Short versus extended progesterone supplementation for luteal phase support in fresh IVF cycles: a systematic review and meta-analysis

Comparison of luteal support protocols in fresh IVF/ICSI cycles: a network meta-analysis

Despite the proven superiority of various luteal phase support protocols (LPS) over placebo in view of improved pregnancy rates in fresh cycles of IVF (in vitro fertilization) and ICSI (intracytoplasmic sperm injection) cycles, there is ongoing controversy over specific LPS protocol selection, dosage, and duration. The aim of the present study was to identify the optimal LPS under six core aspects of ART success, clinical pregnancy, live birth as primary outcomes and biochemical pregnancy, miscarriage, multiple pregnancy, ovarian hyperstimulation syndrome (OHSS) events as secondary outcomes. Twelve databases, namely Embase (OVID), MEDLINE (R) (OVID), GlobalHealth (Archive), GlobalHealth, Health and Psychosocial Instruments, Maternity & Infant Care Database (MIDIRS), APA PsycTests, ClinicalTrials.gov, HMIC Health Management Information Consortium, CENTRAL, Web of Science, Scopus and two prospective registers, MedRxiv, Research Square were searched from inception to Aug.1st, 2023, (PROSPERO Registration: CRD42022358986). Only Randomised Controlled Trials (RCTs) were included. Bayesian network meta-analysis (NMA) model was employed for outcome analysis, presenting fixed effects, odds ratios (ORs) with 95% credibility intervals (CrIs). Vaginal Progesterone (VP) was considered the reference LPS given its' clinical relevance. Seventy-six RCTs, comparing 22 interventions, and including 26,536 participants were included in the present NMA. Overall CiNeMa risk of bias was deemed moderate, and network inconsistency per outcome was deemed low (Multiple pregnancy χ2: 0.11, OHSS χ2: 0.26), moderate (Clinical Pregnancy: χ2: 7.02, Live birth χ2: 10.95, Biochemical pregnancy: χ2: 6.60, Miscarriage: χ2: 11.305). Combinatorial regimens, with subcutaneous GnRH-a (SCGnRH-a) on a vaginal progesterone base and oral oestrogen (OE) appeared to overall improve clinical pregnancy events; VP + OE + SCGnRH-a [OR 1.57 (95% CrI 1.11 to 2.22)], VP + SCGnRH-a [OR 1.28 (95% CrI 1.05 to 1.55)] as well as live pregnancy events, VP + OE + SCGnRH-a [OR 8.81 (95% CrI 2.35 to 39.1)], VP + SCGnRH-a [OR 1.76 (95% CrI 1.45 to 2.15)]. Equally, the progesterone free LPS, intramuscular human chorionic gonadotrophin, [OR 9.67 (95% CrI 2.34, 73.2)] was also found to increase live birth events, however was also associated with an increased probability of ovarian hyperstimulation, [OR 1.64 (95% CrI 0.75, 3.71)]. The combination of intramuscular and vaginal progesterone was associated with higher multiple pregnancy events, [OR 7.09 (95% CrI 2.49, 31.)]. Of all LPS protocols, VP + SC GnRH-a was found to significantly reduce miscarriage events, OR 0.54 (95% CrI 0.37 to 0.80). Subgroup analysis according to ovarian stimulation (OS) protocol revealed that the optimal LPS across both long and short OS, taking into account increase in live birth and reduction in miscarriage as well as OHSS events, was VP + SCGnRH-a, with an OR 2.89 [95% CrI 1.08, 2.96] and OR 2.84 [95% CrI 1.35, 6.26] respectively. Overall, NMA data suggest that combinatorial treatments, with the addition of SCGnRH-a on a VP base result in improved clinical pregnancy and live birth events in both GnRH-agonist and antagonist ovarian stimulation protocols.

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.

