% confidence interval 0.81-4.00), was found between the first and last progesterone measurements.

CONCLUSION

A statistically significant intra-day variation of serum progesterone concentrations on the day of FET in artificially prepared cycles was observed. This highlights the importance of a standardized procedure for the timing of progesterone measurement on the day of AC-FET. Of note, the study results are applicable only to women using MVP for luteal phase support; therefore it is necessary to confirm its validity in comparison with the different existing administration routes of progesterone.

Impact of a TAK-1 inhibitor as a single or as an add-on therapy to riociguat on the metabolic reprograming and pulmonary hypertension in the SUGEN5416/hypoxia rat model

Background: Despite increasing evidence suggesting that pulmonary arterial hypertension (PAH) is a complex disease involving vasoconstriction, thrombosis, inflammation, metabolic dysregulation and vascular proliferation, all the drugs approved for PAH mainly act as vasodilating agents. Since excessive TGF-β signaling is believed to be a critical factor in pulmonary vascular remodeling, we hypothesized that blocking TGFβ-activated kinase 1 (TAK-1), alone or in combination with a vasodilator therapy (i.e., riociguat) could achieve a greater therapeutic benefit.

Methods: PAH was induced in male Wistar rats by a single injection of the VEGF receptor antagonist SU5416 (20 mg/kg) followed by exposure to hypoxia (10%O2) for 21 days. Two weeks after SU5416 administration, vehicle, riociguat (3 mg/kg/day), the TAK-1 inhibitor 5Z-7-oxozeaenol (OXO, 3 mg/kg/day), or both drugs combined were administered for 7 days. Metabolic profiling of right ventricle (RV), lung tissues and PA smooth muscle cells (PASMCs) extracts were performed by magnetic resonance spectroscopy, and the differences between groups analyzed by multivariate statistical methods.

Results:In vitro, riociguat induced potent vasodilator effects in isolated pulmonary arteries (PA) with negligible antiproliferative effects and metabolic changes in PASMCs. In contrast, 5Z-7-oxozeaenol effectively inhibited the proliferation of PASMCs characterized by a broad metabolic reprogramming but had no acute vasodilator effects. In vivo, treatment with riociguat partially reduced the increase in pulmonary arterial pressure (PAP), RV hypertrophy (RVH), and pulmonary vascular remodeling, attenuated the dysregulation of inosine, glucose, creatine and phosphocholine (PC) in RV and fully abolished the increase in lung IL-1β expression. By contrast, 5Z-7-oxozeaenol significantly reduced pulmonary vascular remodeling and attenuated the metabolic shifts of glucose and PC in RV but had no effects on PAP or RVH. Importantly, combined therapy had an additive effect on pulmonary vascular remodeling and induced a significant metabolic effect over taurine, amino acids, glycolysis, and TCA cycle metabolism via glycine-serine-threonine metabolism. However, it did not improve the effects induced by riociguat alone on pulmonary pressure or RV remodeling. None of the treatments attenuated pulmonary endothelial dysfunction and hyperresponsiveness to serotonin in isolated PA.

Conclusion: Our results suggest that inhibition of TAK-1 induces antiproliferative effects and its addition to short-term vasodilator therapy enhances the beneficial effects on pulmonary vascular remodeling and RV metabolic reprogramming in experimental PAH.

Evaluation of biosynthesized silver nanoparticles effects on expression levels of virulence and biofilm-related genes of multidrug-resistant Klebsiella pneumoniae isolates

The emergence of multidrug-resistant (MDR) strains of Klebsiella pneumoniae is associated with high morbidity and mortality due to limited treatment options. This study attempts to biologically synthesize silver nanoparticles (AgNPs) and investigate their effect on expression levels of virulence and biofilm-related genes in clinically isolated K. pneumoniae. In this study, biofilm formation ability, antibiotic resistance pattern, extended-spectrum β-lactamases (ESBLs), and carbapenemases production were investigated for 200 clinical isolates of K. pneumoniae using phenotypic methods. Polymerase chain reaction (PCR) was used to detect virulence and biofilm-related genes, ESBL-encoding genes, and carbapenem resistance genes. AgNPs were synthesized using the bio-reduction method. The antibacterial effects of AgNPs were investigated by microdilution broth. In addition, the cytotoxic effect of AgNPs on L929 fibroblast cell lines was determined. The effects of AgNPs on K. pneumoniae virulence and biofilm-related genes (fimH, rmpA, and mrkA) were determined using quantitative real-time PCR. Thirty percent of the isolates produced a strong biofilm. The highest and lowest levels of resistance were observed against amoxicillin/clavulanic acid (95.4%) and tigecycline (96%), respectively. About 31% of isolates were considered positive for carbapenemases, and 75% of the isolates produced an ESBLs enzyme. Different frequencies of mentioned genes were observed. The synthesized AgNPs had a spherical morphology and varied in size. AgNPs inhibited the growth of MDR K. pneumoniae at 128 µg/ml. In addition, AgNPs downregulated the expression of fimH, rmpA, and mrkA genes by 10, 7, and 14-fold, respectively (p < 0.05), also exerted no cytotoxic effect on L929 fibroblast cell lines. It was revealed that AgNPs lead to a decrease in expression levels of virulence and biofilm-related genes; therefore, it was concluded that AgNPs had an excellent antibacterial effect on MDR K. pneumoniae.

Assessment of progesterone levels on the day of pregnancy test determination: A novel concept toward individualized luteal phase support

RESEARCH QUESTION

The main objective of the study is to define the optimal trade-off progesterone (P4) values on the day of embryo transfer (ET), to identify low P4-human chorionic gonadotropin (hCG), and to establish whether P4 supplementation started on the hCG day can increase the success rate of the frozen embryo transfer (FET) cycle.

DESIGN

A single-center, cohort, retrospective study with 664 hormone replacement therapy (HRT)-FET cycles analyzed female patients who received vaginal 600 mg/day of P4 starting from 6 days before the FET, had normal P4 values on the day before ET, and whose P4 on the day of the pregnancy test was assessed.

RESULTS

Of the 664 cycles, 69.6% of cycles showed P4 ≥ 10.6 ng/ml, while 30.4% showed P4 < 10.6 ng/ml on the day of the hCG. Of the 411 chemical pregnancies detected, 71.8% had P4-hCG ≥ 10.6 ng/ml (group A), while 28.2% had P4-hCG < 10.6 ng/ml. Of the cycles with P4-hCG < 10.6 ng/ml, 64.7% (group B) were supplemented with a higher dose of vaginal P4 (1,000 mg/day), while 35.3% (group C) were maintained on the same dose of vaginal micronized P4. The live birth rate was 71.9%, 96%, and 7.3% for groups A, B, and C, respectively.

CONCLUSION

The likelihood to detect P4-hCG < 10.6 ng/ml decreased as the level of serum P4 the day before ET increased. The live birth rate (LBR) was shown to be significantly lower when P4 was low and not supplemented.

The effect of frozen embryo transfer regimen on the association between serum progesterone and live birth: a multicentre prospective cohort study (ProFET)

STUDY QUESTION

What is the association between serum progesterone levels on the day of frozen embryo transfer (FET) and the probability of live birth in women undergoing different FET regimens?

SUMMARY ANSWER

Overall, serum progesterone levels <7.8 ng/ml were associated with reduced odds of live birth, although the association between serum progesterone levels and the probability of live birth appeared to vary according to the route of progesterone administration.

WHAT IS KNOWN ALREADY

Progesterone is essential for pregnancy success. A recent systematic review showed that in FET cycles using vaginal progesterone for endometrial preparation, lower serum progesterone levels (<10 ng/ml) were associated with a reduction in live birth rates and higher chance of miscarriage. However, there was uncertainty about the association between serum progesterone levels and treatment outcomes in natural cycle FET (NC-FET) and HRT-FET using non-vaginal routes of progesterone administration.

