Flexible ovarian stimulation in a poor responder: a case report and literature review

GnRH agonist trigger in poor prognosis patients undergoing a multicycle approach through DuoStim or consecutive stimulations: a SWOT analysis

PURPOSE OF REVIEW

Identify the most recent and significant evidence regarding the ovulation trigger within the framework of a multicycle approach through DuoStim, providing valuable insights for improving treatment strategies in patients with a poor prognosis.

RECENT FINDINGS

The trigger method plays a pivotal role in optimizing in-vitro fertilization (IVF) stimulation, influencing oocyte retrieval and maturation rates, as well as follicle recruitment in consecutive ovarian stimulations such as double stimulation. Decision-making involves multiple factors and, while guidelines exist for conventional stimulation, specific recommendations for the multicycle approach are not well established.

SUMMARY

The different methods for inducing oocyte maturation underscore the need for personalization of IVF protocols. The GnRH agonist trigger induces rapid luteolysis and establishes favorable hormonal conditions that do not adversely affect the recruitment of consecutive follicular waves in the context of DuoStim. It serves as a valid alternative to hCG in freeze-all cycles. This strategy might enhance the safety and flexibility of ovarian stimulations with no impact on oocyte competence and IVF efficacy.

Luteal Phase Stimulation in the Same Cycle Is an Effective Strategy to Rescue POSEIDON Poor Responders with No Embryos after the First Follicular Stimulation

Background

Poor responders may benefit from recruiting a 'second wave' of antral follicles within the same cycle. This concept forms the basis of double stimulation which has been named as 'DuoStim'. This protocol involves ovarian stimulation in both follicular and luteal phases with egg retrieval in each phase, respectively, to increase the number of oocytes and embryos in one menstrual cycle. This can be considered a potentially valuable option for women with poor ovarian reserve/response to maximise the number of oocytes retrieved in a single ovarian cycle in the shortest possible time.

Aims

The aim of this study was to evaluate the efficacy of the DuoStim protocol in women classified as POSEIDON poor responders undergoing in vitro fertilization by comparing the embryological outcomes between the follicular and luteal phase stimulations in the same menstrual cycle.

Settings and Design

This was a retrospective cohort study of 131 patients who enrolled to undergo DuoStim cycles from January 2021 to Sept. 2022, at a IVF center in a tertiary care hospital.

Materials and Methods

The follicular phase stimulation used a standard antagonist protocol for the first oocyte retrieval. Thereafter, the luteal phase stimulation was started 3 days after the first retrieval, with the same dose of gonadotropin along with a daily 10 mg medroxyprogesterone acetate tablet, followed by a second oocyte retrieval. Blastocysts produced in both the phases were subsequently vitrified.

Statistical Analysis Used

The paired t-test was used for comparing means and 95% confidence intervals (CIs) for different parameters. McNemar's test was used to compare paired proportions. The analysis was conducted using R statistical environment 4.2.

Results

The mean number of oocytes retrieved and the mean number of utilizable blastocysts frozen per stimulation cycle were found to be significantly higher in the luteal phase as compared to the follicular phase (5.71 ± 3.95 vs. 4.87 ± 2.79, P = 0.02, and 1.43 ± 1.22 vs. 0.95 ± 1, P = 0.001, respectively). However, the mean fertilization rate and the mean blastocyst utilization rate were found to be similar between both the phases. The length of stimulation was found to be approximately 3 days longer in the luteal phase (12.63 ± 2.43 vs. 9.75 ± 1.85, P = 0.001). Overall, the odds of obtaining a usable blastocyst in the luteal phase was found to be significantly higher than in the paired follicular phase (73.9% vs. 57.7%, P = 0.012, odds ratio: 2.286 [95% CI: 1.186-4.636]). Also importantly, the luteal phase stimulation was able to rescue 68% (32/47) of patients where no blastocysts were formed in the follicular phase.

Conclusion

Our data demonstrate that in women with poor reserve, the addition of luteal stimulation could increase the chances of achieving a pregnancy by significantly increasing the number of eggs and transferable embryos per menstrual cycle compared to follicular stimulation alone. Furthermore, luteal phase stimulation in the same cycle proved to be an effective strategy to rescue POSEIDON poor responders with no embryos after the first stimulation.

