Comparison of ovarian stimulation response in patients with breast cancer undergoing ovarian stimulation with letrozole and gonadotropins to patients undergoing ovarian stimulation with gonadotropins alone for elective cryopreservation of oocytes†

Changing the Perspective on Fertility Preservation for Women with Metastatic or Advanced Stage Cancer

PURPOSE OF REVIEW

In this Perspective we share the personal story of a 33-year-old patient diagnosed with metastatic breast cancer and her journey through fertility preservation, surrogacy, and eventually motherhood, highlighting misconceptions about fertility preservation in this population.

RECENT FINDINGS

There are nearly 1 million women under the age of 50 diagnosed and living with cancer in the USA. These patients are met with life-altering decisions, including those that may limit their reproductive ability. While there have been tremendous advances and advocacy in the field of oncofertility, there has been limited focus on patients with advanced stage or metastatic cancer. We describe five key misconceptions surrounding fertility preservation in patients with advanced stage cancer, offering a review of the literature and our approach to challenging topics like desiring fertility preservation in the face of Stage 4 disease, the safety and timing of ovarian stimulation during cancer treatment, and passing away following fertility preservation. We review the importance of assessing perceptions of fertility preservation in patients with metastatic cancer and highlight the lack of research in this area as a call to action.

Reassessing the impact of letrozole co-administration in controlled ovarian hyperstimulation: findings from a single-center repeated measures study

PURPOSE

To explore whether letrozole improved outcomes in subsequent controlled ovarian hyperstimulation (COH) cycles.

METHODS

This was a retrospective repeated measures cohort study examining COH cycles. Patients were included if they underwent two cycles for unexplained infertility, male factor infertility, or planned oocyte/embryo cryopreservation. The first cycles for all patients implemented a non-letrozole, conventional gonadotropin protocol. Second cycles for the study group included letrozole (2.5-7.5 mg for 5 days) with no medication change to second cycles amongst controls. Our primary objective was to compare oocyte yield. Cohorts were then subdivided by pursuit of oocyte (OC) or embryo (IVF) cryopreservation. Secondary outcome amongst the OC subgroup was oocyte maturation index (metaphase II (MII)/total oocytes). Secondary outcomes amongst the IVF subgroup were normal fertilization rate (2-pronuclear zygotes (2PN)/oocytes exposed to sperm), blastocyst formation rate (blastocysts/2PNs), and embryo ploidy (%euploid and aneuploid).

RESULTS

Fifty-four cycles (n = 27) were included in letrozole and 108 cycles (n = 54) were included in control. Oocyte yield was higher in second cycles (p < 0.008) in the letrozole group but similar in second cycles (p = 0.26) amongst controls. Addition of letrozole did not impact MII index (p = 0.90); however, MII index improved in second cycles amongst controls (p < 0.001). Both groups had similar rates of normal fertilization (letrozole: p = 0.52; control: p = 0.61), blast formation (letrozole: p = 0.61; control: p = 0.84), euploid (letrozole: p = 0.29; control: p = 0.47), and aneuploid embryos (letrozole: p = 0.17; control: p = 0.78) between cycles.

CONCLUSIONS

Despite improved oocyte yield, letrozole did not yield any difference in oocyte maturation or embryo outcomes.

Impact of 2.5 mg versus 5 mg letrozole co-treatment in an antagonist protocol for IVF: a retrospective study

Objective

The present study aimed to compare the effectiveness of two different doses of letrozole (2.5 mg and 5 mg daily) in an antagonist protocol for infertile women with normal ovarian reserve.

