Luteal phase support with progesterone in intrauterine insemination: a prospective randomized study

Optimizing intrauterine insemination: A systematic review and meta-analysis of the effectiveness and safety of clinical treatment add-ons

INTRODUCTION

Intrauterine insemination (IUI) is one of the most widespread fertility treatments. However, IUI protocols vary significantly amongst fertility clinics. Various add-on interventions have been proposed to boost success rates. These are mostly chosen arbitrarily or empirically. The aim of this systematic review and meta-analysis is to assess the effectiveness and safety of add-on interventions to the standard IUI protocol and to provide evidence-based recommendations on techniques used to optimize the clinical outcomes of IUI treatment.

MATERIAL AND METHODS

Systematic review and meta-analyses were performed in accordance with PRISMA guidelines. A computerized literature search was performed from database inception to May 2023. Randomized controlled trials (RCTs) were included reporting on couples/single women undergoing IUI with any protocol for any indication using partner's or donor sperm. A meta-analysis based on random effects was performed for each outcome and add-on. Three authors independently assessed the trials for quality and risk of bias and overall certainty of evidence. Uncertainties were resolved through consensus. Primary outcomes were ongoing pregnancy rate (OPR) or live birth rate (LBR) per cycle/per woman randomized. Registration number PROSPERO: CRD42022300857.

RESULTS

Sixty-six RCTs were included in the analysis (16 305 participants across 20 countries). Vaginal progesterone as luteal phase support in stimulated cycles was found to significantly increase LBR/OPR (RR 1.37, 95% CI 1.09-1.72, I2 = 4.9%) (moderate/low certainty of the evidence). Endometrial scratch prior/during stimulated IUI cycles may increase LBR/OPR (RR 1.44, 95% CI 1.03-2.01, I2 = 1.8%), but evidence is very uncertain. Results from two studies suggest that follicular phase ovarian stimulation increases LBR/OPR (RR 1.39, 95% CI 1.00-1.94, I2 = 0%) (low certainty of evidence). No significant difference was seen for the primary outcome for the other studied interventions.

CONCLUSIONS

The findings of this systematic review and meta-analysis suggest that vaginal luteal phase progesterone support probably improves LBR/OPR in stimulated IUI treatments. In view of moderate/low certainty of the evidence more research is needed for solid conclusions. Further research is also recommended for the use of endometrial scratch and ovarian stimulation. Future studies should report on results according to subfertility background as it is possible that different add-ons could benefit specific patient groups.

Hotspots and frontiers in luteal phase defect research: An in-depth global trend bibliometric and visualization analysis over a 52-year period

Luteal phase defect (LPD) is a common female reproductive endocrine defect，which is associated not only with certain diseases but also with the menstrual cycle and fertility in women. With the development of assisted reproductive technology (ART) in recent years, the incidence of luteal phase defect is high among patients using assisted reproductive technology. The aim of this study was to evaluate worldwide research on luteal phase defects using bibliometric analysis. A total of 631 documents related to the study of luteal phase defect were identified over the last 52 years. The current status and trend of globalization can be comprehended by analyzing the annual number of publications, institutions, authors, countries and regions of corresponding authors, journals, influential luteal phase defect publications (which were highly cited), highly cited references in luteal phase defect publications (cocitation analysis) and keywords. The study results provide a comprehensive overview of the development of scientific literature and are of great significance for the future development of the field，especially infertility and early pregnancy loss.

Luteal phase support for women trying to conceive by intrauterine insemination or sexual intercourse

BACKGROUND

Ovulation induction may impact endometrial receptivity due to insufficient progesterone secretion. Low progesterone is associated with poor pregnancy outcomes.

OBJECTIVES

To assess the effectiveness and safety of luteal phase support (LPS) in infertile women trying to conceive by intrauterine insemination or by sexual intercourse.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Group Specialised Register, CENTRAL, MEDLINE, Embase, PsycINFO, LILACS, trial registries for ongoing trials, and reference lists of articles (from inception to 25 August 2021).