Diagnosis and management of infertility: NICE-adapted guidelines from the Italian Society of Human Reproduction

In Italy the fertility rate is very low, and an increasing number of patients are infertile and require treatments. The Italian Law concerning the safety of patient care, and the professional liability of health professionals, indicates that health professionals must comply with the recommendations set out in the guidelines developed by public and private bodies and institutions, as well as scientific societies and technical-scientific associations of the health professions, except for specific cases. Unfortunately, no guideline for the diagnosis and the management of infertility is currently available in Italy. In 2019, the Italian Society of Human Reproduction pointed out the need to produce Italian guidelines and subsequently approved the establishment of a multidisciplinary and multiprofessional working group (MMWG) to develop such a guideline. The MMWG was representative of 5 scientific societies, one national federation of professional orders, 3 citizens' and patients' associations, 5 professions (including lawyer, biologist, doctor, midwife, and psychologist), and 3 medical specialties (including medical genetics, obstetrics and gynecology, and urology). The MMWG chose to adapt a high-quality guideline to the Italian context instead of developing one from scratch. Using the Italian version of the Appraisal of Guidelines for Research and Evaluation II scoring system, the National Institute of Clinical Excellence guidelines were selected and adapted to the Italian context. The document was improved upon by incorporating comments and suggestions where needed. This study presents the process of adaptation and discusses the pros and cons of the often-neglected choice of adapting rather than developing new guidelines.

Serum progesterone level in luteal phase improves pregnancy rate in fresh cycles with blastocyst embryo transfer

OBJECTIVE

To assess the association between serum level of progesterone during stimulation and in the luteal phase with pregnancy rate in a cohort of patients undergoing in vitro fertilization and embryo transfer (IVF-ET) on day 5.

METHODS

Retrospective Cohort Study. Patients: 62 infertile women, aged 24-42 years, undergoing ART at our center from May 2019 to May 2021. Progesterone was evaluated during ovarian stimulation on Day 2, Day 6, and Day 8 of stimulation, day of trigger (P4dhCG), and on the day of blastocyst transfer with 5 days of progesterone supplementation (P4d5+). We also calculated the difference of P4d5+ with P4dhCG. (∆P4). Then we divided the patients into two groups based on progesterone serum levels at P4d5+; <10ng/ml (Group A), ≥10ng/ml (Group B). The Student's t-test was performed for continuous variables; Mann-Whitney's Test and Spearman's Test were used where appropriate for categorical variables. p<0.05 was considered statistically significant.

RESULTS

There were positive correlations between βhCG positive with P4d5+ (p<0.001; Rho 0.770) and ∆P4 (p<0.001; Rho 0.703). The pregnancy rate doubled when the serum progesterone level was ≥10ng/ml on the fifth day of progesterone supplementation compared with P4<10ng/ml (44% vs. 21%, respectively).

CONCLUSIONS

The pregnancy rate was positively correlated with the serum P4 level on the fifth day of progesterone supplementation and with the difference between the serum progesterone level in the Dd5+ / dhCG. A higher pregnancy rate was observed when serum progesterone level on the fifth day of progesterone supplementation was ≥10ng/ml.

The Impact of Suppressing Estradiol During Ovarian Stimulation on the Unsupported Luteal Phase: A Randomized Controlled Trial

CONTEXT

Supraphysiological sex steroid levels at the follicular-luteal phase transition are implicated as the primary cause of luteal insufficiency after ovarian stimulation (OS) for in vitro fertilization.

OBJECTIVE

We aimed to determine the impact of suppressing estradiol levels during OS of multiple dominant follicles on the unsupported luteal phase and markers of endometrial maturation.

METHODS

At 2 university hospitals, 25 eligible egg donors were randomized to undergo OS using exogenous gonadotropins with or without adjuvant letrozole 5 mg/day. Final oocyte maturation was triggered with a GnRH agonist. No luteal support was provided. The primary outcome was the duration of the luteal phase. Secondary outcomes were luteal phase hormone profiles and the endometrial transcriptomic signature 5 days after oocyte pick up (OPU + 5).

RESULTS

The median (interquartile range [IQR]) luteal phase duration was 8.0 (6.8-11.5) days compared with 5.0 (5.0-6.8) days in the intervention and control group, respectively (P < 0.001). Estradiol levels were effectively suppressed in the letrozole group with a median of 0.86 (0.23-1.24) nmol/L at OPU compared to 2.82 (1.34-3.44) nmol/L in the control group. Median (IQR) progesterone levels at OPU + 5 were 67.05 (15.67-101.75) nmol/L in the letrozole group vs 2.27 (1.05-10.70) nmol/L in the control group (P < 0.001). In the letrozole group, 75% of participants revealed endometrial transcriptomic signatures interpreted as post-receptive. In the control group, 40% were post-receptive and 50% noninformative.

CONCLUSION

Suppressing estradiol levels in the follicular phase with adjuvant letrozole significantly reduces the disruption of the unsupported luteal phase after OS.

