Extension of the clomiphene citrate stair-step protocol to gonadotropin treatment in women with clomiphene resistant polycystic ovarian syndrome

The stair-step approach in treatment of anovulatory PCOS patients

Clomiphene citrate (CC) is a widely accepted first-line treatment for anovulatory patients with polycystic ovarian syndrome (PCOS). The current practice is to prescribe CC with gradual dose increments until ovulation is achieved. Typically, progesterone withdrawal bleeding is induced between each dose increment and before the commencement of gonadotropin therapy in CC-resistant patients. It has been recently suggested that dose increments of CC can be administered once failure to induce ovulation at a certain dose has been documented, without induction of progesterone withdrawal bleeding, and this approach has been nicknamed the clomiphene-citrate stair-step (CC-SS) protocol. The same principle has been found feasible before introducing gonadotropin therapy in CC-resistant PCOS patients. Our objective was to review the world literature on the CC-SS protocol and to summarize our own experience with extending the CC-SS approach to initiation of gonadotropin therapy. Studies on CC-SS protocol (n = 4) have found that this approach leads to a significant reduction of the time to ovulation and to an increased ovulation rate. In our own retrospective case series, 18 CC-resistant PCOS patients initiated gonadotropin stimulation without induction of progesterone withdrawal bleeding, using the chronic low-dose regimen. The time to ovulation in the study group was 54.2 ± 6.2 days, while the estimated time to ovulation calculated according to the traditional approach was approximately 110 days. The clinical pregnancy rate was 44% (8/18), and all pregnancies were singletons. One patient miscarried; hence, the live birth rate was 38.9% (7/18). In summary, the CC-SS approach and its extension to the initiation of gonadotropin therapy results in considerable reduction of the time to ovulation, and favorable ovulation rates and reproductive outcome. Large-scale confirmation of these findings by properly designed randomized controlled trials may lead to a change of practice in the treatment of anovulatory infertility in PCOS patients, allowing simplification of treatment and a shorter time to ovulation and pregnancy.

Ovulation rates in a stair-step protocol with Letrozole vs clomiphene citrate in patients with polycystic ovarian syndrome

PURPOSE

To compare ovulation rates between Letrozole and Clomiphene Citrate (CC) using a stair-step protocol to achieve ovulation induction in women with Polycystic Ovarian Syndrome (PCOS).

METHODS

This is a retrospective cohort of predominantly Hispanic PCOS women of reproductive age who completed ovulation induction (OI) comparing women who underwent Letrozole stair-step protocol to those who underwent OI with CC stair-step. All women had a diagnosis of PCOS based on the 2003 Rotterdam criteria. For both protocols, sequentially higher doses of Letrozole or CC were given 7 days after the last dose if no dominant follicles were seen on ultrasonography. The primary outcome was ovulation rate (determined by presence of a dominant follicle) between the two treatment groups. Secondary outcomes included time to ovulation, clinical pregnancy rates and side effects.

RESULTS

49 PCOS patients completed a Letrozole stair-step cycle and 43 completed a CC stair-step cycle for OI. Overall, demographics were comparable between both groups. Ovulation rates with the Letrozole stair-step protocol were equivalent to CC stair-step protocol (96% vs 88%, p = 0.17). Although the mean time (days) to ovulation was shorter in the Letrozole group (19.5 vs 23.1, p = 0.027), the pregnancy rates were similar for both groups.

CONCLUSIONS

This is the first study to date that has compared the efficacy of the stair-step protocol in PCOS patients using Letrozole and CC. Both Letrozole and CC can be prescribed in a stair-step fashion. Letrozole stair-step was as efficacious as CC stair-step; patients achieved comparable rates of ovulation and clinical pregnancy. Time to ovulation was shorter in the Letrozole protocol.