SELECTION CRITERIA

Randomised controlled trials (RCTs) of LPS using progestogen, human chorionic gonadotropin (hCG), or gonadotropin-releasing hormone (GnRH) agonist supplementation in IUI or natural cycle.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were live birth rate/ongoing pregnancy rate (LBR/OPR) and miscarriage.  MAIN RESULTS: We included 25 RCTs (5111 participants). Most studies were at unclear or high risk of bias. We graded the certainty of evidence as very low to low. The main limitations of the evidence were poor reporting and imprecision. 1. Progesterone supplement versus placebo or no treatment  We are uncertain if vaginal progesterone increases LBR/OPR (risk ratio (RR) 1.10, 95% confidence interval (CI) 0.81 to 1.48; 7 RCTs; 1792 participants; low-certainty evidence) or decreases miscarriage per pregnancy compared to placebo or no treatment (RR 0.70, 95% CI 0.40 to 1.25; 5 RCTs; 261 participants). There were no data on LBR or miscarriage with oral stimulation. We are uncertain if progesterone increases LBR/OPR in women with gonadotropin stimulation (RR 1.24, 95% CI 0.80 to 1.92; 4 RCTs; 1054 participants; low-certainty evidence) and oral stimulation (clomiphene citrate or letrozole) (RR 0.97, 95% CI 0.58 to 1.64; 2 RCTs; 485 participants; low-certainty evidence). One study reported on OPR in women with gonadotropin plus oral stimulation; the evidence from this study was uncertain (RR 0.73, 95% CI 0.37 to 1.42; 1 RCT; 253 participants; low-certainty evidence). Given the low certainty of the evidence, it is unclear if progesterone reduces miscarriage per clinical pregnancy in any stimulation protocol (RR 0.68, 95% CI 0.24 to 1.91; 2 RCTs; 102 participants, with gonadotropin; RR 0.67, 95% CI 0.30 to 1.50; 2 RCTs; 123 participants, with gonadotropin plus oral stimulation; and RR 0.53, 95% CI 0.25 to 1.14; 2 RCTs; 119 participants, with oral stimulation). Low-certainty evidence suggests that progesterone in all types of ovarian stimulation may increase clinical pregnancy compared to placebo (RR 1.38, 95% CI 1.10 to 1.74; 7 RCTs; 1437 participants, with gonadotropin; RR 1.40, 95% CI 1.03 to 1.90; 4 RCTs; 733 participants, with gonadotropin plus oral stimulation (clomiphene citrate or letrozole); and RR 1.44, 95% CI 1.04 to 1.98; 6 RCTs; 1073 participants, with oral stimulation). 2. Progesterone supplementation regimen  We are uncertain if there is any difference between 300 mg and 600 mg of vaginal progesterone for OPR and multiple pregnancy (RR 1.58, 95% CI 0.81 to 3.09; 1 RCT; 200 participants; very low-certainty evidence; and RR 0.50, 95% CI 0.05 to 5.43; 1 RCT; 200 participants, very low-certainty evidence, respectively). No other outcomes were reported for this comparison. There were three different comparisons between progesterone regimens. For OPR, the evidence is very uncertain for intramuscular (IM) versus vaginal progesterone (RR 0.59, 95% CI 0.34 to 1.02; 1 RCT; 225 participants; very low-certainty evidence); we are uncertain if there is any difference between oral and vaginal progesterone (RR 1.25, 95% CI 0.70 to 2.22; 1 RCT; 150 participants; very low-certainty evidence) or between subcutaneous and vaginal progesterone (RR 1.05, 95% CI 0.54 to 2.05; 1 RCT; 246 participants; very low-certainty evidence). We are uncertain if IM or oral progesterone reduces miscarriage per clinical pregnancy compared to vaginal progesterone (RR 0.75, 95% CI 0.43 to 1.32; 1 RCT; 81 participants and RR 0.58, 95% CI 0.11 to 3.09; 1 RCT; 41 participants, respectively). Clinical pregnancy and multiple pregnancy were reported for all comparisons; the evidence for these outcomes was very uncertain. Only one RCT reported adverse effects. We are uncertain if IM route increases the risk of adverse effects when compared with the vaginal route (RR 9.25, 95% CI 2.21 to 38.78; 1 RCT; 225 participants; very low-certainty evidence). 3. GnRH agonist versus placebo or no treatment  No trials reported live birth. The evidence is very uncertain about the effect of GnRH agonist in ongoing pregnancy (RR 1.10, 95% CI 0.70 to 1.74; 1 RCT; 291 participants, very low-certainty evidence), miscarriage per clinical pregnancy (RR 0.73, 95% CI 0.26 to 2.10; 2 RCTs; 79 participants, very low-certainty evidence) and clinical pregnancy (RR 1.00, 95% CI 0.68 to 1.47; 2 RCTs; 340 participants; very low-certainty evidence), and multiple pregnancy (RR 0.28, 95% CI 0.11 to 0.70; 2 RCTs; 126 participants). 4. GnRH agonist versus vaginal progesterone  The evidence for the effect of GnRH agonist injection on clinical pregnancy is very uncertain (RR 1.00, 95% CI 0.51 to 1.95; 1 RCT; 242 participants). 5. HCG injection versus no treatment  The evidence for the effect of hCG injection on clinical pregnancy (RR 0.93, 95% CI 0.40 to 2.13; 1 RCT; 130 participants) and multiple pregnancy rates (RR 1.03, 95% CI 0.22 to 4.92; 1 RCT; 130 participants) is very uncertain. 6. Luteal support in natural cycle No study evaluated the effect of LPS in natural cycle. We could not perform sensitivity analyses, as there were no studies at low risk of selection bias and not at high risk in other domains.