Methods

This retrospective cohort study included infertile women who underwent in vitro fertilization treatment with letrozole co-treatment at doses of 2.5 mg and 5 mg from 2007 - 2021 at Shanghai Ninth People's Hospital (Shanghai, China). The control group comprised infertile women who received gonadotropin-releasing hormone antagonist alone. The primary outcome was the cumulative live birth rate, while secondary outcomes included follicular phase endocrine parameters, ovarian stimulation outcomes, pregnancy outcomes, and the incidences of maternal and neonatal complications. Baseline and follow-up data were compared between the groups using ANOVA for normally distributed variables, the Kruskal-Wallis test for non-normally distributed variables, and the Chi-square test for categorical variables.

Results

A total of 422 participants were enrolled in the study, with 211 women in the antagonist group, 109 women in the 2.5 mg letrozole co-treatment group, and 102 women in the 5 mg letrozole co-treatment group. Letrozole co-treatment significantly suppressed oestradiol and follicle-stimulating hormone concentrations from stimulation day 5 and onwards, while increasing luteinizing hormone levels on stimulation day 5 and trigger day. The effect was more pronounced with a 5 mg dose of letrozole compared to a 2.5 mg dose (P < 0.05). Administration of 5 mg letrozole reduced the gonadotropin dose (P < 0.05) without negatively affecting the number of oocytes retrieved and subsequent embryo parameters (P > 0.05). The analysis of cumulative live birth rates showed rates of 29.4% in the letrozole 5 mg group, 27.5% in the letrozole 2.5 mg group, and 33.6% in the control group, with no statistically significant difference (P > 0.05). There were no reported pregnancy complications in the two letrozole groups. Additionally, there were no significant differences among the three groups in terms of gestational age and birth weight for both singleton and twin births.

Conclusion

This study indicates that the administration of letrozole in an antagonist protocol, at both 2.5 mg and 5 mg dosages, results in comparable clinical outcomes.

Low-grade serous ovarian cancer: expert consensus report on the state of the science

Compared with high-grade serous carcinoma, low-grade serous carcinoma of the ovary or peritoneum is a less frequent epithelial ovarian cancer type that is poorly sensitive to chemotherapy and affects younger women, many of whom endure years of ineffective treatments and poor quality of life. The pathogenesis of this disease and its management remain incompletely understood. However, recent advances in the molecular characterization of the disease and identification of novel targeted therapies with activity in low-grade serous carcinoma offer the promise of improved outcomes. To update clinicians regarding recent scientific and clinical trial advancements and discuss unanswered questions related to low-grade serous carcinoma diagnosis and treatment, a panel of experts convened for a workshop in October 2022 to develop a consensus document addressing pathology, translational research, epidemiology and risk, clinical management, and ongoing research. In addition, the patient perspective was discussed. The recommendations developed by this expert panel-presented in this consensus document-will guide practitioners in all settings regarding the clinical management of women with low-grade serous carcinoma and discuss future opportunities to improve research and patient care.

Fertility preservation, its effectiveness and its impact on disease status in pre-menopausal women with breast cancer: A systematic review and meta-analysis

INTRODUCTION

Preservation of reproductive function is a key concern for many premenopausal women with breast cancer, given the known gonadotoxic effects of treatments. The present systematic review aimed to investigate the effectiveness and safety of fertility preservation strategies in pre-menopausal women with breast cancer.

METHODS

Primary research assessing fertility preservation strategies of any type was identified. Markers of preservation of fertility including return of menstrual function, clinical pregnancy rates and live birth rates were selected as main outcome measures. An additional analysis of safety data was also performed.

RESULTS

Fertility preservation interventions were overall associated with higher fertility outcomes: with a pooled odds ratio 4.14 (95% CI 3.59-4.77) for any kind of fertility preservation intervention. This was seen both for return of menstruation and for clinical pregnancy rate, but not for live birth rates. Fertility preservation was associated with a reduced rate of disease recurrence (OR 0.63 (95% CI 0.49-0.81)), while there was no significant difference in disease free survival (OR 0.88 (95% CI 0.74-1.05)) or in overall survival (OR 0.9 (95% CI 0.74-1.10)) between the fertility preservation group and those who had not undergone fertility preservation.