GnRH agonist as a luteal support in IVF cycle: mini-review—is there a role?

Background

It has been established that assisted reproductive technology (ART) cycles are usually accompanied by a defective luteal phase, and that luteal phase support (LPS) is mandatory to improve reproductive outcomes. This review aims to summarize the hypothesis, safety and current evidence about GnRH agonist as a luteal phase support in ART.

Main body

There are many regimens of luteal phase support to improve ART outcomes in women undergoing fresh and thawed cycles. Luteal phase support drugs include progesterone, human chorionic gonadotropin, gonadotropin-releasing hormone agonist, estradiol, and recombinant luteinizing hormone. There is some debate about optimal drugs and timing for start of LPS in ART cycles.

Conclusion

Although most centers support luteal phase by vaginal progesterone, GnRH agonist is a debatable drug for luteal support cycles.

Evaluating interventions and adjuncts to optimize pregnancy outcomes in subfertile women: an overview review

BACKGROUND

There is a wealth of information regarding interventions for treating subfertility. The majority of studies exploring interventions for improving conception rates also report on pregnancy outcomes. However, there is no efficient way for clinicians, researchers, funding organizations, decision-making bodies or women themselves to easily access and review the evidence for the effect of adjuvant therapies on key pregnancy outcomes in subfertile women.

OBJECTIVE AND RATIONALE

The aim was to summarize all published systematic reviews (SRs) of randomized controlled trials (RCTs) of interventions in the subfertile population, specifically reporting on the pregnancy outcomes of miscarriage and live birth. Furthermore, we aimed to highlight promising interventions and areas that need high-quality evidence.

SEARCH METHODS

We searched the Cochrane Database of Systematic Reviews and PubMed clinical queries SR filter (inception until July 2021) with a list of key words to capture all SRs specifying or reporting any miscarriage outcome. Studies were included if they were SRs of RCTs. The population was subfertile women (pregnant or trying to conceive) and any intervention (versus placebo or no treatment) was included. We adopted Grading of Recommendations, Assessment, Development and Evaluation (GRADE) for determining the quality of the evidence. Exclusion criteria were overview reviews, reviews that exclusively reported on women conceiving via natural conception, reviews including non-randomized study designs or reviews where miscarriage or live birth outcomes were not specified or reported.

OUTCOMES

The primary outcome was miscarriage, defined as pregnancy loss <24 weeks of gestation. Data were also extracted for live birth where available. We included 75 published SRs containing 121 251 participants. There were 14 classes of intervention identified: luteal phase, immunotherapy, anticoagulants, hCG, micronutrients, lifestyle, endocrine, surgical, pre-implantation genetic testing for aneuploidies (PGT-As), laboratory techniques, endometrial injury, ART protocols, other adjuncts/techniques in the ART process and complementary interventions. The interventions with at least moderate-quality evidence of benefit in reducing risk of miscarriage or improving the chance of a live birth are: intrauterine hCG at time of cleavage stage embryo transfer, but not blastocyst transfer, antioxidant therapy in males, dehydroepiandrosterone in women and embryo medium containing high hyaluronic acid. Interventions showing potential increased risk of miscarriage or reduced live birth rate are: embryo culture supernatant injection before embryo transfer in frozen cycles and PGT-A with the use of fluorescence in situ hybridization.

WIDER IMPLICATIONS

This review provides an overview of key pregnancy outcomes from published SRs of RCTs in subfertile women. It provides access to concisely summarized information and will help clinicians and policy makers identify knowledge gaps in the field, whilst covering a broad range of topics, to help improve pregnancy outcomes for subfertile couples. Further research is required into the following promising interventions: the dose of progesterone for luteal phase support, peripheral blood mononuclear cells for women with recurrent implantation failure, glucocorticoids in women undergoing IVF, low-molecular-weight heparin for unexplained subfertility, intrauterine hCG at the time of cleavage stage embryo or blastocyst transfer and low oxygen concentrations in embryo culture. In addition, there is a need for high-quality, well-designed RCTs in the field of reproductive surgery. Finally, further research is needed to demonstrate the integrated effects of non-pharmacological lifestyle interventions.