AUTHORS' CONCLUSIONS

We are uncertain if vaginal progesterone supplementation during luteal phase is associated with a higher live birth/ongoing pregnancy rate. Vaginal progesterone may increase clinical pregnancy rate; however, its effect on miscarriage rate and multiple pregnancy rate is uncertain. We are uncertain if IM progesterone improves ongoing pregnancy rates or decreases miscarriage rate when compared to vaginal progesterone. Regarding the other reported comparisons, neither oral progesterone nor any other medication appears to be associated with an improvement in pregnancy outcomes (very low-certainty evidence).

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.

Does Luteal Phase Support Effect Pregnancy Rates in Intrauterine Insemination Cycles? A Prospective Randomised Controlled Study in a Tertiary Center

Intrauterine insemination (IUI) is a common treatment for couples with subfertility. Clomiphene citrate, gonadotropins, and letrozole are used for ovulation induction in IUI cycles. It has been well documented that luteal support with exogenous progesterone after in vitro fertilization is associated with higher pregnancy and live birth rates. Yet, luteal phase support in IUI cycles has become a debatable issue. The aim of this prospective controlled study was to assess the effect of luteal phase vaginal progesterone supplementation on β-hCG positivity and clinical pregnancy rates in women undergoing IUI. This prospective controlled randomised study was conducted at a tertiary infertility center. 87 patients with unexplained infertility or male subfertility who were treated with IUI using gonadotropins were enrolled. Patients in the study group (n = 44) received luteal phase vaginal progesterone supplementation. Patients in the control group (n = 43) did not receive any luteal phase support. There was no statistical difference between two groups in terms of β-hCG positivity and clinical pregnancy rates. Our findings do not show any beneficial effect of luteal phase support in IUI cycles stimulated with gonadotropins. Although luteal phase support in IUI cycles stimulated with gonadotropins is widely adopted, there is a lack of robust evidence.

The strength of evidence supporting luteal phase progestogen after assisted reproduction: A systematic review with reference to trial registration and pre-specified endpoints

OBJECTIVE

To measure the potential for outcome switching and selective reporting, in trials of luteal phase progestogen in assisted reproduction.

STUDY DESIGN

Trials identified through Medline and Embase in August 2017 using the MeSH term "assisted reproductive technology, luteal phase support" and associated text words. Randomised controlled trials (RCTs) comparing progestogen of any type, dose, and route of administration, with placebo or no treatment as luteal phase support in subfertile women undergoing in vitro fertilization (IVF) or intrauterine insemination (IUI). Eight trials after IVF and eleven after IUI, involving 1040 and 2764 participants respectively, were included.