STUDY DESIGN SIZE DURATION

This was a multicentre (n = 8) prospective cohort study conducted in the UK between January 2020 and February 2021.

PARTICIPANTS/MATERIALS SETTING METHODS

We included women having NC-FET or HRT-FET treatment with progesterone administration by any available route. Women underwent venepuncture on the day of embryo transfer. Participants and clinical personnel were blinded to the serum progesterone levels. We conducted unadjusted and multivariable logistic regression analyses to investigate the association between serum progesterone levels on the day of FET and treatment outcomes according to the type of cycle and route of exogenous progesterone administration. Our primary outcome was the live birth rate per participant.

MAIN RESULTS AND THE ROLE OF CHANCE

We studied a total of 402 women. The mean (SD) serum progesterone level was 14.9 (7.5) ng/ml. Overall, the mean adjusted probability of live birth increased non-linearly from 37.6% (95% CI 26.3-48.9%) to 45.5% (95% CI 32.1-58.9%) as serum progesterone rose between the 10th (7.8 ng/ml) and 90th (24.0 ng/ml) centiles. In comparison to participants whose serum progesterone level was ≥7.8 ng/ml, those with lower progesterone (<7.8 ng/ml, 10th centile) experienced fewer live births (28.2% versus 40.0%, adjusted odds ratio [aOR] 0.41, 95% CI 0.18-0.91, P = 0.028), lower odds of clinical pregnancy (30.8% versus 45.1%, aOR 0.36, 95% CI 0.16-0.79, P = 0.011) and a trend towards increased odds of miscarriage (42.1% versus 28.7%, aOR 2.58, 95% CI 0.88-7.62, P = 0.086). In women receiving vaginal progesterone, the mean adjusted probability of live birth increased as serum progesterone levels rose, whereas women having exclusively subcutaneous progesterone experienced a reduction in the mean probability of live birth as progesterone levels rose beyond 16.3 ng/ml. The combination of vaginal and subcutaneous routes appeared to exert little impact upon the mean probability of live birth in relation to serum progesterone levels.

LIMITATIONS REASONS FOR CAUTION

The final sample size was smaller than originally planned, although our study was adequately powered to confidently identify a difference in live birth between optimal and inadequate progesterone levels. Furthermore, our cohort did not include women receiving oral or rectal progestogens.

WIDER IMPLICATIONS OF THE FINDINGS

Our results corroborate existing evidence suggesting that lower serum progesterone levels hinder FET success. However, the relationship between serum progesterone and the probability of live birth appears to be non-linear in women receiving exclusively subcutaneous progesterone, suggesting that in this subgroup of women, high serum progesterone may also be detrimental to treatment success.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by CARE Fertility and a doctoral research fellowship (awarded to P.M.) by the Tommy's Charity and the University of Birmingham. M.J.P. is supported by the NIHR Birmingham Biomedical Research Centre. S.F. is a minor shareholder of CARE Fertility but has no financial or other interest with progesterone testing or manufacturing companies. P.L. reports personal fees from Pharmasure, outside the submitted work. G.P. reports personal fees from Besins Healthcare, outside the submitted work. M.W. reports personal fees from Ferring Pharmaceuticals, outside the submitted work. The remaining authors have no conflict of interest to declare.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT04170517.

Clinical factors associated with low serum progesterone levels on the day of frozen blastocyst transfer in hormonal replacement therapy cycles

STUDY QUESTION

Which factors are associated with low serum progesterone (P) levels on the day of frozen embryo transfer (FET), in HRT cycles?

SUMMARY ANSWER

BMI, parity and non-European geographic origin are factors associated with low serum P levels on the day of FET in HRT cycles.

WHAT IS KNOWN ALREADY

The detrimental impact of low serum P concentrations on HRT-FET outcomes is commonly recognized. However, the factors accounting for P level disparities among patients receiving the same luteal phase support treatment remain to be elucidated, to help clinicians predicting which subgroups of patients would benefit from a tailored P supplementation.

STUDY DESIGN, SIZE, DURATION

Observational cohort study with 915 patients undergoing HRT-FET at a tertiary care university hospital, between January 2019 and March 2020.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Patients undergoing single autologous blastocyst FET under HRT using exogenous estradiol and vaginal micronized progesterone for endometrial preparation. Women were only included once during the study period. The serum progesterone level was measured in the morning of the FET, in a single laboratory. Independent factors associated with low serum P levels (defined as ≤9.8 ng/ml, according to a previous published study) were analyzed using univariate and multivariate logistic regression models.

MAIN RESULTS AND THE ROLE OF CHANCE

Two hundred and twenty-six patients (24.7%) had a low serum P level, on the day of the FET. Patients with a serum P level ≤9.8 ng/ml had a lower live birth rate (26.1% vs 33.2%, P = 0.045) and a higher rate of early miscarriage (35.2% vs 21.5%, P = 0.008). Univariate analysis showed that BMI (P < 0.001), parity (P = 0.001), non-European geographic origin (P = 0.001), the duration of infertility (P = 0.018) and the use of oral estradiol for endometrial preparation (P = 0.009) were significantly associated with low serum P levels. Moreover, the proportion of active smokers was significantly lower in the 'low P concentrations' group (P = 0.002). After multivariate analysis, BMI (odds ratio (OR) 1.06 95% CI (1.02-1.11), P = 0.002), parity (OR 1.32 95% CI (1.04-1.66), P = 0.022), non-European geographic origin (OR 1.70 95% CI (1.21-2.39), P = 0.002) and active smoking (OR 0.43 95% CI (0.22-0.87), P = 0.018) remained independent factors associated with serum P levels ≤9.8 ng/ml.

LIMITATIONS, REASONS FOR CAUTION

The main limitation of this study is its observational design, leading to a risk of selection and confusion bias that cannot be ruled out, although a multivariable analysis was performed to minimize this.

WIDER IMPLICATIONS OF THE FINDINGS

Extrapolation of our results to other laboratories, or other routes and/or doses of administering progesterone also needs to be validated. There is urgent need for future research on clinical factors affecting P concentrations and the underlying pathophysiological mechanisms, to help clinicians in predicting which subgroups of patients would benefit from individualized luteal phase support.

STUDY FUNDING/COMPETING INTEREST(S)

No funding/no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Clinical use of aqueous subcutaneous progesterone compared with vaginal progesterone as luteal support in in vitro fertilization: A randomized controlled study in Taiwan

OBJECTIVE

This study aims to compare the efficacy, tolerability and patient satisfaction between aqueous subcutaneous progesterone (Prolutex, 25 mg/vial; IBSA) and vaginal progesterone (Crinone, 90 mg/tube; Merck) as luteal support for fresh embryo transfers in in-vitro fertilization (IVF).

MATERIALS & METHODS

In this prospective randomized study, 65 patients who underwent IVF were recruited and randomly assigned to either the Prolutex (25 mg daily, n = 33) or Crinone (90 mg daily, n = 32) group. The luteal support regimens were given daily, starting from two days after oocyte pickup. If the serum pregnancy test was positive, luteal support was continued until 7 weeks of gestation. Primary outcomes were clinical pregnancy rate and serum progesterone level at the mid-luteal phase and at 4 weeks of gestation. Secondary outcomes were drug tolerability and patient satisfaction assessed by questionnaire.

RESULTS

There were no significant differences in clinical pregnancy rates (Prolutex 25.0% versus Crinone 33.3%, p = 0.699), serum progesterone levels and patient satisfaction between Prolutex and Crinone group. Although the patients that had received Prolutex complained of more local pain at the injection sites, they also had less annoying vaginal discharges and vulvar discomforts.

CONCLUSION

Prolutex is of comparable efficacy and patient satisfaction to Crinone, and its availability means patients have more options in regards to the routes of progesterone administration as luteal phase support during IVF.