Double stimulation for the management of poor-prognosis patients: where are we going?

PURPOSE OF REVIEW

The technical improvements in IVF allowed the implementation of nonconventional ovarian stimulation protocols for some specific patients. Where time is crucial, such as with oncologic patients, poor-prognosis patients, patients with low ovarian reserve, and those with advanced maternal age, access to IVF treatment is even more critical. Some of these protocols might start in the late follicular phase, luteal phase, or involve both stimulations within the same ovarian cycle.

RECENT FINDINGS

Until now, published evidence showed that oocytes retrieved from unconventional protocol seem to be developmentally, genetically, and reproductively competent. Second stimulation in the same ovarian cycle after the conventional approach may represent a sound alternative to oocyte accumulation. This can be proposed in progress after careful counselling focused on the patients' chances of finding at least one euploid embryo on account of their age and of the number of blastocysts obtained after the conventional approach.

SUMMARY

The adoption of these new strategies, known as double stimulation protocol, can be conceived as a real full-personalization of ovarian stimulation. Multicentre prospective RCTs are urgently needed to evaluate the efficacy, efficiency, and costs of double stimulation versus two consecutive conventional approaches with standard or mild stimulation and in a different IVF setting.

Development of a predictive model for luteal phase oocyte retrieval in poor responders undergoing natural cycle IVF

The aim of this study is the development of a prediction model indicating successful application of Oocyte Retrieval performed during the Luteal Phase (LuPOR) in poor responders, as defined by the retrieval of at least one MII oocyte. Recruitment included 1688 poor responders diagnosed as per Bologna Criteria, undergoing natural cycle ICSI between 2012 and 2020. Oocyte collections were performed during the follicular phase and during the luteal phase similarly. Antral Follicle Count (AFC), Estradiol (E₂) levels evaluated on both trigger days prior to Follicular Phase Oocyte Retrieval (FoPOR) and LuPOR, and the number of small follicles 8–12 mm that were not aspirated during FoPOR were identified as predictive factors indicative of an efficient LuPOR practice with an Area Under the Curve (AUC) of 0.86, 0.86, 0.89 as well as 0.82 respectively. The combination of the above-mentioned characteristics into a prediction model provided an AUC of 0.88, specificity and a sensitivity of 0.73 and 0.94 respectively and an accuracy of 0.89. The model provided a positive predictive value (PPV) of 93.5% and a negative predictive value (NPV) of 46.8%. The clinical conclusion of the present study aims to be of added value to the clinician, by providing a prediction model defining the POR population benefiting from LuPOR. The high PPV of this model may renders this tool helpful for the practitioner that considers LuPOR.

Dydrogesterone primed luteal phase stimulation may be better than follicular phase stimulation in patients with diminished ovarian reserve

OBJECTIVE

In this study, we aimed to compare the efficacy of luteal phase stimulation (LPS) and follicular phase stimulation (FPS) in two separate menstrual cycles (2-5 months intervals) of the same patient, utilizing LPS with dydrogesteron only.

METHODS

This retrospective case control study was conducted with patients with diminished ovarian reserve (DOR) (Group 1) and infertile patients with Anti-Müllerian hormone >1.2 ng/mL (Group 2) undergoing two ovarian stimulations (FPS and LPS with dydrogesteron only) and two oocyte retrievals in two separate menstrual cycles (2-5 months intervals) in the Division of Reproductive Endocrinology and Infertility of Baskent University, Ankara, between April 2019 and December 2019.

RESULTS

In group 1, the number of frozen embryos was significantly higher in LPS when compared to FPS; 1.71 vs. 0.54, (p < .001), respectively. In group 2, the number of frozen embryos was higher in LPS when compared to FPS (0.8 vs. 0.4) however the difference did not reach a statistical significance (p: 0.157).