RESULTS

None of the eight trials of progestogen therapy after IVF had been registered. Only 5/11 trials of progestogen after IUI had been registered, and only two of these prospectively. One of these had a registered primary outcome of "pregnancy sac plus heartbeat", but reported "pregnancy sac alone"; we judged this as an altered primary outcome. Three other trial had a registered primary outcome of "clinical pregnancy undefined" and reported "intra or extra-uterine pregnancy with a heartbeat"; we judged this alteration as minimal. That trial was negative. Overall, 26 different outcomes had been reported by the various trials. The three outcomes reported most often were pregnancy undefined (9/19), miscarriage (11/19) and clinical pregnancy (9/19). This suggests considerable potential for selective outcome reporting or outcome switching.

CONCLUSION

Apart from one negative trial, none of the evidence on luteal phase progestogen after assisted reproduction comes from prospectively registered trials: a slender reed indeed.

Does multifollicular development and number of intermediate follicles contribute to the effect of luteal phase support with vaginal progesterone gel in intrauterine insemination cycles?

Luteal phase deficiency as a result of multifollicular development which produces supraphysiological progesterone and estradiol levels and benefit of luteal phase support have been proven in assisted reproductive technique (ART) treatment. But, there were some controversial results in intrauterine insemination (IUI) cycles whether luteal phase support (LPS) with progesterone have an impact on pregnancy outcome. To assess the efficacy of vaginal progesterone gel in the gonadotropin-induced IUI cycles, this retrospective data analysis compared the luteal phase support and control group in terms of clinical pregnancy (CPR) and live birth rates (LBR). In subgroup analysis, multifollicular and monofollicular growth were analyzed separately. In total, after exclusion criteria, 380 IUI cycles were analyzed, cycles were grouped as LPS(+) and LPS(-) with 190 and 190 cycles, respectively. CPR and LBR were comparable between groups (11.6% vs. 10.5, p = .74 and 8.9% vs. 8.4%, p = .75 respectively). Although multifollicular growth demonstrated higher pregnancy outcomes than monofollicular growth, intermediate follicles (14-16 mm) had a positive impact on pregnancy outcome in monofollicular growth like multifollicular subgroup. We found no difference in CPR and LBR according to the luteal phase vaginal progesterone gel. Nevertheless, multifollicular cycles and also monofollicular growth cycles with two and more intermediate follicles may have benefit LPS in gonadotropin-induced IUI cycles.

[Impact of luteal phase support by human chorionic gonadotropin (hCG) in intrauterine inseminations]

OBJECTIVES

The objective of our study is to evaluate the impact of luteal phase support by hCG in intrauterine inseminations preceded by ovarian gonadotropin stimulation.

METHODS

A retrospective study was conducted at the CHU of Nice between March 1, 2016 and October 31, 2017. During this period, 300 intrauterine inseminations were included in data analysis. Ovarian stimulation was performed by gonadotropins and a GnRH antagonist was added, if needed. Following a modification of standard operative procedure in the department, patients who performed an intrauterine insemination from December 1, 2016 received luteal phase support with two injections of hCG 1500 IU, performed at three days of interval. Pregnancy and ovarian hyperstimulation syndrome were the primary and secondary study endpoints, respectively.

RESULTS

Out of 300 inseminations included in the analysis, 144 were performed with luteal phase support and 156 without support. No statistically significant difference in pregnancy rate was observed between these two groups (19.4% of pregnancy in the luteal phase support group and 15.38% in the group without luteal phase support, P=0.353). No ovarian hyperstimulation syndrome occurred over the course of the study.

CONCLUSION

Our study shows a slight improvement of pregnancy rate in the group subjected to luteal phase support by hCG after intrauterine insemination, but the benefit was not significant. A randomised prospective study based on a large cohort could help to assess the effect of luteal phase support during intrauterine inseminations.