CONCLUSION

Fertility preservation is both effective in preserving reproductive function, and safe with regard to disease recurrence, disease free survival and overall survival in premenopausal women with breast cancer.

Ovarian reserve in reproductive-aged patients with cancer before gonadotoxic treatment: a systematic review and meta-analysis

STUDY QUESTION

Does cancer itself, before any gonadotoxic treatment, affect ovarian function in reproductive-aged patients?

SUMMARY ANSWER

Our study revealed that women with cancer may have decreased ovarian reserve markers even before cancer therapy.

WHAT IS KNOWN ALREADY

With the field 'oncofertility' improving rapidly, cancer therapy-mediated ovarian damage is well characterized. However, there is a controversy about whether cancer itself affects ovarian function before gonadotoxic treatment.

STUDY DESIGN SIZE DURATION

We conducted a systematic meta-analysis investigating the association between cancer and ovarian function prior to gonadotoxic treatment. Titles or abstracts related to ovarian reserve (e.g. anti-Müllerian hormone (AMH), antral follicle count (AFC), or basal follicle-stimulating hormone (FSH)) combined with titles or abstracts related to the exposure (e.g. cancer*, oncolog*, or malignan*) were searched in PubMed, Embase, and Web of Science databases from inception to 1 February 2022.

PARTICIPANTS/MATERIALS SETTING METHODS

We included cohort, case-control, and cross-sectional studies in English that examined ovarian reserve in reproductive-aged patients (18-45 years) with cancer compared to age-matched controls before cancer treatment. The quality of the included studies was assessed by ROBINS-I. Fixed or random effects were conducted to estimate standard or weighted mean difference (SMD or WMD, respectively) and CI. Heterogeneity was assessed by the Q test and I² statistics, and publication bias was evaluated by Egger's and Begg's tests.

MAIN RESULTS AND THE ROLE OF CHANCE

The review identified 17 eligible studies for inclusion. The results showed that cancer patients had lower serum AMH levels compared to healthy controls (SMD = -0.19, 95% CI = -0.34 to -0.03, P = 0.001), especially women with hematological malignancies (SMD = -0.62, 95% CI = -0.99 to -0.24, P = 0.001). The AFC was also decreased in patients with cancer (WMD = -0.93, 95% CI = -1.79 to -0.07, P = 0.033) compared to controls, while inhibin B and basal FSH levels showed no statistically significant differences.

LIMITATIONS REASONS FOR CAUTION

Serum AMH and basal FSH levels in this meta-analysis showed high heterogeneity, and the small number of studies contributing to most subgroup analyses limited the heterogeneity analysis. Moreover, the studies for specific cancer subtypes may be too small to draw conclusions; more studies are needed to investigate the possible impact of cancer type and stage on ovarian function.

WIDER IMPLICATIONS OF THE FINDINGS

Our study confirmed the findings that cancer per se, especially hematological malignancies, negatively affects serum AMH level, and AFC values of reproductive-aged women. However, the lower AMH levels and AFC values may also be due to the changes in ovarian physiology under oncological conditions, rather than actual lower ovarian reserves. Based on the meta-analysis, clinicians should raise awareness about the possible need for personalized approaches for young women with cancer who are interested in pursuing fertility preservation strategies before anticancer treatments.

STUDY FUNDING/COMPETING INTERESTS

This work was financially supported by the National Natural Science Foundation of China (nos 81873824, 82001514, and 81902669) and the Applied Basic Research Program of Wuhan Municipal Bureau of Science and Technology (2019020701011436). The authors declare that they have no conflicts of interest.

REGISTRATION NUMBER

PROSPERO (CRD42021235954).

Outcomes after assisted reproductive technology in women with cancer: a systematic review and meta-analysis

STUDY QUESTION

What are the associations between a history of cancer and outcomes after ART?