CONCLUSION

LPS may be beneficial especially in the patients with diminished ovarian reserve with follicular asynchronization in the menstrual onset. In addition, it should be kept in mind that dydrogesterone only may be used instead of gonadotropin-releasing hormone antagonist to prevent possible luteinizing hormone rise in LPS.

Follicular waves in ontogenesis and female fertility

Antral follicle growth and recruitment are the basis of female reproduction. Follicular wave theory explains the recruitment, growth, and selection of antral follicles. This article is devoted to the follicular wave pattern in female reproduction throughout life. We highlight progress in understanding the rhythmic follicle changes based on clinical studies and studies on animal models. We review the follicular wave pattern before puberty, during pregnancy, and in perimenopause. Several mathematical models are known which quite accurately describe follicular wave dynamics. The follicular waves theory allows the implementation of the new approaches to ovarian stimulation. Stimulation in the luteal phase and double stimulation are used more widely nowadays for fertility preservation in cancer patients and for increasing the chances of IVF programs success in poor responder patients.

Double or dual stimulation in poor ovarian responders: where do we stand?

Recent advances in our recognition of two to three follicular waves of development in a single menstrual cycle has challenged the dogmatic approach of ovarian stimulation for in vitro fertilization starting in the early follicular phase. First shown in veterinary medicine and thereafter in women, luteal phase stimulation–derived oocytes are at least as competent as those retrieved following follicular phase stimulation. Poor ovarian responders still remain a challenge for many decades simply because they do not respond to ovarian stimulation. Performing follicular phase stimulation and luteal phase stimulation in the same menstrual cycle, named as double stimulation/dual stimulation, clearly increases the number of oocytes, which is a robust surrogate marker of live birth rate in in vitro fertilization across all female ages. Of interest, apart from one study, the bulk of evidence reports significantly higher number of oocytes following luteal phase stimulation when compared with follicular phase stimulation; hence, performing double stimulation/dual stimulation doubles the number of oocytes leading to a marked decrease in patient drop-out rate which is one of the major factors limiting cumulative live birth rates in such poor prognosis patients. The limited data with double stimulation/dual stimulation-derived embryos is reassuring for obstetric and neonatal outcome. The mandatory requirement of freeze-all and lack of cost-effectiveness data are limitations of this novel approach. Double stimulation/dual stimulation is an effective strategy when the need to obtain oocytes is urgent, including patients with malignant diseases undergoing oocyte cryopreservation and patients of advanced maternal age or with reduced ovarian reserve.

Ongoing pregnancy and healthy live births following very short ovarian stimulation of incidentally observed big antral follicles in oligoamenorrheic patients with extremely decreased ovarian reserve

In the present case series our aim is to present seven patients with extremely decreased ovarian reserve and oligomenorrhea, conceived with in vitro fertilization following a very short ovarian stimulation of incidentally detected big antral follicles. The study included women pursuing in vitro fertilization due to premature ovarian failure risk. When an incidental growing antral follicle was detected under ultrasound, immediate ovarian stimulation was initiated if the blood estradiol, luteinizing hormone and progesterone levels were correlated. Serum anti-Mullerian hormone measurements of all patients were consistent with extremely diminished ovarian reserve (ranged between 0.01 and 0.09ng/ml) and FSH levels varied between 13-104IU/l. The mean stimulation length ranged between 2-4 days. A total of 8 oocytes were retrieved; 6 MII, 1 GV and 1 degenerated. All 6 MII oocytes were fertilized with intracytoplasmic sperm injection. Two patients conceived after fresh embryo transfer, whereas the one conceived following frozen thawed embryo transfer. The ongoing pregnancy rate was 50% per transfer, and two of them resulted in a healthy live birth. In conclusion, close monitoring of oligoamenorrheic infertile patients who are at high risk of imminent ovarian failure using ultrasound and blood hormone levels is very important. Albeit low, the possibility of having a healthy pregnancy following “a very short ovarian stimulation” in such a specific patient group is emphasized.