Risk of pelvic inflammatory disease after intrauterine insemination: a systematic review

The aim of this study was to ascertain the incidence of pelvic inflammatory disease (PID) after intrauterine insemination (IUI). A systematic review was conducted using three different approaches: a search of IUI registries; a search of published meta-analyses; and a search of prospective randomized trials. Search terms were 'IUI', 'complications', 'infection' and 'PID'. Two IUI registers were identified that met the inclusion criteria, totalling 365,874 cycles, with 57 PID cases being reported. The post-IUI PID rate was 0.16/1000 (95% CI 0.2 to 0.3/1000). The frequency was higher in husband sperm cycles (0.21/1000) (28/135,839) than in donor sperm cycles (0.03/1000) (1/33,712) (P < 0.05; OR 6.95). Nineteen meta-analyses were retrieved, which included 156 trials, totalling 43,048 cycles, with no PID case being reported. Seventeen prospective clinical trials published between 2013 and 2014 were identified, totalling 4968 cycles; no PID case was reported. The reported rate of post-IUI clinical PID is low (0.16/1000), about 40% higher than reported in the general population of women during their reproductive life. No antibiotic prophylaxis should be recommended unless there is an associated risk factor.

Progesterone luteal support after ovulation induction and intrauterine insemination: an updated systematic review and meta-analysis

OBJECTIVE

To evaluate the effect of progesterone (P) for luteal phase support after ovulation induction (OI) and intrauterine insemination (IUI).

DESIGN

An updated systematic review and meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Patients undergoing OI-IUI for infertility.

INTERVENTION(S)

Exogenous P luteal support after OI-IUI.

MAIN OUTCOME MEASURE(S)

Live birth.

RESULT(S)

Eleven trials were identified that met inclusion criteria and constituted 2,842 patients undergoing 4,065 cycles, more than doubling the sample size from the previous meta-analysis. In patients receiving gonadotropins for OI, clinical pregnancy (relative risk [RR] 1.56, 95% confidence interval [CI] 1.21-2.02) and live birth (RR 1.77, 95% CI 1.30-2.42) were more likely in P supplemented patients. These findings persisted in analysis of live birth per IUI cycle (RR 1.59, 95% CI 1.24-2.04). There were no data on live birth in clomiphene citrate or clomiphene plus gonadotropin cycles. There was no benefit on clinical pregnancy with P support for patients who underwent OI with clomiphene (RR 0.85, 95% CI 0.52-1.41) or clomiphene plus gonadotropins (RR 1.26, 95% CI 0.90-1.76).

CONCLUSION(S)

Progesterone luteal phase support is beneficial to patients undergoing ovulation induction with gonadotropins in IUI cycles. The number needed to treat is 11 patients to have one additional live birth. Progesterone support did not benefit patients undergoing ovulation induction with clomiphene citrate or clomiphene plus gonadotropins.

Impact of luteal phase support with vaginal progesterone on the clinical pregnancy rate in intrauterine insemination cycles stimulated with gonadotropins: a randomized multicenter study

OBJECTIVE

To evaluate the effect of luteal phase support (LPS) in intrauterine insemination (IUI) cycles stimulated with gonadotropins.

DESIGN

Randomized multicenter trial.

SETTING

Academic tertiary care centers and affiliated secondary care centers.

PATIENT(S)

Three hundred and ninety-three normo-ovulatory patients, <43 years, with body mass index ≤30 kg/m², in their first IUI cycle, with at least one patent tube, a normal uterine cavity, and a male partner with total motile sperm count ≥5 million after capacitation.

INTERVENTION(S)

Gonadotropin stimulation, IUI, randomization to LPS using vaginal progesterone gel (n = 202) or no LPS (n = 191).

MAIN OUTCOME MEASURE(S)

Clinical pregnancy rate, live-birth rate, miscarriage rate, and duration of the luteal phase.

RESULT(S)

The primary outcome, the clinical pregnancy rate, was not statistically different between the treatment group (16.8%) and the control group (11%) (relative risk [RR] 1.54; 95% confidence interval [CI], 0.89-2.67). Similarly, the secondary outcome, the live-birth rate, was 14.9% in the treatment group and 9.4% in the control group (RR 1.60; 95% CI, 0.89-2.87). The mean duration of the luteal phase was about 2 days longer in the treatment group (16.6 ± 2.2 days) compared with the control group (14.6 ± 2.5 days) (mean difference 2.07; 95% CI, 1.58-2.56).