SUMMARY ANSWER

Compared to women without cancer, on average, women with cancer had a lower return for embryo transfer and a lower likelihood of clinical pregnancy and live birth after ART.

WHAT IS KNOWN ALREADY

Small, single-institution studies have suggested that cancer and its treatment may negatively affect ART outcomes.

STUDY DESIGN, SIZE, DURATION

We conducted a systematic review with meta-analysis of studies comparing ART outcomes between women with and without cancer. PubMed, Embase and Scopus were searched for original, English-language studies published up to June 2021.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Inclusion criteria required reporting of ART outcomes after controlled ovarian stimulation (COS) among women with a history of cancer compared to women without cancer who used ART for any indication. Outcomes of interest ranged from duration of COS to likelihood of live birth after embryo transfer. Random-effects meta-analysis was used to calculate mean differences and odds ratios (ORs) with 95% CIs and 95% prediction intervals (PIs). We assessed heterogeneity by age-adjustment, referent group indication for ART, study location and among women with breast cancer and women who initiated ART before cancer treatment. We used visual inspection, Egger's test and the trim-and-fill method to assess funnel plot asymmetry.

MAIN RESULTS AND THE ROLE OF CHANCE

Of 6094 unique records identified, 42 studies met inclusion criteria, representing a median per study of 58 women with cancer (interquartile range (IQR) = 159) and 114 women without cancer (IQR = 348). Compared to women without cancer, on average, women with cancer had a lower return for embryo transfer (OR: 0.22; 95% CI: 0.07, 0.74; 95% PI: 0.00, 64.98); lower likelihood of clinical pregnancy (OR: 0.51; 95% CI: 0.35, 0.73; 95% PI: 0.19, 1.35); and lower likelihood of live birth (OR: 0.56; 95% CI: 0.38, 0.83; 95% PI: 0.19, 1.69). Substantial among-study heterogeneity was observed for COS duration, gonadotropin dose, cycle cancellation, total oocytes and mature oocytes. Fertilization percentage showed less heterogeneity, but study-specific estimates were imprecise. Similarly, number of embryos showed less heterogeneity, and most studies estimated minimal differences by cancer history. Funnel plot asymmetry was observed for estradiol peak and oocyte maturation percentage.

LIMITATIONS, REASONS FOR CAUTION

Appreciable confounding is possible in 11 studies that lacked adequate control for group differences in age, and among-study heterogeneity was observed for most outcomes. Lack of data limited our ability to assess how cancer clinical factors (e.g. cancers other than breast, cancer stage and treatment) and ART cycle characteristics (e.g. fresh versus frozen embryo transfers and use of gestational carriers) may affect outcomes.

WIDER IMPLICATIONS OF THE FINDINGS

Women with cancer may be less likely to achieve pregnancy and live birth after embryo transfer. Further examination of reproductive outcomes and sources of heterogeneity among studies is warranted to improve evidence of the expected success of ART after a cancer diagnosis.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported in part by R01 CA211093 and P30 ES010126. C.M. was supported by the University of North Carolina Lineberger Cancer Control Education Program (T32 CA057726) and the National Cancer Institute (F31 CA260787). J.A.R.-H. was supported by the National Cancer Institute (K08 CA234333, P30 CA016672). J.A.R.-H. reports receiving consulting fees from Schlesinger Group and Guidepoint. The remaining authors declare no competing interests.

REGISTRATION NUMBER

N/A.

The impact of letrozole on oocyte quality in assisted reproductive technology (ART); a randomized double-blind clinical trial

OBJECTIVE

To examine the effect of letrozole on oocyte quality and pregnancy outcome in assisted reproductive technology (ART).