Ovarian follicular waves during the menstrual cycle: physiologic insights into novel approaches for ovarian stimulation

Elucidation of multiple waves of antral ovarian follicular development during the menstrual cycle has challenged traditional concepts of female reproductive physiology and foundations of assisted reproductive therapies. Approximately two-thirds of women develop two follicle waves throughout an interovulatory interval and the remainder exhibit three waves of follicle development. Major and minor waves of follicle development have been observed. Major waves are those in which a dominant follicle develops; dominant follicles either regress or ovulate. In minor waves, physiologic selection of a dominant follicle is not manifest. Knowledge of waves of antral follicular development has led to the global adoption of novel ovarian stimulation strategies in which stimulation can be initiated at various times throughout the cycle. Random-start and luteal-phase ovarian stimulation regimens have had important clinical applications for women requiring urgent oocyte or embryo cryopreservation for fertility preservation prior to chemotherapy. Ovarian stimulation twice in the same cycle, referred to as double stimulation, may be used to optimize clinical outcomes in women with a poor ovarian response to stimulation as well as in those requiring fertility preservation before chemotherapy.

DuoStim - a reproducible strategy to obtain more oocytes and competent embryos in a short time-frame aimed at fertility preservation and IVF purposes. A systematic review

Recent evidence suggests that follicular development occurs in a wave-like model during the ovarian cycle, where up to three cohorts of follicles are recruited to complete folliculogenesis. This understanding overtakes the previous dogma stating that follicles grow only during the follicular phase of the menstrual cycle. Therefore, in in vitro fertilization (IVF), novel protocols regarding ovarian stimulation have been theorized based on the use of gonadotrophins to prompt the growth of antral follicles at any stage of the menstrual cycle. These unconventional protocols for ovarian stimulation aim at a more efficient management of poor-prognosis patients, otherwise exposed to conflicting outcomes after conventional approaches. DuoStim appears among these unconventional stimulation protocols as one of the most promising. It combines two consecutive stimulations in the follicular and luteal phases of the same ovarian cycle, aimed at increasing the number of oocytes retrieved and embryos produced in the short time-frame. This protocol has been suggested for the treatment of all conditions requiring a maximal and urgent exploitation of the ovarian reserve, such as oncological patients and poor responders at an advanced maternal age. At present, data from independent studies have outlined the consistency and reproducibility of this approach, which might also reduce the drop-out between consecutive failed IVF cycles in poor-prognosis patients. However, the protocol must be standardized, and more robust studies and cost-benefit analyses are needed to highlight the true clinical pros and cons deriving from DuoStim implementation in IVF.

Assessing the practice of LuPOR for poor responders: a prospective study evaluating follicular fluid cfDNA levels during natural IVF cycles

PURPOSE

The aim of this study is to provide data on the practice of Luteal Phase Oocyte Retrieval (LuPOR). The authors assess cell-free DNA levels in follicular fluid (ff cfDNA) from poor responders undergoing natural cycles, and comparing it to respective data originating from follicular phase oocyte retrievals.

METHODS

Forty-seven women were eligible for this prospective study. Participants were classified as poor responders based on Bologna criteria while being detected with a second follicular wave. Follicular fluid was collected and prepared for cfDNA extraction. Levels of cfDNA were quantified via Q-PCR employing the ALU115 and ALU247 primers. These primers are associated with apoptotic and necrotic events. Levels of ff cfDNA resulting from follicular phase oocyte retrieval (FoPOR) and LuPOR-performed in a single menstrual cycle were associated with the number and maturation status of yielded oocytes and the number and fertilization status of resulting zygotes. Survival rate following thawing of cryopreserved zygotes, along with the resulting number of cleavage stage and blastocyst stage embryos are provided.