CONCLUSION(S)

Although a trend toward a higher clinical pregnancy rate as well as live-birth rate was observed in the treatment group, the difference with the control group was not statistically significant.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01826747.

Luteal phase support after mild ovulation induction with intrauterine insemination: an on-going debate

OBJECTIVE

To evaluate the effect of luteal phase support (LPS) using progesterone vaginal gel on pregnancy rate (PR) and live birth rate (LBR) during cycles in which controlled ovarian stimulation (COH) was performed using gonadotropins with intrauterine insemination (IUI) cycles in patients with unexplained infertility and polycystic ovarian syndrome.

MATERIALS AND METHODS

From 2010 to 2015, all IUI cycles in which COH was performed using gonadotropins were evaluated retrospectively. LPS was not used until July 2013, after which vaginal progesterone gel was applied in the luteal phase of IUI cycles. Both groups of patients were evaluated in terms of the effect of LPS on PR and LBR.

RESULTS

In total, 1578 IUI cycles were evaluated, of which 481 were LPS (+) and 1097 LPS (-). PR and LBR per cycle were 10.6% and 7.4%, respectively, in the LPS (+) group, and 11.6% and 7.7%, respectively, in the LPS (-) group (p = 0.31 and p = 0.25). PR and LBR per patient were 17% and 12%, respectively, in the LPS (+) group, and 17.4% and 12.3%, respectively, in the LPS (-) group (p = 0.48 and p = 0.82).

CONCLUSIONS

We found no difference in PR and LBR per cycle and per patient according to the use of LPS in IUI cycles in which COH was performed using gonadotropins. Thus, routine use of LPS in gonadotropin-stimulated cycles requires further research involving larger numbers of patients.

Luteal phase support in intrauterine insemination cycles: a prospective randomized study of 300 mg versus 600 mg intravaginal progesterone tablet

Vaginal progesterone (P) has been suggested to be used for luteal phase support (LPS) in controlled ovarian stimulation (COH)-intrauterine insemination (IUI) cycles, however, no concensus exists about the best P dose. Therefore, considering the fecundability rate as the primary end point, our main objective was to find the optimal dose of P in COH-IUI cycles, comparing the two groups of women, each of which comprised of 100 women either on 300 mg or 600 mg of intravaginal P tablets, in a prospective randomized study design. The mean age of the women, duration of infertility, basal and day of hCG injection hormone levels in the female and sperm parameters were similar in the two study groups. Also, duration and dose of gonadotropin given, number of follicles, endometrial thickness, the total, ongoing and multiple pregnancy rates were comparable in both groups. We, therefore, claim that 300 mg of intravaginal micronized P should be the maximum dose of LPS in IUI cycles.

Effect of luteal phase support after ovulation induction and intrauterine insemination

OBJECTIVE

This study aimed to evaluate the effect of luteal phase support on clinical pregnancy and live birth rates after ovulation induction and intrauterine insemination (IUI).

METHODS

579 cycles from 2010 to 2013 were retrospectively evaluated. Ovarian stimulation was performed with gonadotropins, and rHCG was used for ovulation triggering. All patients received IUI. 451 cycles were supported by receiving vaginal micronized progesterone capsules (142 cycles) or vaginal progesterone gel (309 cycles) whereas 128 cycles were not supported.

RESULTS

Clinical pregnancy (20.6 versus 9.4%; p = 0.004) and live birth rates (14 versus 7%; p = 0.036) were higher for supported group than for unsupported group. Progesterone gel and micronized progesterone subgroups achieved similar clinical pregnancy and live birth rates (21.4 versus 19%, p = 0.567 and 14.2 versus 13.4%, p = 0.807; respectively).

CONCLUSIONS

Luteal phase support improved the success of IUI cycles affecting both clinical pregnancy and live birth rates when gonadotropins were used for ovulation induction. The use of vaginal progesterone gel or micronized progesterone significantly improves clinical pregnancy rates. The live birth rates were higher in the progesterone gel group, but were similar in the micronized progesterone group compared to the unsupported group.