The efficacy and safety of luteal phase support with progesterone following ovarian stimulation and intrauterine insemination: A systematic review and meta-analysis

The aim of this systematic review and meta-analysis was to update the current evidence for the efficacy and safety of progesterone luteal phase support (LPS) following ovarian stimulation and intrauterine insemination treatment (OS-IUI) for unexplained or mild male infertility. Four additional studies were identified compared to the previous review in 2017. Twelve RCTs (2631 patients, 3262 cycles) met full inclusion criteria. Results from quantitative synthesis suggest that progesterone LPS after OS-IUI leads to higher live birth (RR 1.38, 95%CI [1.09, 1.74]; 7 RCTs, n=1748) and clinical pregnancy rates (RR 1.38, 95% CI [1.21, 1.59]; 11 RCTs, n=2163) than no LPS or placebo. This effect is specifically present in protocols using gonadotropins for OS-IUI (RR 1.41, 95%CI [1.17, 1.71]; 7 RCTs, n=1114), and unclear in protocols involving clomiphene citrate (RR 1.01, 95% CI [0.05, 18.94]; 2 RCTs, n=138). We found no effect of progesterone LPS on multiple pregnancy or miscarriage rates. No correlation between drug-dosage or duration of treatment and effect size was seen. Though our results suggest both benefit and safety of progesterone LPS in OS-IUI, evidence is of low to moderate quality and additional well-powered trials are still mandatory to confirm our findings and justify implementation in daily practice.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=292325, identifier CRD42021292325.

Luteal-phase support in assisted reproductive technology: An ongoing challenge

It has been shown that in controlled ovarian hyper stimulation cycles, defective luteal phase is common. There are many protocols for improving pregnancy outcomes in women undergoing fresh and frozen in vitro fertilization cycles. These approaches include progesterone supplements, human chorionic gonadotropin, estradiol, gonadotropin-releasing hormone agonist, and recombinant luteinizing hormone. The main challenge is luteal-phase support (LPS) in cycles with gonadotropin-releasing hormone agonist triggering. There is still controversy about the optimal component and time for starting LPS in assisted reproductive technology cycles. This review aims to summarize the various protocols suggested for LPS in in vitro fertilization cycles.

Serum luteal phase progesterone in women undergoing frozen embryo transfer in assisted conception: a systematic review and meta-analysis

OBJECTIVE

To investigate the association between luteal serum progesterone levels and frozen embryo transfer (FET) outcomes.

DESIGN

Systematic review and meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Women undergoing FET.

INTERVENTION(S)

We conducted electronic searches of MEDLINE, PubMed, CINAHL, EMBASE, the Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Web of Science, ClinicalTrials.gov, and grey literature (not widely available) from inception to March 2021 to identify cohort studies in which the serum luteal progesterone level was measured around the time of FET.

MAIN OUTCOME MEASURE(S)

Ongoing pregnancy or live birth rate, clinical pregnancy rate, and miscarriage rate.

RESULT(S)

Among the studies analyzing serum progesterone level thresholds <10 ng/mL, a higher serum progesterone level was associated with increased rates of ongoing pregnancy or live birth (relative risk [RR] 1.47, 95% confidence interval [CI] 1.28 to 1.70), higher chance of clinical pregnancy (RR 1.31, 95% CI 1.16 to 1.49), and lower risk of miscarriage (RR 0.62, 95% CI 0.50 to 0.77) in cycles using exclusively vaginal progesterone and blastocyst embryos. There was uncertainty about whether progesterone thresholds ≥10 ng/mL were associated with FET outcomes in sensitivity analyses including all studies, owing to high interstudy heterogeneity and wide CIs.

CONCLUSION(S)

Our findings indicate that there may be a minimum clinically important luteal serum concentration of progesterone required to ensure an optimal endocrine milieu during embryo implantation and early pregnancy after FET treatment. Future clinical trials are required to assess whether administering higher-dose luteal phase support improves outcomes in women with a low serum progesterone level at the time of FET.

PROSPERO NUMBER

CRD42019157071.

What is the optimal luteal support in assisted reproductive technology?