METHODS

This double blind placebo controlled clinical trial was conducted in Vali-Asr Infertility Center. Infertile women candidate for IVF that underwent antagonist protocol were selected. Eligible women randomly allocated into treatment (letrozole/Let group) and control (placebo) group. Participants received letrozole 5 mg/day or placebo at the time of gonadotropin start until trigger day in the same manner. Number of oocyte retrieved, metaphase II oocyte number, high grade oocyte number (G1), high quality embryo, Chemical and clinical pregnancy rate and OHSS (ovarian hyperstimulation syndrome) rate was recorded. 216 infertile women (104 in letrozole and 112 in the control group) were evaluated.

RESULTS

In the Let group estradiol level was significantly lower (p_value < .001) and testosterone significantly higher than in the control group (p_value = .02). The number of retrieved oocytes, MII oocytes, G1 oocytes, and 2PN was significantly lower in the Let group (p < .05). No significant difference was found in the day of stimulation, total gonadotropin dose, OHSS rate, and clinical pregnancy rate between the two groups (p > 0.05).

CONCLUSIONS

According to the results, letrozole may reduce oocyte quality and cause poor IVF outcomes as well.

A Review on the Use of Letrozole in Female and Male Infertility

Infertility in developing countries is a distinct and complex problem that disproportionately affects women. Though not a physically restraining disease, it causes a huge social burden on the emotional, financial, and psychosocial quotients of those who suffer from it. Assisted reproductive procedures are frequently used to treat infertility. Years ago, the emergence of ovulation induction represented a significant advancement in treating female infertility. Letrozole, an aromatase inhibitor, is a potential therapy for ovulation induction. Numerous clinical conditions, including anovulatory infertility, polycystic ovarian syndrome, unexplained infertility, and early stages of endometriosis-related infertility, as well as many with improved live birth rates, have been proven to benefit from letrozole treatment. Letrozole is a superior alternative to the widely utilized ovulation induction with clomiphene citrate. While clomiphene citrate has certain limitations, letrozole successfully overcomes these limitations because of its lack of prolonged anti-estrogenic activity, short half-life, and lack of estrogen receptor activation. In most cases, this results in mono-follicular development and excellent live birth rates. According to the most recent research, letrozole can be used as the first-line therapy to treat infertility caused by polycystic ovarian syndrome and other causes. Letrozole is also emerging as a possible treatment for male infertility of unknown cause, proving to be an effective way of influencing hormonal profiles and increasing various seminal parameters such as sperm motility and concentration, as it inhibits aromatization affecting the feedback mechanism to the hypothalamus. This review focuses on our current knowledge of the uses of letrozole for female and male infertility, its mechanisms, and its benefits.

What should be done in terms of fertility preservation for patients with cancer? The French 2021 guidelines

AIM

To provide practice guidelines about fertility preservation (FP) in oncology.

METHODS

We selected 400 articles after a PubMed review of the literature (1987-2019).

RECOMMENDATIONS

Any child, adolescent and adult of reproductive age should be informed about the risk of treatment gonadotoxicity. In women, systematically proposed FP counselling between 15 and 38 years of age in case of treatment including bifunctional alkylating agents, above 6 g/m2 cyclophosphamide equivalent dose (CED), and for radiation doses on the ovaries ≥3 Gy. For postmenarchal patients, oocyte cryopreservation after ovarian stimulation is the first-line FP technique. Ovarian tissue cryopreservation should be discussed as a first-line approach in case of treatment with a high gonadotoxic risk, when chemotherapy has already started and in urgent cases. Ovarian transposition is to be discussed prior to pelvic radiotherapy involving a high risk of premature ovarian failure. For prepubertal girls, ovarian tissue cryopreservation should be proposed in the case of treatment with a high gonadotoxic risk. In pubertal males, sperm cryopreservation must be systematically offered to any male who is to undergo cancer treatment, regardless of toxicity. Testicular tissue cryopreservation must be proposed in males unable to cryopreserve sperm who are to undergo a treatment with intermediate or severe risk of gonadotoxicity. In prepubertal boys, testicular tissue preservation is: - recommended for chemotherapy with a CED ≥7500 mg/m2 or radiotherapy ≥3 Gy on both testicles. - proposed for chemotherapy with a CED ≥5.000 mg/m2 or radiotherapy ≥2 Gy. If several possible strategies, the ultimate choice is made by the patient.