Low Luteal Serum Progesterone Levels Are Associated With Lower Ongoing Pregnancy and Live Birth Rates in ART: Systematic Review and Meta-Analyses

Progesterone plays a key role in implantation. Several studies reported that lower luteal progesterone levels might be related to decreased chances of pregnancy. This systematic review was conducted using appropriate key words, on MEDLINE, EMBASE, and the Cochrane Library, from 1990 up to March 2021 to assess if luteal serum progesterone levels are associated with ongoing pregnancy (OP) and live birth (LB) rates (primary outcomes) and miscarriage rate (secondary outcome), according to the number of corpora lutea (CLs). Overall 2,632 non-duplicate records were identified, of which 32 relevant studies were available for quantitative analysis. In artificial cycles with no CL, OP and LB rates were significantly decreased when the luteal progesterone level falls below a certain threshold (risk ratio [RR] 0.72; 95% confidence interval [CI] 0.62-0.84 and 0.73; 95% CI 0.59-0.90, respectively), while the miscarriage rate was increased (RR 1.48; 95% CI 1.17-1.86). In stimulated cycles with several CLs, the mean luteal progesterone level in the no OP and no LB groups was significantly lower than in the OP and LB groups [difference in means 68.8 (95% CI 45.6-92.0) and 272.4 (95% CI 10.8-533.9), ng/ml, respectively]. Monitoring luteal serum progesterone levels could help in individualizing progesterone administration to enhance OP and LB rates, especially in cycles without corpus luteum.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=139019, identifier 139019.

Implantation Failures and Miscarriages in Frozen Embryo Transfers Timed in Hormone Replacement Cycles (HRT): A Narrative Review

The recent advent of embryo vitrification and its remarkable efficacy has focused interest on the quality of hormone administration for priming frozen embryo transfers (FETs). Products available for progesterone administration have only been tested in fresh assisted reproduction technologies (ARTs) and not in FET. Recently, there have been numerous concordant reports pointing at the inefficacy of vaginal preparations at delivering sufficient progesterone levels in a sizable fraction of FET patients. The options available for coping with these shortcomings of vaginal progesterone include (i) rescue options with the addition of injectable subcutaneous (SC) progesterone at the dose of 25 mg/day administered either solely to women whose circulating progesterone is <10 ng/mL or to all in a combo option and (ii) the exclusive administration of SC progesterone at the dose of 25 mg BID. The wider use of segmented ART accompanied with FET forces hormone replacement regimens used for priming endometrial receptivity to be adjusted in order to optimize ART outcomes.

Beyond the uterine first pass: optimizing programmed frozen embryo transfers. A mini-review

With the greatly increased popularity of segmented in vitro fertilization and frozen embryo transfers, progesterone replacement strategies in programmed cycles are being reexamined. Bidirectionality and the limited capacity of the uterine first pass provide an explanation for disconnects between the endometrial and serum levels when either vaginal or intramuscular progesterone is used alone. Whereas monotherapy departs from the physiology of spontaneous pregnancies, combined therapy provides physiologic replacement while minimizing the number of injections.

Progesterone and estrogen levels are associated with live birth rates following artificial cycle frozen embryo transfers

PURPOSE

Does an association exist between serum progesterone and estradiol levels and live birth rates in artificial cycle frozen embryo transfer (AC-FET)?

METHODS

Retrospective cohort study was based on prospectively collected data at a university-affiliated fertility center. Included were all cycles using an artificial endometrial preparation with estradiol hemihydrate (Estrofem, 2 mg/8 h) and vaginal progesterone (Endometrin 100 mg/8 h), autologous oocytes, and cleavage stage embryo transfers. Serum progesterone and estradiol levels were measured 14 days after FET. A total of 921 cycles in 568 patients from to December 2010 to June 2019 were investigated. Live birth was the primary outcome measure.

RESULTS

Significant association was found between live birth and progesterone as well as estradiol levels (progesterone 14.65 vs 11.62 ng/ml, p = 0.001; estradiol 355.12 vs 287.67 pg/ml, p = 0.001). A significant difference in live birth rate was found below and above the median progesterone level (10.9 ng/ml, p = 0.007). Lower estradiol level was significantly associated with lower live birth rate (< 188.2 pg/ml 8.3%, > 263.1 pg/ml 16%, p = 0.02).

CONCLUSIONS

Serum progesterone and estradiol levels impact live birth rate in AC-FET.

Micronized progesterone plus dydrogesterone versus micronized progesterone alone for luteal phase support in frozen-thawed cycles (MIDRONE): a prospective cohort study

STUDY QUESTION

Does the addition of oral dydrogesterone to vaginal progesterone as luteal phase support improve pregnancy outcomes during frozen embryo transfer (FET) cycles compared with vaginal progesterone alone?

SUMMARY ANSWER

Luteal phase support with oral dydrogesterone added to vaginal progesterone had a higher live birth rate and lower miscarriage rate compared with vaginal progesterone alone.

WHAT IS KNOWN ALREADY

Progesterone is an important hormone that triggers secretory transformation of the endometrium to allow implantation of the embryo. During IVF, exogenous progesterone is administered for luteal phase support. However, there is wide inter-individual variation in absorption of progesterone via the vaginal wall. Oral dydrogesterone is effective and well tolerated when used to provide luteal phase support after fresh embryo transfer. However, there are currently no data on the effectiveness of luteal phase support with the combination of dydrogesterone with vaginal micronized progesterone compared with vaginal micronized progesterone after FET.

STUDY DESIGN, SIZE, DURATION

Prospective cohort study conducted at an academic infertility center in Vietnam from 26 June 2019 to 30 March 2020.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We studied 1364 women undergoing IVF with FET. Luteal support was started when endometrial thickness reached ≥8 mm. The luteal support regimen was either vaginal micronized progesterone 400 mg twice daily plus oral dydrogesterone 10 mg twice daily (second part of the study) or vaginal micronized progesterone 400 mg twice daily (first 4 months of the study). In women with a positive pregnancy test, the appropriate luteal phase support regimen was continued until 7 weeks' gestation. The primary endpoint was live birth after the first FET of the started cycle, with miscarriage <12 weeks as one of the secondary endpoints.

MAIN RESULTS AND THE ROLE OF CHANCE

The vaginal progesterone + dydrogesterone group and vaginal progesterone groups included 732 and 632 participants, respectively. Live birth rates were 46.3% versus 41.3%, respectively (rate ratio [RR] 1.12, 95% CI 0.99-1.27, P = 0.06; multivariate analysis RR 1.30 (95% CI 1.01-1.68), P = 0.042), with a statistically significant lower rate of miscarriage at <12 weeks in the progesterone + dydrogesterone versus progesterone group (3.4% versus 6.6%; RR 0.51, 95% CI 0.32-0.83; P = 0.009). Birth weight of both singletons (2971.0 ± 628.4 versus 3118.8 ± 559.2 g; P = 0.004) and twins (2175.5 ± 494.8 versus 2494.2 ± 584.7; P = 0.002) was significantly lower in the progesterone plus dydrogesterone versus progesterone group.

LIMITATIONS, REASONS FOR CAUTION

The main limitations of the study were the open-label design and the non-randomized nature of the sequential administration of study treatments. However, our systematic comparison of the two strategies was able to be performed much more rapidly than a conventional randomized controlled trial. In addition, the single ethnicity population limits external generalizability.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings study suggest a role for oral dydrogesterone in addition to vaginal progesterone as luteal phase support in FET cycles to reduce the miscarriage rate and improve the live birth rate. Carefully planned prospective cohort studies with limited bias could be used as an alternative to randomized controlled clinical trials to inform clinical practice.

STUDY FUNDING/COMPETING INTERESTS

This study received no external funding. LNV has received speaker and conference fees from Merck, grant, speaker and conference fees from Merck Sharpe and Dohme, and speaker, conference and scientific board fees from Ferring; TMH has received speaker fees from Merck, Merck Sharp and Dohme, and Ferring; R.J.N. has received scientific board fees from Ferring and receives grant funding from the National Health and Medical Research Council (NHMRC) of Australia; BWM has acted as a paid consultant to Merck, ObsEva and Guerbet, and is the recipient of grant money from an NHMRC Investigator Grant.

