Extending letrozole treatment duration is effective in inducing ovulation in women with polycystic ovary syndrome and letrozole resistance

Bilateral tubal ectopic pregnancy following induction ovulation can be missed in emergent ultrasonography: Case report

INTRODUCTION

Bilateral tubal ectopic pregnancy (BTP) is a rare and potentially life-threatening condition that is, often challenging to diagnose preoperatively.

PRESENTATION OF CASE

We present a case of BTP in a 25-year-old primigravid woman with a history of infertility due to polycystic ovarian syndrome. She was receiving letrozole when she presented with severe abdominal pain and vaginal bleeding. Initial evaluation revealed a ruptured ectopic pregnancy in the right fallopian tube, prompting an emergency laparotomy. During surgery, a second intact ectopic mass was discovered in the left fallopian tube, highlighting the diagnostic complexity of BTP. Management involved a salpingectomy on the right side and salpingostomy on the left to preserve fertility.

DISCUSSION

This case underscores the importance of considering BTP in the differential diagnosis of ectopic pregnancies and the necessity for thorough preoperative imaging studies, namely ultrasonography and surgical exploration, to prevent missed diagnoses.

CONCLUSION

BTP is a rare and challenging clinical entity that requires a comprehensive approach to diagnosis and management. Early recognition, prompt intervention, and close surveillance are essential to mitigate the risk of maternal morbidity and mortality associated with this condition.

Extended versus conventional letrozole regimen in patients with polycystic ovary syndrome undergoing their first ovulation induction cycle: a prospective randomized controlled trial

STUDY QUESTION

Can an extended letrozole (LE) regimen result in a higher ovulatory rate than a conventional regimen in patients with polycystic ovary syndrome (PCOS) undergoing their first ovulation induction cycle?

SUMMARY ANSWER

There was no statistical difference in ovulation rate between patients with PCOS using the extended LE regimen and those using the conventional LE regimen.

WHAT IS KNOWN ALREADY

LE has become the first-line agent for ovulation induction. However, there is still a proportion of non-responsive cycles in patients with PCOS undergoing ovulation induction therapy with LE alone, and the extended LE regimen has been demonstrated to be a feasible method for inducing ovulation in these non-responders. Nevertheless, whether the extended regimen could be applied to all patients with PCOS as a first choice for the induction of ovulation remains to be explored.

STUDY DESIGN SIZE DURATION

This was a prospective randomized controlled trial that included 148 female patients with PCOS who underwent their first ovulation induction cycle with LE from January 2021 to October 2022.

PARTICIPANTS/MATERIALS SETTING METHODS

Participants were randomly assigned to receive an extended (5 mg LE daily for 7 days) or conventional regimen (5 mg LE daily for 5 days) for one treatment cycle. The ovulation rate was the primary outcome. Secondary outcomes included the clinical pregnancy rate, the number of preovulatory follicles, and the rate of multiple pregnancies.

MAIN RESULTS AND THE ROLE OF CHANCE

The ovulation rate among patients receiving an extended LE regimen was slightly higher than the rate with a conventional LE regimen, but the difference did not reach statistical significance in either the intention-to-treat analysis (90.54% [67/74] vs 79.73% [59/74], P = 0.065; relative risk [95% CI]: 0.881 [0.768-1.009]) or the per-protocol analysis (90.54% [67/74] vs 84.29% [59/70], P = 0.257; relative risk [95% CI]: 0.931 [0.821-1.055]). The number of preovulatory follicles was nearly identical in the two groups (1.39 ± 0.62 vs 1.37 ± 0.59, P = 0.956), and no cases of ovarian hyperstimulation syndrome were observed. With regards to the endometrial parameters, the mean endometrium thickness was slightly thicker with the conventional LE regimen compared to that with the extended LE regimen, though with no statistical difference (9.27 ± 1.72 mm vs 9.57 ± 2.28 mm, P = 0.792). In the per-protocol analysis, the rates of clinical pregnancy (20.27% [15/74] vs 14.29% [10/70], P = 0.343; relative risk [95% CI]: 0.705 [0.34-1.463]) and live birth (13.51% [10/74] vs 11.43% [8/70], P = 0.705; relative risk [95% CI]: 0.846 [0.354-2.019]) did not differ significantly between treatment groups. Moreover, all conceptions were singletons without neonatal defects.

LIMITATIONS REASONS FOR CAUTION

The major concerns regarding this study are its single-center and open-label nature. Additionally, the limited number of lean patients with PCOS with a mean body mass index of 23-25 kg/m2 enrolled in our trial also restricted the generalizability of our findings.