Effect of letrozole on follicular fluid steroids concentrations in cancer patients undergoing oocytes cryopreservation

PURPOSE

To investigate the impact of letrozole administration on follicular steroid hormones during controlled ovarian hyperstimulation for fertility preservation.

METHODS

One hundred and nineteen women with cancer undergoing oocytes retrieval for fertility preservation were recruited. All women underwent ovarian hyperstimulation according to a random start protocol. Those with hormone-sensitive tumors also received letrozole, an aromatase inhibitor aimed at keeping peripheral estrogen levels low. At the time of oocytes retrieval, a sample of follicular fluid was collected and frozen. All samples were assayed concomitantly after thawing, by liquid chromatography tandem mass spectrometry. The concentration of 15 steroid hormones was determined and results were compared between women who did and did not receive letrozole.

RESULTS

Fifty-two women were treated with letrozole, while 67 were not. Statistically significant differences emerged for 12 of the 15 tested steroids. They were the following: cortisol, 11-deoxycortisol, 21-deoxycortisol, dehydroepiandrosterone sulfate (DHEAS), dehydroepiandrosterone (DHEA), estradiol, androstenedione, testosterone, dihydrotestosterone (DHT), 17-hydroxyprogesterone, progesterone and corticosterone. The most striking differences were observed for testosterone that showed a more than 200-time increase in women receiving letrozole. Estradiol was conversely reduced to a third.

CONCLUSIONS

The endocrine microenvironment surrounding oocytes is markedly perturbed by the concomitant assumption of letrozole. Robust clinical evaluation is pressingly needed to rule out any detrimental effect on the chance of live birth with the use of these oocytes.

Efficacy and safety of controlled ovarian stimulation using GnRH antagonist protocols for emergency fertility preservation in young women with breast cancer-a prospective nationwide Swedish multicenter study

STUDY QUESTION

How efficacious and safe are the current approaches to controlled ovarian stimulation (COS) aimed at fertility preservation (FP) in women with breast cancer (BC)?

SUMMARY ANSWER

In women with BC undergoing COS aiming at egg/embryo cryopreservation, letrozole-based protocols and those randomly started were equally effective compared with conventional COS, and the overall survival was similar between the women that proceeded to FP and those who did not.

WHAT IS KNOWN ALREADY

Cryopreservation of oocytes and embryos is an established method for FP in women with BC. Recent improvements to COS protocols include concomitant use of letrozole, random-cycle start day of stimulation and the use of GnRHa for the egg maturation trigger. To date, limited sample size of the available studies has not allowed investigation of differences in the efficacy of the different approaches to COS for FP in this patient population.

STUDY DESIGN, SIZE, DURATION

A prospective multicenter study with national coverage including 610 women with BC counseled between 1 January 1995 and 30 June 2017 at six Swedish FP regional programs.

PARTICIPANTS/MATERIALS, SETTING, METHODS

After counseling, 401 women elected to undergo COS. Treatments differed in the use or not of concomitant letrozole, a conventional or random-cycle day COS initiation and the use of hCG versus GnRHa trigger for oocyte maturation. Numbers of cryopreserved oocytes and embryos were defined as primary outcome. Pregnancy attempts, reproductive outcomes and long-term survival, investigated by the linking of individuals of the cohort to the total population register of the Swedish Tax Agency (up to 25 November 2018), were evaluated.