The need for luteal phase support in IVF/ICSI is well established. A large effort has been made in the attempt to identify the optimal type, start, route, dosage and duration of luteal phase support for IVF/ICSI and frozen embryo transfer. These questions are further complicated by the different types of stimulation protocols and ovulation triggers used in ART. The aim of this review is to supply a comprehensive overview of the available types of luteal phase support, and the indications for their use.A review of the literature was carried out in the effort to find the optimal luteal phase support regimen with regards to pregnancy related outcomes and short and long term safety.The results demonstrate that vaginal, intramuscular, subcutaneous and rectal progesterone are equally effective as luteal phase support in IVF/ICSI. GnRH agonists and oral dydrogesterone are new and promising treatment modalities but more research is needed. hCG and estradiol are not recommended for luteal phase support. More research is needed to establish the most optimal luteal phase support in frozen embryo transfer cycles, but progesterone has been shown to improve live birth rate in some studies. Luteal phase support should be commenced between the evening of the day of oocyte retrieval, and day three after oocyte retrieval and it should be continued at least until the day of positive pregnancy test.So, in conclusion still more large and well-designed RCT's are needed to establish the most optimal luteal phase support in each stimulation protocol, and especially in frozen embryo transfer.

"All-In-One" Genetic Tool Assessing Endometrial Receptivity for Personalized Screening of Female Sex Steroid Hormones

Endometrium is the uterine lining that undergoes hundreds of cycles of proliferation, differentiation, and desquamation throughout a woman's reproductive life. Recently, much attention is paid to the appropriate endometrial functioning, as decreased endometrial receptivity is stated to be one of the concerns heavily influencing successes of embryo implantation rates and the efficacy of in vitro fertilization (IVF) treatment. In order to acquire and maintain the desired endometrial receptivity during IVF cycles, luteal phase support by various progestagens or other hormonal combinations is generally recommended. However, today, the selection of the specific hormonal therapy during IVF seems to be empirical, mainly due to a lack of appropriate tools for personalized approach. Here, we designed the genetic tool for patient-specific optimization of hormonal supplementation schemes required for the maintenance of endometrial receptivity during luteal phase. We optimized and characterized in vitro endometrial stromal cell (ESC) decidualization model as the adequate physiological reflection of endometrial sensitivity to steroid hormones. Based on the whole transcriptome RNA sequencing and the corresponding bioinformatics, we proposed that activation of the decidual prolactin (PRL) promoter containing ancient transposons MER20 and MER39 may reflect functioning of the core decidual regulatory network. Furthermore, we cloned the sequence of decidual PRL promoter containing MER20 and part of MER39 into the expression vector to estimate the effectiveness of ESC decidual response and verified sensitivity of the designed system. We additionally confirmed specificity of the generated tool using human diploid fibroblasts and adipose-derived human mesenchymal stem cells. Finally, we demonstrated the possibility to apply our tool for personalized hormone screening by comparing the effects of natural progesterone and three synthetic analogs (medroxyprogesterone 17-acetate, 17α-hydroxyprogesterone caproate, dydrogesterone) on decidualization of six ESC lines obtained from patients planning to undergo the IVF procedure. To sum up, we developed the "all-in-one" genetic tool based on the MER20/MER39 expression cassette that provides the ability to predict the most appropriate hormonal cocktail for endometrial receptivity maintenance specifically and safely for the patient, and thus to define the personal treatment strategy prior to the IVF procedure.

A 10-year follow-up on the practice of luteal phase support using worldwide web-based surveys

BACKGROUND

It has been demonstrated that luteal phase support (LPS) is crucial in filling the gap between the disappearance of exogenously administered hCG for ovulation triggering and the initiation of secretion of endogenous hCG from the implanting conceptus. LPS has a pivotal role of in establishing and maintaining in vitro fertilization (IVF) pregnancies. Over the last decade, a plethora of studies bringing new information on many aspects of LPS have been published. Due to lack of consent between researchers and a dearth of robust evidence-based guidelines, we wanted to make the leap from the bench to the bedside, what are the common LPS practices in fresh IVF cycles compared to current evidence and guidelines? How has expert opinion changed over 10 years in light of recent literature?

METHODS

Over a decade (2009-2019), we conducted 4 web-based surveys on a large IVF-specialist website on common LPS practices and controversies. The self-report, multiple-choice surveys quantified results by annual IVF cycles.

RESULTS

On average, 303 IVF units responded to each survey, representing, on average, 231,000 annual IVF cycles. Most respondents in 2019 initiated LPS on the day of, or the day after egg collection (48.7 % and 36.3 %, respectively). In 2018, 72 % of respondents administered LPS for 8-10 gestational weeks, while in 2019, 65 % continued LPS until 10-12 weeks. Vaginal progesterone is the predominant delivery route; its utilization rose from 64 % of cycles in 2009 to 74.1 % in 2019. Oral P use has remained negligible; a slight increase to 2.9 % in 2019 likely reflects dydrogesterone's introduction into practice. E2 and GnRH agonists are rarely used for LPS, as is hCG alone, limited by its associated risk of ovarian hyperstimulation syndrome (OHSS).