RESULTS

Mean levels of ALU115 were significantly lower during FoPOR when compared to LuPOR (0.79 ± 0.72 vs 1.46 ± 1.59 ng/μl, p = 0.02). Regarding the FoPOR group, a significant positive correlation of serum estradiol and ALU115 concentration (p = 0.04) was revealed. A significant negative correlation between serum estradiol and cfDNA integrity was observed both during FoPOR (p = 0.03) and LuPOR (p = 0.03). A significant lower number of retrieved (1.09 ± 0.28 vs 1.29 ± 0.58, p = 0.02) and MII oocytes (0.77 ± 0.55 vs 1.08 ± 0.61, p = 0.02) was observed when comparing the FoPOR to LuPOR groups respectively. The integrity of cfDNA was observed to be higher in FoPOR originating embryos that arrested either prior to cleavage (0.28 ± 0.13 vs 0.17 ± 0.10, p = 0.006) or prior to blastocyst formation (0.28 ± 0.12 vs 0.13 ± 0.06, p = 0.04). In the case of LuPOR originating embryos, cfDNA integrity was observed to be higher in embryos that arrested only prior to the blastocyst stage (0.27 ± 0.20 vs 0.11 ± 0.07, p = 0.008). Similarly, cfDNA integrity was observed to be lower in top quality blastocysts originating from FoPOR (0.07 ± 0.04 vs 0.17 ± 0.05, p = 0.03) and in top quality cleavage stage embryos (0.09 ± 0.06 vs 0.31 ± 0.22, p = 0.01) and blastocysts (0.06 ± 0.02 vs 0.14 ± 0.06, p = 0.02) originating from LuPOR.

CONCLUSIONS

Our results indicate that ff originating from LuPOR presents with higher levels of cfDNA. The higher cfDNA levels are attributed to mainly apoptotic events, as the ALU247 levels and DNA integrity did not differ statistically significantly between FoPOR and LuPOR. The absolute mean level of ALU247 corresponding to necrotic events was higher in LuPOR. Regarding embryological data, cfDNA integrity was correlated with both number and quality of cleavage stage embryos in both FoPOR and LuPOR, along with blastocyst stage embryos in LuPOR. Necrotic events were associated with poorer blastocyst formation rate and blastocyst quality in LuPOR. As the comparison between FoPOR and LuPOR results to similar IVF laboratory data, the practice of LuPOR may stand as a promising approach for poor responders, while it merits further investigation.

Evaluation of the Second Follicular Wave Phenomenon in Natural Cycle Assisted Reproduction: A Key Option for Poor Responders through Luteal Phase Oocyte Retrieval

Background: Emergence of Luteal Phase Oocyte Retrieval (LuPOR) may revolutionize the practice regarding the time-sensitive nature of poor responders ascertaining a higher number of oocytes, in a shorter amount of time. This may be especially important in view of employing the approach of natural cycles for Poor Responders. We suggest the acronym LuPOR describing the clinical practice of luteal phase oocyte retrieval. The aim of the study is to offer insight regarding the identity of LuPOR, and highlight how this practice may improve management of the special subgroup of poor responders. Materials and Methods: The present retrospective observational clinical study includes the collection and statistical analysis of data from 136 poor responders who underwent follicular oocyte retrieval (FoPOR) and subsequent LuPOR in natural cycles, during their In Vitro Fertilization (IVF) treatment, from the time period of 2015 to 2018. All 136 participants were diagnosed with poor ovarian reserve (POR) according to Bologna criteria. The 272 cycles were categorized as follows: 136 natural cycles with only FoPORs (Control Group) and 136 natural cycles including both FoPORs and LuPORs. Results: Our primary results indicate no statistically significant differences with regards to the mean number of oocytes, the maturation status, and fertilization rate between FoPOR and LuPOR in natural cycles. Secondarily, we demonstrate a statistically significant higher yield of oocytes (2.50 ± 0.78 vs. 1.25 ± 0.53), better oocyte maturity status (1.93 ± 0.69 vs. 0.95 ± 0.59) and higher fertilization rate (1.31 ± 0.87 vs. 0.61 ± 0.60) in natural cycles including both FoPOR and LuPOR, when compared to cycles including only FoPOR. Conclusion: Our study may contribute towards the establishment of an efficient poor responders’ management through the natural cycle approach, paving a novel clinical practice and ascertaining the opportunity to employ oocytes and embryos originating from a luteal phase follicular wave.