MAIN RESULTS AND THE ROLE OF CHANCE

Using letrozole or not resulted in similar numbers of oocytes and embryos cryopreserved (mean_oocytes = 9.7 versus 10 and mean_embryos 4.0 versus 5.3, respectively), similar to COS with random versus conventional start (mean_oocytes 9.0 versus 10.6 and mean_embryos 4.8 versus 4.8). In COS with letrozole, a GnRHa trigger was associated with a higher number of oocytes retrieved (P < 0.05) and embryos cryopreserved (P < 0.005), compared with conventional hCG trigger. Of 99 women who returned to fertility clinics after cancer treatment, 32 proceeded to thawing of oocytes or embryos and 10 of them had live births. The all-cause survival between the women that underwent COS and those who did not was similar and did not differ between the two groups.

LIMITATIONS, REASONS FOR CAUTION

Data on tumor characteristics and estrogen receptor (ER) status were not known for all women at the time of FP counseling and planning of COS, thus protocols with letrozole have been used for both estrogen-sensitive and non-estrogen-sensitive BC. For the same reason, subsequent adjustment for ERs in the BC or tumor characteristics as potential confounders were not performed as these parameters were not available and did not influence the provision of FP through COS.

WIDER IMPLICATIONS OF THE FINDINGS

The results of our study support the premise that recently introduced potential improvements to COS protocols for FP in women with BC are efficacious and safe.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by research grants from the Swedish Cancer Society, the Stockholm County Council, the Percy Falk Stiftelsen, Radiumhemmets Forskningsfonder, The Swedish Breast Cancer Association and Karolinska Institutet to K.A.R.W. J.B. reports grants from Amgen, AstraZeneca, Pfizer, Roche, Sanofi-Aventis and Merck, outside the submitted work, and payment from UpToDate to Asklepios Medicine HB for a chapter on BC prediction and prognostication. All the other authors have no competing interests to report.

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.

Ovulatory-Based FET Cycles May Achieve Higher Pregnancy Rates in the General Population and among Anovulatory Women

This study evaluated which endometrial preparation protocol in frozen embryo transfer (FET) cycles provides the best results for polycystic ovarian syndrome (PCOS) patients and the general population. This retrospective study of 634 FET cycles was conducted 2016-2018. Cycles were divided into Group A: Artificial endometrial preparations for FET (aFET; n = 348), Group B: Ovulatory cycle (n = 286) to compare two methods of endometrial preparation for FET. Artificial endometrial preparation with exogenous estrogen and progesterone versus natural ovulation cycles, modified natural cycles using hCG for the final triggering and letrozole-induced ovulation with hCG. Anovulatory patients were analyzed separately. Anovulatory PCOS patients had significantly higher pregnancy rates with letrozole treatment compared with aFET cycles (44% vs. 22.5%; p = 0.044). For the entire cohort, ovulatory cycles and aFET were similar in terms of patient characteristics, demographics, infertility causes, treatment protocols and number of embryos transferred. Although the mean ESHRE score of the transferred embryos was higher in the aFET group, we found higher clinical pregnancy rate in the ovulatory cycle FET (41.3% vs. 27.3%, p < 0.0001). A better pregnancy rate was found after ovulatory cycle FET. In the ovulatory cycles, the outcome of letrozole-induced and non-induced cycles were comparable. PCOS patients, as well as the general population, may benefit from ovulation induced FET cycles, with significantly better outcomes in FET in ovulatory cycles.

The Effects of Negative Elements in Environment and Cancer on Female Reproductive System

With the development of human society, factors that contribute to the impairment of female fertility is accumulating. Lifestyle-related risk factors, occupational risk factors, and iatrogenic factors, including cancer and anti-cancer treatments, have been recognized with their negative effects on the function of female reproductive system. However, the exact influences and their possible mechanism have not been elucidated yet. It is impossible to accurately estimate the indexes of female fertility, but many researchers have put forward that the general fertility has inclined through the past decades. Thus the demand for fertility preservation has increased more and more dramatically. Here we described some of the factors which may influence female reproductive system and methods for fertility preservation in response to female infertility.