CONCLUSIONS

Our Assisted reproductive technology (ART)-community survey series gave us insights into physician views on using progesterone for LPS. Despite extensive research and numerous publications, evidence quality and recommendation levels are surprisingly low for most topics. Clinical guidelines use mostly low-quality evidence. There is no single accepted LPS protocol. Our study highlights the gaps between science and practice and the need for further LPS research, with an emphasis on treatment individualization.

Early pregnancy maternal progesterone administration alters pituitary and testis function and steroid profile in male fetuses

Maternal exposure to increased steroid hormones, including estrogens, androgens or glucocorticoids during pregnancy results in chronic conditions in offspring that manifest in adulthood. Little is known about effects of progesterone administration in early pregnancy on fetal development. We hypothesised that maternal early pregnancy progesterone supplementation would increase fetal progesterone, affect progesterone target tissues in the developing fetal reproductive system and be metabolised to other bioactive steroids in the fetus. We investigated the effects of progesterone treatment during early pregnancy on maternal and fetal plasma progesterone concentrations, transcript abundance in the fetal pituitary and testes and circulating steroids, at day 75 gestation, using a clinically realistic ovine model. Endogenous progesterone concentrations were lower in male than female fetuses. Maternal progesterone administration increased male, but not female, fetal progesterone concentrations, also increasing circulating 11-dehydrocorticosterone in male fetuses. Maternal progesterone administration altered fetal pituitary and testicular function in ovine male fetuses. This suggests that there may be fetal sex specific effects of the use of progesterone in early pregnancy, and highlights that progesterone supplementation should be used only when there is clear evidence of efficacy and for as limited time as necessary.

When Can We Safely Stop Luteal Phase Support in Fresh IVF Cycles? A Literature Review

There is no consensus on the optimal duration of luteal phase support (LPS) in fresh IVF cycles. Although some clinicians withdraw LPS on the day of a positive pregnancy test, most clinicians continue its administration at least up to the 8th week of gestation. In this literature review, we included several randomized clinical trials comparing early and late cessation of LPS. Most studies have found no benefit in extended administration. These studies, however, were limited by their small sample size and selection bias. Until now, only a few attempts have been made to indicate when LPS can be safely stopped based on individual patient characteristics. In conclusion, the quality and quantity of the evidence regarding LPS duration in fresh IVF cycles is currently insufficient to justify early cessation in all patients. Individualization of LPS should receive high priority in future research.

Luteal Phase Support in IVF: Comparison Between Evidence-Based Medicine and Real-Life Practices

Background: Luteal phase support (LPS) in assisted reproduction cycles has been widely investigated in recent years. Although progesterone represents the preferential product for luteal phase supplementation in cycles with fresh embryo transfer, there is ongoing debate as to when to start, which is the best route, dosage and duration, and whether there is a place for additional agents. Nevertheless, fertility specialists do not always adhere to evidence-based recommendations in their clinical practice. The aim of this worldwide web-based survey is to document the currently used protocols for luteal phase support and appraisal tendencies of drug prescription behavior and to compare these to the existing evidence-based literature. Material and Methods: A questionnaire was developed and sent by secure e-mail to 1,480 clinicians involved in ART worldwide. One hundred and forty-eighth clinicians from 34 countries returned completed questionnaires. Results: Progesterone support is usually started on the day of oocyte retrieval. Eighty percent of clinicians applied the administration of vaginal progesterone only. Intramuscular progesterone was prescribed by 6%, while oral progestin or subcutaneous progesterone were each prescribed by 5% of clinicians, respectively. Progesterone was administered until 8-10 weeks' gestation by 35% and 12 weeks by 52% of respondents. Conclusions: Vaginal administration was the preferred route for luteal phase support. The reported emerging use of the oral route confirms the expected shift in clinical practice as a result of recent evidence showing a reassuring safety score of oral progestins. In spite of the lack of evidence supporting the continuation of luteal support until 12 weeks' gestation, this practice was adhered to by more than half of the clinicians surveyed, highlighting the difference between evidence-based medicine and real-life practices.