TRIAL REGISTRATION NUMBER

NCT0399876.

Individualised luteal phase support in artificially prepared frozen embryo transfer cycles based on serum progesterone levels: a prospective cohort study

STUDY QUESTION

Does an individualised luteal phase support (iLPS), according to serum progesterone (P4) level the day prior to euploid frozen embryo transfer (FET), improve pregnancy outcomes when started on the day previous to embryo transfer?

SUMMARY ANSWER

Patients with low serum P4 the day prior to euploid FET can benefit from the addition of daily subcutaneous P4 injections (Psc), when started the day prior to FET, and achieve similar reproductive outcomes compared to those with initial adequate P4 levels.

WHAT IS KNOWN ALREADY

The ratio between FET/IVF has spectacularly increased in the last years mainly thanks to the pursuit of an ovarian hyperstimulation syndrome free clinic and the development of preimplantation genetic testing (PGT). There is currently a big concern regarding the endometrial preparation for FET, especially in relation to serum P4 levels around the time of embryo transfer. Several studies have described impaired pregnancy outcomes in those patients with low P4 levels around the time of FET, considering 10 ng/ml as one of the most accepted reference values. To date, no prospective study has been designed to compare the reproductive outcomes between patients with adequate P4 the day previous to euploid FET and those with low, but restored P4 levels on the transfer day after iLPS through daily Psc started on the day previous to FET.

STUDY DESIGN, SIZE, DURATION

A prospective observational study was conducted at a university-affiliated fertility centre between November 2018 and January 2020 in patients undergoing PGT for aneuploidies (PGT-A) IVF cycles and a subsequent FET under hormone replacement treatment (HRT). A total of 574 cycles (453 patients) were analysed: 348 cycles (leading to 342 euploid FET) with adequate P4 on the day previous to FET, and 226 cycles (leading to 220 euploid FET) under iLPS after low P4 on the previous day to FET, but restored P4 levels on the transfer day.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Overall we included 574 HRT FET cycles (453 patients). Standard HRT was used for endometrial preparation. P4 levels were measured the day previous to euploid FET. P4 > 10.6 ng/ml was considered as adequate and euploid FET was performed on the following day (FET Group 1). P4 < 10.6 ng/ml was considered as low, iLPS was added in the form of daily Psc injections, and a new P4 analysis was performed on the following day. FET was only performed on the same day when a restored P4 > 10.6 ng/ml was achieved (98.2% of cases) (FET Group 2).

MAIN RESULTS AND THE ROLE OF CHANCE

Patient's demographics and cycle parameters were comparable between both euploid FET groups (FET Group 1 and FET Group 2) in terms of age, weight, oestradiol and P4 levels and number of embryos transferred. No statistically significant differences were found in terms of clinical pregnancy rate (56.4% vs 59.1%: rate difference (RD) -2.7%, 95% CI [-11.4; 6.0]), ongoing pregnancy rate (49.4% vs 53.6%: RD -4.2%, 95% CI [-13.1; 4.7]) or live birth rate (49.1% vs 52.3%: RD -3.2%, 95% CI [-12; 5.7]). No significant differences were also found according to miscarriage rate (12.4% vs 9.2%: RD 3.2%, 95% CI [-4.3; 10.7]).

LIMITATIONS, REASONS FOR CAUTION

Only iLPS through daily Psc was evaluated. The time for Psc injection was not stated and no serum P4 determinations were performed once the pregnancy was achieved.

WIDER IMPLICATIONS OF THE FINDINGS

Our study provides information regarding an 'opportunity window' for improved ongoing pregnancy rates and miscarriage rates through a daily Psc injection in cases of inadequate P4 levels the day previous to FET (P4 < 10.6 ng/ml) and restored values the day of FET (P4 > 10.6 ng/ml). Only euploid FET under HRT were considered, avoiding one of the main reasons of miscarriage and implantation failure and overcoming confounding factors such as female age, embryo quality or ovarian stimulation protocols.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was received. B.C. reports personal fees from MSD, Merck Serono, Ferring Pharmaceuticals, IBSA and Gedeon Richter outside the submitted work. N.P. reports grants and personal fees from MSD, Merck Serono, Ferring Pharmaceuticals, Theramex and Besins International and personal fees from IBSA and Gedeon Richter outside the submitted work. The remaining authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

NCT03740568.

Comparing pregnancy outcomes between natural cycles and artificial cycles following frozen-thaw embryo transfers

BACKGROUND

Frozen embryo transfer (FET) is increasing in prevalence. In contrast to the amount of research performed on the actual cryopreservation procedure, there are limited data with respect to optimal endometrial preparation in FET cycles. Increasingly artificial cycle (AC) preparation is being adopted over the natural cycle (NC) to facilitate greater access to FET. However, there remains a paucity of data comparing pregnancy outcomes between these two commonly used cycle types.

AIMS

To examine the efficacy of AC vs NC following FET, by comparing pregnancy outcomes including biochemical, clinical and live birth rates, along with miscarriage rates.

MATERIALS AND METHOD

This is a large single-centre retrospective analysis, examining a standardised data set from January 2015 to July 2018. It included 3030 cycles (NC = 2033, AC = 997). Main outcomes were biochemical pregnancy (beta-human chorionic gonadotropin > 5 IU), ultrasound-diagnosed clinical pregnancy, and live births. Using the χ² test, the above pregnancy outcomes were compared between AC and NC. A multivariate logistic regression, controlling for factors such as age, embryo quality, and day of blastocyst freeze was further utilised to assess for confounding variables.

RESULTS

No difference was observed between biochemical pregnancy rates (NC = 39.45% vs AC = 37.71%, P = 0.357); statistically significant differences were observed between clinical pregnancy (30.84% vs 26.08%, P = 0.007), and live birth rates (24.40% vs 18.86% P = 0.001). Multivariate analysis confirmed that NC produces superior pregnancy outcomes when controlling for confounding variables.

CONCLUSION

This analysis demonstrates the non-inferiority of NC thaw compared to AC, on continuing pregnancy rates. Taken together with patient acceptability and possibly increased obstetric risks with AC, these findings support the use of NC when medically possible.

Factors associated with serum progesterone concentrations the day before cryopreserved embryo transfer in artificial cycles

RESEARCH QUESTION

What factors determine serum progesterone concentrations the day before cryopreserved embryo transfer in artificially prepared cycles?

DESIGN

Retrospective cohort study at a university-affiliated fertility centre including infertile women under 45 years old using own oocytes who underwent a total of 685 single cryopreserved blastocyst transfers under hormonal therapy. Determinants that affected live birth rate (LBR) were analysed using a multivariate logistic regression. Univariate analysis and multivariate linear regression were used to evaluate independent factors that affect serum progesterone concentrations.

RESULTS

Age (odds ratio [OR] 0.93; 95% confidence interval [CI] 0.89-0.96), duration of oestradiol (OR 0.96; 95% CI 0.92-0.99), serum progesterone concentrations (OR 1.04; 95% CI 1.01-1.08) and patients who underwent preimplantation genetic testing for aneuploidies (PGT-A) (OR 2.17; 95% CI 1.55-3.03) were independently associated with LBR. After univariate analysis, determinants of progesterone concentrations were: age, weight, history of a previous cryopreserved embryo transfer with serum progesterone concentrations <10 ng/ml, and time of blood extraction. The multivariate linear regression showed that increasing age presented a positive correlation with progesterone concentrations (β = 0.11; 95% CI 0.01-0.20). On the contrary, significant negative correlations with progesterone concentrations were shown for a previous history of serum progesterone value <10 ng/ml (β = -3.13; 95% CI -4.45 to -1.81]), higher weight (β = -0.05; 95% CI -0.08 to -0.01) and the time of blood sampling during the day (β = -0.13; 95% CI -0.25 to -0.01).