WIDER IMPLICATION OF THE FINDINGS

A change from the standard strategy of ovulation induction in patients with PCOS is not advisable, because a statistically superior effect of the extended LE regimen over a conventional regimen was not detected. The extended LE regimen could be applied with caution in a specific population who failed to respond to a conventional regimen rather than all the patients with PCOS during ovulation induction. Additional prospective trials with larger sample sizes and different PCOS subgroups are needed to assess the ovulatory effects of various LE treatment durations.

STUDY FUNDING/COMPETING INTERESTS

This study was funded by the Shanghai First Maternity and Infant Hospital, affiliated with Tongji University School of Medicine (grant numbers: 2023B03 to Y.F., 2023B18 to X.Z., and 2020RC02 to Y.F.). The authors report no conflicts of interest.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry (ChiCTR2100042082).

TRIAL REGISTRATION DATE

13 January 2021.

DATE OF FIRST PATIENT’S ENROLMENT

21 January 2021.

A comparison of letrozole regimens for ovulation induction in women with polycystic ovary syndrome

Objective

To determine the optimal letrozole regimen for ovulation induction (OI) in women with polycystic ovary syndrome (PCOS).

Design

Retrospective cohort study.

Setting

Single academic fertility clinic from 2015-2022.

Patients

A total of 189 OI cycles in 52 patients with PCOS.

Interventions

Patients were prescribed 1 of 4 letrozole regimens (group 1: 2.5 mg for 5 days, group 2: 2.5 mg for 10 days, group 3: 5 mg for 5 days, and group 4: 5 mg for 10 days).

Main outcome measures

The primary outcome was ovulation, and secondary outcomes included multifollicular development, and clinical pregnancy rate, which were analyzed with binary logistic regression. Kaplan-Meier cumulative response curves and a Cox proportional hazard regression model were used for time-dependent analyses.

Results

Mean age was 30.9 years (standard deviation [SD], 3.6) and body mass index was 32.1 kg/m2 (SD, 4.0). Group 2 (odds ratio [OR], 9.12; 95% confidence interval [CI], 1.92-43.25), group 3 (OR, 3.40; 95% CI, 1.57-7.37), and group 4 (OR, 5.94; 95% CI, 2.48-14.23) had improved ovulation rates after the starting regimen as compared with group 1. Cumulative ovulation rates exceeded 84% in all groups, yet those who received 5 mg and/or 10 days achieved ovulation significantly sooner. Multifollicular development was not increased in groups 2-4 as compared with group 1. Groups 2-4 also demonstrated improved time to pregnancy.

Conclusions

Ovulation rates are improved when starting with letrozole at 5 mg and/or a 10-day extended course as compared with the frequently-used 2.5 mg for 5 days. This may shorten time to ovulation and pregnancy.

Ovulation induction with letrozole and dexamethasone in infertile patients with letrozole-resistant polycystic ovary syndrome

PURPOSE

To assess efficacy of adjuvant dexamethasone during letrozole cycles for ovulation induction (OI) in women with letrozole-resistant polycystic ovary syndrome (PCOS).

METHODS

We retrospectively evaluated 42 cycles of OI from 28 infertile women with letrozole-resistant PCOS between September 2019 and November 2022. Letrozole was initiated on cycle day 3 for 5 days and increased via a stair-step approach to 7.5 mg as indicated. Patients were deemed letrozole-resistant if no dominant follicle was identified on transvaginal ultrasound following this dose. Resistant patients then received 5 additional days of letrozole 7.5 mg with low-dose dexamethasone 0.5 mg for 7 days and had a repeat ultrasound. The primary outcome was ovulation rate determined by the presence of a dominant follicle on ultrasound. Secondary outcomes included endometrial thickness, number of measurable follicles, and pregnancy outcomes among responders.

RESULTS

Twenty-two of 28 (79%) letrozole-resistant PCOS patients had evidence of ovulation after the addition of dexamethasone in 35 out of 42 (83%) cycles. Clinical pregnancy occurred in 20% of ovulatory cycles with a cumulative rate of 32%. All clinical pregnancies resulted in a live birth. Patients who responded to adjuvant dexamethasone were more likely to have a shorter duration of infertility; however, there were no differences in other demographics, serum androgens including DHEA-S, or pretreatment glycemic status.

CONCLUSION

Adding dexamethasone to letrozole increased ovulation rates in letrozole-resistant PCOS patients undergoing OI with similar pregnancy outcomes to prior studies. The addition of dexamethasone is an effective, inexpensive, and safe option for PCOS patients otherwise at risk for cycle cancelation.