Double stimulation in the same ovarian cycle (DuoStim) is an intriguing strategy to improve oocyte yield and the number of competent embryos in a short timeframe

Proper ovarian stimulation regimens are crucial for any patient undergoing in-vitro fertilization (IVF). However, maximizing the oocyte yield in advanced maternal age patients with poor or suboptimal response is still a challenge. In fact, no standard treatment has been outlined yet to manage these women. Across the last years, an improved efficiency of the IVF units via blastocyst culture, vitrification and reliable embryo selection approaches paved the way to the investigation of novel unconventional stimulation protocols, like double stimulation in a single ovarian cycle (DuoStim). DuoStim, by conjugating follicular phase stimulation (FPS) and luteal phase stimulation (LPS) in the same ovarian cycle, allows to maximize the number of oocytes obtained in a short timeframe, a precious outcome when we aim at shortening time to pregnancy. In this regard, LPS seems to contribute to conventional stimulation with more oocytes with a comparable competence as FPS, retrieved per ovarian cycle. Although any stimulation protocol which exploits anovulatory waves of follicular growth needs a thorough investigation, no evidence has been produced to question the safety of DuoStim, which to date represents the most intriguing strategy to treat poor prognosis in IVF.

Management Strategies for POSEIDON Groups 3 and 4

In the POSEIDON classification, patients belonging to groups 3 and 4 share the same common feature of a poor ovarian reserve which independently of age renders them at high risk of a poor reproductive outcome. Overall, POSEIDON groups 1-4 constitute approximately 47% of patients attending assisted reproductive technology (ART) treatment. With the increasing delay in childbearing, POSEIDON group 4 seems to increase in numbers now in some centers constituting more than 50% of the total POSEIDON population, whereas group 3 patients constitute approximately 10%. Both POSEIDON groups 3 and 4 patients require special attention as regards pre-treatment strategy, ovarian stimulation, adjuvant treatment, and ovulation trigger strategy in order to optimize the probability of having at least one euploid blastocyst for transfer. Although more evidence is needed, recent advances seem to have increased the reproductive outcomes in the poor prognosis patient. The key to success is individualization in all steps of ART treatment. Herein, we review the recent evidence for the management of POSEIDON groups 3 and 4.

Ovarian manipulation in ART: going beyond physiological standards to provide best clinical outcomes

Current knowledge on ovarian physiology has challenged the traditional concept of folliculogenesis, creating the basis for novel ovarian stimulation protocols in assisted reproduction technology. The purpose of this review was to evaluate the efficacy of novel clinical interventions that could aid clinicians in individualizing their protocols to patients' characteristics and personal situations. We conducted a literature review of the available evidence on new approaches for ovarian stimulation from both retrospective and prospective studies in the PubMed database. Here, we present some of the most important interventions, including follicle growth in the gonadotropin-independent and dependent stage, manipulation of estradiol production throughout ovarian stimulation, control of mid-cycle gonadotropin surges, and luteal phase support after different stimulation protocols and trigger agents. The latest research on IVF has moved physicians away from the classical physiology, allowing the development of new strategies to decouple organ functions from the female reproductive system and challenging the traditional concept of IVF.

Implantation rates subsequent to the transfer of embryos produced at different phases during double stimulation of poor ovarian responders

To compare the implantation capacity of embryos obtained at different phases of double stimulation (DS) of poor ovarian responders, 153 DS cycles were analysed retrospectively. As part of the DS protocol, antral follicles were stimulated continuously during both the follicular and luteal phases. Fresh embryos obtained in both phases were cryopreserved and transferred in the next artificial cycle. The mean number of oocytes retrieved, MII oocytes and zygotes with two pronuclei was significantly higher for collections during luteal-phase stimulation. Furthermore, the dose of exogenous gonadotropin administered was higher during the luteal phase. The rate of clinical pregnancy and embryo implantation increased progressively from pure follicular phase embryos to mixed embryos to pure luteal phase embryos. Embryos produced during the luteal phase resulted in higher implantation rates.