CONCLUSIONS

This study adds more evidence regarding the importance of serum progesterone concentrations before frozen embryo transfer (FET). It also showed that body weight, age, time of blood sampling and a history of low progesterone are determinants associated with progesterone concentrations before blastocyst FET.

Do serum progesterone levels on day of embryo transfer influence pregnancy outcomes in artificial frozen-thaw cycles?

PURPOSE

The purpose of this study is to investigate whether progesterone (P4) levels on the day of frozen-thawed embryo transfer (FET) to a hormonally prepared endometrium correlate with pregnancy outcomes.

METHODS

This is a large retrospective cohort analysis comprising of N = 2010 FETs. In these cycles, P4 levels on the day of transfer were assessed in relation to pregnancy outcomes. A threshold of 10 ng/mL was used to simulate currently accepted levels for physiological corpus luteal function. Biochemical pregnancy, clinical pregnancy, and live birth rates were compared between those with P4 levels above and below this threshold. Analyses using transfer day P4 thresholds of 5 ng/mL and 20 ng/mL were then completed to see if these could create further prognostic power.

RESULTS

When comparing FET outcomes in relation to P4 levels < 10 ng/mL and ≥ 10 ng/mL, we observed no differences in biochemical pregnancy rates (39.53% vs. 40.98%, p = 0.52), clinical pregnancy rates (20.82 vs. 22.78, p = 0.30), and live birth rates (14.25 vs. 16.21 p = 0.23). In patients whose P4 met the threshold of 20 ng/mL, there was similarly no statistically significant improvement in pregnancy outcomes. While there was no difference for biochemical or clinical pregnancy rates, a statistically significant improvement in live birth rates was observed for those with a transfer day P4 level ≥ 5 ng/mL.

CONCLUSIONS

We demonstrated that P4 levels at or above 10 ng/mL on the day of FET do not confer a statistically significant improvement in pregnancy outcomes. P4 below 5 ng/mg was associated with lower live birth rates suggesting that there is a threshold below which it is difficult to salvage FET cycles.

Efficacy of four vaginal progesterones for luteal phase support in frozen-thawed embryo transfer cycles: A randomized clinical trial

PURPOSE

To investigate the efficacy of four vaginal progesterones, Lutinus, Utrogestan, Luteum, and Crinone, as luteal phase support (LPS) in frozen-thawed embryo transfer (Frozen-ET) cycles.

METHODS

Patients undergoing autologous Frozen-ET of one cleavage-stage embryo or one blastocyst. Two hundred fifty-nine Frozen-ET cycles were randomized to four groups for LPS: Lutinus, Utrogestan, Luteum, and Crinone. The clinical pregnancy rate (CPR), fetal heartbeat rate (FHR), and miscarriage rate (MR) were analyzed using the Mann-Whitney or Kruskal-Wallis test and Fisher exact test.

RESULTS

Two hundred thirty-five Frozen-ET cycles were analyzed: 63 cycles in the Lutinus group, 60 in the Utrogestan group, 56 in the Luteum group, and 56 in the Crinone group. No significant differences were observed between the four groups in CPR (Lutinus, Utrogestan, Luteum, and Crinone: 34.9%, 33.3%, 37.5%, and 35.7%, respectively; P = .976), FHR (26.9%, 31.6%, 30.3%, and 25.0%, respectively; P = .857), and MR (31.8%, 10.0%, 19.0%, and 30.0%, respectively; P = .306). Multivariate logistic regression analysis also revealed that there were no statistically significant differences between the four groups with regard to CPR, FHR, and MR.

CONCLUSION

There was no clinically significant difference in pregnancy outcomes between the four vaginal progesterone groups for LPS in Frozen-ET cycles.

[Progesterone and frozen-thawed embryo transfer after hormonal replacement therapy for endometrial preparation: An update on medical practices]

Frozen-thawed embryo transfer (FET) has recently become the most frequently performed ART procedure. Many protocols for endometrial preparation are used, without any evidence-based superiority of one protocol above the others. Most French fertility centers mainly use hormonal replacement treatment (HRT) for endometrial preparation for organizational reasons. According to some studies, early pregnancy losses rate is higher with HRT endometrial preparation for FET than with other protocols, leading to new insights in improving outcomes into ART centers. There is a lack of consensual guidelines regarding the use of HRT for FET: there are various protocols, with different dosages, duration and routes for progesterone (PG) prescription. To date, the vaginal route is the most popular around the world as it gives higher intra-uterine concentration of PG because of the first uterine pass. However, recent scientific publications have pointed the importance of PG measurement in order to detect a lack of PG supplementation. Whatever the route of administration, it seems that a significant proportion of patients do not reach adequate PG concentrations for successful implantation and ongoing pregnancy. Timing of the measurement and ideal serum PG rate to reach are yet to be defined. What treatment strategy to adopt according to the results is still under investigation. Individualization of PG doses and routes of administration could lead to a decrease in miscarriages and better outcome.

Pharmacokinetics of vaginal progesterone in pregnancy

BACKGROUND

Characterization of pharmacokinetics is lacking for vaginal progesterone in pregnancy. Dosing of vaginal progesterone for preterm birth prevention has been empirical. Owing to pregnancy-related changes in vaginal and uterine blood flow, hepatic metabolism, renal clearance, and endogenously elevated serum progesterone, studies outside of pregnancy may not be applicable. The lack of the pharmacokinetics profile of vaginally administered progesterone in pregnancy limits the ability to define the exposure-response relationship needed to optimize dosing, which has implications for its use in research and clinical care regarding management of short cervix, prevention of recurrent preterm birth, and prevention of recurrent miscarriage.

OBJECTIVE

This was a study to establish the feasibility of using serum progesterone to establish basic pharmacokinetic parameters of vaginal progesterone in pregnancy for preterm birth prevention.

STUDY DESIGN

This is a prospective study of 6 low-risk singletons at 18 0/7 to 23 6/7 weeks' gestation with body mass index 20-40. Exclusion criteria were current vaginitis, abnormal Pap smear, prescription medication use, cervical length ≤25 mm, prior preterm birth, and contraindication to progesterone. Participants received a single dose of 200 mg micronized vaginal progesterone and serum progesterone levels were evaluated every 2 hours from 0 to 12 hours and then 24 hours post dose. Primary outcome was concentration/time profile of serum progesterone.

RESULTS

Median (range) maternal age was 27 (21.5-33.3) years, median body mass index was 26.5 (23.3-29.0) kg/m², and median gestational age was 22.9 (21.0-23.4) weeks. Median baseline serum progesterone was 47 (40-52) ng/mL, median peak concentration was 54 (48-68) ng/mL, and median time to peak was 12 (4-15) hours. There was a trend in rising serum progesterone over baseline with a median change in peak concentration of 11 ng/mL and interquartile range of 2-22. Median percent change from baseline was an increase by 24% (interquartile range, 4%-53%). However, there was no clear elimination phase and the median area under the curve was 112 ng*h/mL with an interquartile range of -43 to 239.

CONCLUSION

Unlike in nonpregnant individuals, administration of vaginal progesterone in pregnant individuals only minimally impacts systemic exposure. There is a limited trend of rising serum progesterone over baseline levels, with significant inter-individual variability. Serum progesterone is unlikely to be a good candidate for establishing pharmacokinetics or dosing of vaginal progesterone in pregnancy for preterm birth prevention.

Towards an optimal luteal support modality in agonist triggered cycles: a randomized clinical trial

STUDY QUESTION

In ICSI patients with high risk of ovarian hyperstimulation syndrome (OHSS), are antagonist cycles triggered by gonadotropin releasing hormone (GNRH) agonist with a specialized luteal support regimen associated with comparable ongoing pregnancy rate (OPR) and less OHSS than those triggered by hCG?

SUMMARY ANSWER

In antagonist ICSI cycles, GnRH agonist triggering with a specialized luteal support regimen is associated with comparable OPR to those triggered by hCG but may be less likely to be associated with OHSS.

WHAT IS KNOWN ALREADY

In IVF/ICSI protocols, exogenous hCG was used for years as a substitute of the endogenous LH surge. However, because of its longer half life, hCG is associated with more risk of OHSS, especially in high risk women. For this reason, GnRH agonist triggering was introduced. There is, however, no consensus on the best protocol for luteal support on agonist triggered cycles.

STUDY DESIGN, SIZE, DURATION

Randomized controlled open label trial including 190 participants recruited from June 2015 to March 2016 in a private fertility center. Participants were divided into 2 equal groups; GnRH agonist trigger and hCG trigger. Randomization was done using identical sealed envelope technique.

PARTICIPANTS/MATERIALS, SETTING, METHODS

One hundred ninety women, predicted to have high response, were randomized on the day of final oocyte maturation into two equal groups: group (A), GnRH agonist trigger followed by specialized regimen (1500 IU hCG) at time of oocyte retrieval plus oral estradiol and intramuscular progesterone during luteal phase; and group (B), 5000 IU of hCG with luteal support (oral estradiol and vaginal progesterone).

MAIN RESULTS AND THE ROLE OF CHANCE

The 2 groups were comparable in baseline characteristics. OPR per randomized patient was comparable in the 2 groups {49/95 (51.6%) in group A, and 50/95 (52.6%) in group B ((P = 0.88); RR = 0.980, 95% CI: 0.75-1.29)}. Considerable (moderate + severe) OHSS was higher in group B (13/95 [14%] versus 5/95 [5%] P = 0.047; uncorrected Chi-square test). Upon performing multivariate regression analysis for predicting OHSS, number of follicles ≥11 mm on trigger day was the only independent predictor (P = 0.0004).

LIMITATIONS, REASONS FOR CAUTION

Strict selection criteria limit generalization of results. The study was powered for pregnancy rate not OHSS, so that the strength of evidence on OHSS prediction is weak.

WIDER IMPLICATIONS OF THE FINDINGS

We recommend the use of GnRH agonist plus the specialized luteal phase support in high responders with high risk of OHSS undergoing IVF/ICSI cycles. This protocol achieved a similar ongoing pregnancy to hCG triggering and may be less likely to result in moderate to severe OHSS.

STUDY FUNDING/COMPETING INTEREST(S)

None.

TRIAL REGISTRATION NUMBER

PACTR 201506001132105.

TRIAL REGISTRATION DATE

24/6/2015.

DATE OF FIRST PATIENT’S ENROLLMENT

26/6/2015.

Pharmacokinetic Properties of Three Forms of Vaginal Progesterone Administered in Either Single Or Multiple Dose Regimen in Healthy Post-menopausal Chinese Women

Objective: A generic vaginal progesterone gel has recently been developed in China. Little is known about its pharmacokinetic properties in Chinese subjects. The purpose of our study was to investigate the pharmacokinetics of three forms of vaginal progesterone gel (test formulations at 4 and 8% strength vs. a reference formulation: Crinone 8%) in Chinese healthy post-menopausal women. Methods: This study consisted of two parts study. The part 1 study was a single-center, open-label, 3-period study. Twelve healthy post-menopausal women were to evaluate the safety and pharmacokinetics of 45 mg vaginal progesterone gel (Test 4%) following single dose and multiple doses administered once every other day (q.o.d.) for six times or once daily (q.d.) for 6 days. The part 2 study was a randomized, open-label, 3-stage crossover study. Twelve post-menopausal women received 90 mg vaginal progesterone gel (Test 8%) or 90 mg Crinone (Reference 8%) following single dose and multiple doses (q.o.d. or q.d.). Plasma concentrations of progesterone were measured up to 72 h by using a validated liquid chromatography tandem-mass spectrometry method. The primary pharmacokinetic parameters, maximum plasma concentration (C_max) and area under the plasma concentration-time curve (AUC) from time zero to last measurable concentration (AUC_0-t) and extrapolated to infinity (AUC_0-∞) were compared by an analysis of variance using log-transformed data. Results: Totally 24 subjects were enrolled in and completed the study. Following single dose, The geometric mean C_max values for Test 4%, Test 8%, and Crinone 8% were 6.35, 10.34, 10.45 ng/mL, and their geometric mean AUC_0-t (AUC_0-∞) were 113.73 (118.00), 169.39 (173.98), and 190.07 (201.13) ng⋅h/mL, respectively. The mean T_1/2 values of progesterone were 11.00, 10.92, and 11.40 h, respectively. For 8% test formulation vs. reference, the 90% CIs of the least squares mean test/reference ratios of C_max, AUC_0-t, and AUC_0-∞ were 78.32-124.85%, 54.31-146.24%, and 53.64-137.75, respectively. The most frequent adverse events were increased vaginal secretions, most of which were of mild intensity and considered related to treatment. Conclusion: Results with single and multiple doses of vaginal progesterone gel suggest similar pharmacokinetics properties between test formulations and Crinone 8%. Overall, vaginal progesterone gel was well tolerated.

Progesterone supplementation for HIV-positive pregnant women on protease inhibitor-based antiretroviral regimens (the ProSPAR study): a study protocol for a pilot randomized controlled trial

Background

In Canada, the majority of HIV-positive pregnant women receive combination antiretroviral therapy that includes a ritonavir-boosted protease inhibitor to prevent mother-to-child HIV transmission. However, protease inhibitor-based combination antiretroviral therapy has been associated with increased rates of preterm, low birth weight, and small for gestational age births. Our previous experimental findings demonstrate that protease inhibitor use during pregnancy is associated with decreased progesterone levels that correlate with fetal growth, and that progesterone supplementation can improve protease inhibitor-induced fetal growth restriction. We hypothesize that HIV-positive pregnant women who receive protease inhibitor-based combination therapy may also benefit from progesterone supplementation during pregnancy.

Methods/design

In order to test this hypothesis, we have designed an open-label, multi-centre, randomized controlled (parallel group) pilot trial. The initial goal of this trial is to test feasibility and acceptability of our intervention. Forty HIV-positive pregnant women who are either on, or intending to start or switch to a boosted protease inhibitor-based combination antiretroviral regimen will be enrolled from six sites across Ontario, Canada. Twenty-five women will be randomized to self-administer natural progesterone (Prometrium, 200 mg) vaginally every night starting between gestational week 16 and 24 until week 36, and 15 women will be randomized to no intervention. While the participants and treating physicians will not be blinded, the laboratory personnel performing the biochemical and morphological evaluations will be blinded to ensure unbiased evaluation. The primary outcome of the pilot study is the feasibility of enrolment as measured by the recruitment rate and patient-reported reasons to decline participation. Secondary outcomes in participants include safety, acceptability, and adherence to progesterone supplementation.

Discussion

Given the safety of intravaginal progesterone and its current use in the general obstetrical population to prevent recurrent preterm delivery, this pilot study will provide data to determine the feasibility of a larger randomized controlled trial to assess the impact of this intervention on improving neonatal health in the context of HIV-positive pregnancies.

Trial registration

ClinicalTrials.gov, NCT02400021

Effects of exogenous progesterone on fetal nuchal translucency: an observational prospective study

OBJECTIVE

Nuchal translucency (NT) seen ultrasonographically at 11-14 weeks' gestation is a sensitive marker for Down syndrome. Despite its important role for Down syndrome screening, its use is still considered controversial due to high false-positive rates. We speculated that progesterone could lead to abnormal blood flow patterns and, subsequently, to increased NT. Our primary endpoint was to evaluate the effects of exogenous progesterone on NT thickness compared to controls. The secondary endpoint was to evaluate these effects in a subgroup at low risk for fetal aneuploidies, identifying the strongest factors influencing NT variation. The tertiary endpoint was to evaluate, within the treatment group, if there is any difference in NT according to the type of progesterone administered, route of administration, and dose regimen.