Double ovarian stimulation during the follicular and luteal phase in women ≥38 years: a retrospective case-control study

Previous studies have shown that double ovarian stimulation could obtain more oocytes in women with poor ovarian response. This retrospective case-control study aimed to investigate the efficacy of double ovarian stimulation in older women. One hundred and sixteen women aged ≥38 years who received double ovarian stimulation were assigned to the study, with 103 divided into four groups according to follicular-phase ovarian stimulation protocols, including gonadotrophin-releasing hormone agonist short protocol (n = 27), gonadotrophin-releasing hormone antagonist protocol (n = 32), mild stimulation protocol (n = 21) and medrocyprogesterone acetate (MPA) pituitary down-regulation protocol (n = 23). Numbers of oocytes retrieved and available embryos after double ovarian stimulation were more than double those obtained after follicular-phase ovarian stimulation alone. In total 81.90% of patients had available embryos, and the cancellation rate decreased from 37.07% to 18.10%. Forty-eight cases underwent 50 cryopreserved embryo transfer cycles, with a 22.00% clinical pregnancy rate. The implantation rate (10.53% versus 10.67%) was similar between the embryos derived from first and second stimulations. The results suggest that double ovarian stimulation could increase the chances of achieving pregnancy by accumulating more oocytes/embryos in a short time, which might serve as a useful strategy for older women.

Luteal-phase protocol in poor ovarian response: a comparative study with an antagonist protocol

Objective

This retrospective study compared the effect of the luteal phase ovarian stimulation protocol (LP group) with the gonadotrophin-releasing hormone (GnRH) antagonist protocol (AN group) in women with poor ovarian responses.

Methods

Ovarian stimulation was initiated with 225 IU of human gonadotrophin (hMG) daily. When the dominant follicle diameter exceeded 13 mm, 0.25 mg of a GnRH antagonist was used daily until human chorionic gonadotrophin (HCG) administration in the AN group. A GnRH antagonist was not used in the LP group. Ovulation was induced with HCG for all patients when at least one follicle reached a diameter of 16 mm or one dominant follicle reached 18 mm. The highest quality embryos were transferred or cryopreserved for later transfer.

Results

From January 2013 to December 2015, 274 women with poor ovarian response were included. A total of 108 patients underwent the luteal phase ovarian stimulation protocol while 166 patients underwent the GnRH antagonist protocol. hMG was used for more total days in the LP group was than in the AN group. Oestradiol levels on the day of HCG administration in the LP group were significantly lower than those in the AN group. The mean number of oocytes retrieved in the LP and AN groups was 3.5 ± 2.5 and 3.5 ± 2.9, respectively. The mean number of embryos of the highest quality was 1.7 ± 1.2 and 1.7 ± 1.5, respectively. The clinical pregnancy and implantation rates in the LP and AN groups were 26.2% (22/84) and 25% (29/116), and 15.5% (24/155) and 16.3% (35/215), respectively.

Conclusions

The luteal phase ovarian stimulation protocol can be applied in women with poor ovarian response and attain comparable clinical pregnancy and implantation rates to those of the GnRH antagonist protocol.

Comparison between follicular stimulation and luteal stimulation protocols with clomiphene and HMG in women with poor ovarian response

This retrospective study is to compare the follicular mild stimulation and luteal simulation protocols for poor responders undergoing in vitro fertilization (IVF). A total of 131 women were diagnosed as poor responders. Thirty-three women started ovarian stimulation in early-luteal phase and 98 women started in early follicular phase with 100 mg/d clomiphene citrate and 75-150 IU/d HMG. There were more oocytes retrieved (2.8 ± 2.0 versus 2.0 ± 1.2, p < 0.05), more available embryos (1.8 ± 1.4 versus 1.3 ± 1.1, p < 0.05) and top-quality embryos (0.9 ± 0.9 versus 0.4 ± 0.6, p < 0.05), and reduced cycle cancellation rate (12.1% versus 30.6%, p < 0.05) in luteal group than in follicular group. The clinical pregnancy (17.7%, 20.0% and 41.2%) and live-birth rates (10.78%, 20.0% and 29.4%) after transferring embryos obtained from luteal, follicular and mixed stages were comparable (p > 0.05). For poor responders, luteal phase stimulation could be an option because of increasing the chance to obtain competent embryos and reducing the cycle cancellation rate.