STUDY DESIGN

All women who came to measure NT at 11-14 weeks' gestation (crown-rump length between 45-84 mm) were considered eligible. We divided patients into 2 groups: women receiving exogenous progesterone and controls. Afterwards, 3 NT scans were performed for each case, and the largest value, accurate to 2 decimal points, was recorded.

RESULTS

In all, 3716 women were enrolled and analyzed. In a crude analysis, NT (P < .05) increased in the exogenous progesterone group. The same results were obtained in the low-risk group (P < .05). The factorial analysis of variance model confirmed a correlation between altered NT and gestational age (P < .0001) and progesterone exposure (P < .05). The characteristics of treatment (route, formulation, dose) were examined separately and no statistically significant differences among the subgroups were observed.

CONCLUSION

Exogenous progesterone increases NT.

A randomized comparison of the efficacy, side effects and patient convenience between vaginal and rectal administration of Cyclogest(®) when used for luteal phase support in ICSI treatment

PURPOSE

This study compares the efficacy, side effects and patient convenience of vaginal and rectal routes of administration of progesterone suppositories (Cyclogest) when used for luteal phase support during in vitro fertilization cycles, through the use of antagonist protocols.

METHODS

147 patients who underwent intra-cytoplasmic sperm injection cycle were randomized on the day of the embryo transfer (ET) by a computer-generated randomization program to receive 400 mg of Cyclogest either vaginally or rectally twice daily for up to 8 weeks. A pregnancy test was conducted 2 weeks after embryo transfer. If the pregnancy test was negative, the application was discontinued. On day 14th after embryo transfer, patient's acceptability and side effects were assessed using a questionnaire which was given to the patients on the day of ET prior to performing the pregnancy test. The clinical pregnancy rate at the 8th week of gestation and the level of luteal progesterone were evaluated.

RESULTS

There were no substantial differences in the demographics or other characteristics between the two groups. There were no significant differences in serum P concentration 6 days after ET, the clinical pregnancy and abortion rates. The difficulty of administration route, the discomforts experienced following administration, and the proportion leaking out on the 14th day were similar between the two groups. Significantly more patients administering the medication per vagina had perineal irritation (21.3 vs. 2.2 %). The prevalence of tenesmus (35.1 vs. 21.1 %) and rectal itching (26.7 vs. 2.8 %) were significantly more in rectal route.

CONCLUSIONS

This study demonstrates that the efficacy of Cyclogest is similar when administered via both the vaginal and rectal routes. Although their side effects differ, the ease of administration for patients and their preference are similar.

Single and multidose pharmacokinetic study of a vaginal micronized progesterone insert (Endometrin) compared with vaginal gel in healthy reproductive-aged female subjects

OBJECTIVE

To determine pharmacokinetic profiles of two times a day and three times a day dosage regimens of Endometrin, a micronized progesterone vaginal insert for luteal support in assisted reproductive technology, compared with a gel.

DESIGN

A single-center, randomized, open-label, single-day, and multiple-day (5 days) parallel design pharmacokinetic study.

SETTING

University clinical research unit.

PATIENT(S)

Three groups of six healthy subjects, ages 18 to 40 years.

INTERVENTION(S)

Endometrin vaginal inserts two times a day or three times a day, or gel daily.

MAIN OUTCOME MEASURE(S)

Pharmacokinetic profiles.

RESULT(S)

Progesterone serum concentrations increased rapidly following administration of Endometrin vaginal insert, producing higher peak concentrations (Cmax) and clearing faster than gel. On the single day of dosing, mean Cmax was 17.0+/-2.7 ng/mL in the two times a day group, 19.8+/-2.9 ng/mL in the three times a day group, and 6.82+/-1.69 ng/mL in the gel group. Endometrin treatments reached steady state within the first 2 days (24-36 hours), much more rapidly than the gel, which had not reached steady state by 5 days. At 5 days, the Endometrin treatments produced sustained progesterone concentrations exceeding 10 mg/mL across 24 hours.

CONCLUSIONS

Endometrin vaginal inserts reached higher Cmax, produced greater systemic exposure (area under the curve 0-24), achieved steady state more rapidly, and cleared more rapidly after termination of therapy than the comparator.

A randomized comparison of side effects and patient convenience between Cyclogest suppositories and Endometrin tablets used for luteal phase support in IVF treatment

OBJECTIVE

This study compared side effects and patient convenience of vaginal progesterone suppositories (Cyclogest) and vaginal progesterone tablets (Endometrin) used for luteal phase support in in vitro fertilization/embryo transfer (IVF/ET) cycles using pituitary downregulation.

STUDY DESIGN

One hundred and thirty-two infertile patients were randomized on the day of ET by a computer-generated randomization list in sealed envelopes to receive either Cyclogest 400mg or Endometrin 100mg twice daily for 14 days. On days 6 and 16 after ET, they rated side effects and patient convenience into four grades: none, mild, moderate and severe by completing a questionnaire.

RESULTS

No significant differences in perineal irritation were found on days 6 and 16 after ET between the two groups, although there was a trend of fewer patients with perineal irritation in the Endometrin group. Significantly more patients in the Endometrin group had difficulty of administration on day 6 after ET. There were no differences in the hormonal profile on day 6 after ET and IVF outcomes between the two groups.

CONCLUSION

There was no difference in perineal irritation after the use of Cyclogest suppositories or Endometrin tablets for luteal phase support although more patients found administration of Endometrin tablets difficult.

“Natural” progesterone: information on fetal effects

BACKGROUND

A variety of progestational agents have been used therapeutically and evaluated for adverse effects over the last 50 years. However, progesterone itself has come into use as a therapeutic agent only recently with the development of an orally bioavailable "micronized" preparation.

METHODS

The current review examines progesterone adverse effects as identified in the larger literature on the toxicity of progestational agents and pharmacokinetics.

RESULTS

Progesterone has cytoplasmic and membrane receptors in a variety of reproductive and nonreproductive tissues including the brain and is a potent inhibitor of GnRH. Limited information is available on progesterone receptors and actions in the fetus. Concern about exogenous progestagen effects on fetal reproductive tract development have led to considerable human research over the years, but this literature review demonstrates that contemporary developmental toxicology research on progesterone is lacking.

CONCLUSIONS

Progesterone is a potent, multi-faceted endocrine agent with an expanding therapeutic profile and a minimal scientific database for evaluating safe use during pregnancy.

Endometrial effects, bleeding control, and compliance with a new postmenopausal hormone therapy regimen based on transdermal estradiol gel and every-other-day vaginal progesterone in capsules: a 3-year pilot study

In a 3-year prospective study, 30 postmenopausal women received transdermal E2 gel and every-other-day vaginal P in capsules. At study completion, endometrial thickness was significantly reduced as compared with baseline (2.7 +/- 0.5 vs. 3.4 +/- 0.9 mm), endometrial biopsy showed endometrial atrophy in all cases, and amenorrhea was achieved in 92.6% of cycles, while excellent patient satisfaction was achieved.

The transport of chemicals in semen

Three mechanisms have been proposed for exposure of the conceptus to chemicals in semen: access of chemicals to the maternal circulation after absorption from the vagina, direct chemical exposure of the conceptus following transport from the vagina to the uterine cavity, and delivery to the egg and subsequent conceptus of chemical bound to the sperm cell. We review published data for each of these three mechanisms. Human seminal fluid chemical concentrations are typically similar to or lower than blood concentrations, although some antimicrobial agents achieve higher concentrations in semen than in blood. Vaginal absorption of medications has been shown to occur, although the vehicles in which these medications are delivered to the vagina may maintain contact with the vaginal epithelium to a greater extent than does semen. Assuming total absorption of a seminal dose of a chemical with a high semen:blood concentration ratio, distribution within the recipient woman would result in a blood concentration at least three orders of magnitude lower than that in the man. Direct delivery of seminal chemicals into the uterine cavity of humans has not been shown to occur, although it may occur in species such as the rat in which seminal fluid has access to the uterine cavity. Chemicals in or on human sperm cells have been demonstrated with respect to tetracycline and cocaine in vitro and aluminum, lead, and cadmium in vivo. The in vitro cocaine study offers sufficiently quantitative data with which to predict that oocyte concentrations would be five orders of magnitude lower than blood concentrations associated with cocaine abuse, assuming a maximally cocaine-bound sperm were capable of fertilizing. Thus, even using liberal assumptions about transmission of chemicals in semen or sperm, predicted exposure levels of a pregnant woman or of the conceptus are three or more orders of magnitude lower than blood concentrations in the man whose semen is the putative vehicle for chemical transport.

A randomised comparison of side effects and patient inconvenience of two vaginal progesterone formulations used for luteal support in in vitro fertilisation cycles

OBJECTIVE

To compare side effects and patient inconvenience of two vaginal progesterone (P) formulations for luteal support in in vitro fertilisation cycles.

STUDY DESIGN

Sixty infertile patients at risk of developing ovarian hyperstimulation syndrome were randomised to receive either Cyclogest vaginal suppositories 400mg twice daily or Crinone 8% vaginal gel once daily for 14 days as the luteal support. On Day 6 and Day 16 after embryo transfer, they rated side effects and patient inconvenience into four grades: none, mild, moderate and severe by completing a questionnaire.

RESULTS

Perineal irritation was reported by about 20% of patients in each group. Significantly more patients using Cyclogest suppositories graded inconvenience of administration, leaking out and interference with coitus as moderate or severe.

CONCLUSION

There was no difference in perineal irritation after Cyclogest suppositories or Crinone 8% gel although significantly more patients found inconvenience of administration, leaking out and interference with coitus after Cyclogest.

Pharmacokinetics of progesterone in postmenopausal women: 2. Pharmacokinetics following percutaneous administration

Progesterone was administered percutaneously to postmenopausal women in topical applications on the breast and chest areas in a hydrophilic (gel), lipophilic and an emulsion type base. Venous blood samples were taken 2, 4, 6, 24, 48 and 72 h following administration. The plasma levels were evaluated by radioimmunoassay. Time of maximum concentration (tmax) was, in all cases, in the neighborhood of 4 h. Mean peak plasma concentrations were: 1 ng/ml for the lipophilic, 1.24 ng/ml for the hydrophilic and 2.26 ng/ml for the emulsion type base. The areas under the curves (AUCs) were practically equivalent for the first two methods, but higher values were obtained for administration in the emulsion type base. The elimination was slow, with a half-time varying in the range of 3040 h for all three types of base, a value that was much higher than those obtained after administration of progesterone via vaginal suppositories. The AUCs were parallel with the peak plasma concentrations: almost 2-fold higher for emulsion than for the gel and lipophilic base. Fit for plasma levels using mono-, bi- and tricompartmental models furnished acceptable results only in the case of monocompartmental model, which raises a number of physiological and physico-chemical considerations. A 'pseudomonocompartmental' model was constructed to explain this 'anomaly'.

Pharmacokinetics of progesterone in postmenopausal women: 1. Pharmacokinetics following intravaginal administration

Progesterone was administered to postmenopausal women in a form of vaginal suppositories containing 100 and 200 mg active substance in Butyrum cacao (BC) and Massa estarinum (ME), a base with emulsifying properties. In the case of single doses, blood samples were taken at 2, 4, 6, 24, 48 and 72 h. Another group of patients received vaginal suppositories (100 mg progesterone) once a day for a 6 day period, with blood samples taken 12 h after each administration. The plasma levels of progesterone were evaluated by radioimmunoassay. The time of maximum concentration (tmax) was 4 h in most cases, and 6 h in the others. The plasma levels were not dose-proportional. Peak plasma concentrations were in the range of 10-15 ng/ml with a mean of 10.5 ng/ml for the 100 mg and 12 ng/ml for the 200 mg doses. The ratio of the mean area under the curve (AUC) for 200 mg and the mean AUC for the 100 mg dose was found to be 1.37. Replacing BC with ME resulted in the lowering of cmax and AUC, and an increase in tmax following a reducing in the rate and extent of adsorption. In the case of ME suppositories, the variability in AUC, cmax and tmax was greater compared to that observed with the BC suppositories. Elimination half-time was in the range of 9-10 h for BC and 14 h for ME suppositories. In vitro assessment of the release kinetics from a hydrophobic and an emulsion type base confirmed previous findings: the latter base assured better pharmaceutical availability. The repeated doses did not seem to produce an accumulation of progesterone in the plasma. On the contrary, a small decrease in plasma levels over time appeared during the 6 day period. Numerical analysis revealed an excellent goodness of fit for the in vivo experimental data via biexponential curves, i.e. a pseudomonocompartmental model.

Comparative permeability of human vaginal and buccal mucosa to water

There is currently a resurgence of interest in the oral mucosa as a route for drug delivery. The relative scarcity of human oral mucosa for in vitro permeability studies, and the fact that vaginal mucosa is histologically similar and more abundant than the former, caused us to compare these 2 tissues with respect to their barrier properties to water. Specimens of fresh, clinically-healthy human vaginal and buccal mucosa from non-smokers were taken from excised tissue obtained during vaginal hysterectomies and various oral surgical procedures. Biopsies from each specimen were mounted in flow-through diffusion cells and their permeability to tritiated water determined using a continuous flow-through perfusion system. Specimens were examined histologically before and after permeability experiments and similarities between vaginal and buccal tissues verified. No statistically significant differences between mean steady state flux values (10-16 h) for vaginal and buccal mucosa, respectively, were found. Human vaginal mucosa is therefore as permeable as buccal mucosa to water, and these results warrant further investigation with other compounds to establish whether vaginal mucosa may be a useful model for buccal mucosa for drug permeability studies.

17alpha-Dihydroequilenin increases hippocampal dendritic spine density of ovariectomized rats

The effects of estradiol and 17alpha-dihydroequilenin on the apical dendrite spine density of pyramidal cells of the CA1 region of rat hippocampus were compared. 17alpha-Dihydroequilenin was as effective as estradiol in increasing spine densities relative to controls. 17alpha-Dihydroequilenin is not uterotrophic like estradiol but does have beneficial effects on the cardiovascular system, suggesting that it may be an effective single-agent hormone replacement therapy to treat menopausal symptoms and reduce chronic disease risk in menopausal women.

Transdermal estrogen with a levonorgestrel-releasing intrauterine device for climacteric complaints versus estradiol-releasing vaginal ring with a vaginal progesterone suppository: clinical and endometrial responses

OBJECTIVE

Our purpose was to compare the effects of a new estradiol-releasing vaginal ring with progesterone given as a vaginal suppository, versus the efficacy, safety and acceptability of an intrauterine device releasing levonorgestrel combined with estradiol, delivered transdermally from a patch. Climacteric symptoms, bleeding pattern and endometrial histologic features were studied.

METHODS

Fifty six parous, postmenopausal women with urogenital symptoms were allocated in two groups for one year: 28 women receiving estradiol by a vaginal ring and a 100 mg vaginal progesterone suppository 7 days every month and 28 women receiving a continuous transdermal daily dose of 50 micrograms of estradiol with a levonorgestrel-releasing intrauterine device inserted. All the patients were subjected to vaginosonographic examination followed by thorough pathological examination of the uterine curetting samples.

RESULTS

A mean endometrial thickness (double layer) of 2.9 and 3.0 mm, respectively, was found to be predictive of normal endometrium. Both treatment regiments effectively relieved climacteric symptoms. Endometrial proliferation was not observed. Spotting was more common in the intrauterine device group than in the vaginal ring group.

CONCLUSIONS

Treatment of urogenital symptoms in postmenopausal women with these two forms of hormone replacement therapy is shown to be an effective and safe method, exhibiting advantages over other methods of treatment.