Letrozole for Female Infertility

Letrozole, an aromatase inhibitor that blocks estrogen synthesis by inhibiting the final step of the estrogen biosynthetic pathway, has been used in the applications of a wide range of infertility settings. It has been more than 20 years since the initial clinical trial of letrozole for ovulation induction. In light of the accumulating clinical and basic evidence, the efficacy and safety of letrozole have been identified. This mini review focuses on our current knowledge of the applications and mechanisms of letrozole for female infertility and various questions are put forward about how letrozole could be more effectively used.

Predictor for supraphysiologic serum estradiol elevation on hCG triggering day of controlled ovarian stimulation using letrozole and gonadotropins in women with estrogen-dependent cancers

The objective of this study was to evaluate predicting factors for supraphysiologic serum estradiol elevation during controlled ovarian stimulation (COS) with administration of letrozole and gonadotropins in patients with estrogen-dependent cancer. Use of aromatase inhibitors is recommended to prevent the potential effects of elevated serum estradiol levels and recurrence of tumor in patients with estrogen-dependent cancers during COS. Although previous studies reported that letrozole have shown an effective lowering of peak estrogen levels, a part of patients shows supraphysiologic levels of estrogen associated with ovarian stimulation despite the administration of letrozole. From January 2009 to December 2019, patients with estrogen-dependent cancer who underwent COS with antagonist protocol using a letrozole (5 mg/ day) to keep estrogen levels low were included in this study. Early monitoring serum estradiol was measured in all patients on the 4-6th day of stimulation. Subjects were classified into two groups according to the serum estradiol level on hCG triggering day, physiologic estradiol group (≤400 pg/mL) and supraphysiologic estradiol group (>400 pg/mL). A total of 96 COS cycles were retrospectively analyzed. Supraphysiologic level of serum estradiol was found in 21.9% of the patients. Mean age, AMH, duration of stimulation, total dose of gonadotropins administered were not different between the two groups. However, early monitoring serum estradiol level was significantly higher in the supraphysiologic estradiol group (67.1±47.9 vs. 115.6±78.1, p = 0.001) and was associated with the occurrence of supraphysiologic elevation of serum estradiol on hCG triggering day. Patients with early monitoring serum estradiol ≥84.5 pg/mL had an odds ratio of 5.376 [95% CI, 1.613–17.913] for supraphysiologic elevation of serum estradiol compared to those with early monitoring serum estradiol below 84.5 pg/mL. In conclusion, early monitoring serum estradiol is an independent predicting factor for supraphysiologic level of serum estradiol on hCG triggering day in the COS cycles using letrozole and gonadotropins.

Efficacy and Safety of Controlled Ovarian Stimulation With or Without Letrozole Co-administration for Fertility Preservation: A Systematic Review and Meta-Analysis

Background: The co-administration of letrozole during controlled ovarian stimulation (COS) with gonadotropins is used to limit the potentially harmful effects of a supra-physiological rise in estrogen levels on hormone-sensitive cancers. However, the efficacy and safety of adding letrozole to COS remain debated.

Methods: This is a systematic review and meta-analysis of published studies that compared the efficacy and safety of COS with co-administration of letrozole vs. COS without letrozole in all patient populations. A secondary analysis was done including only the studies in breast cancer patients. The primary efficacy endpoint was the number of retrieved mature Metaphase II (MII) oocytes. Secondary efficacy and safety endpoints were total number of oocytes, maturation rate, fertilization rate, number of cryopreserved embryos, peak estradiol levels, progesterone levels, and total gonadotropin dose. Data for each endpoint were reported and analyzed thorough mean ratio (MR) with 95% confidence interval (CI).

Results: A total of 11 records were selected including 2,121 patients (990 patients underwent COS with letrozole and 1,131 COS without letrozole). The addition of letrozole to COS did not have any negative effect on the number of mature oocytes collected (MR = 1.00, 95% CI = 0.87–1.16; P = 0.967) and the other efficacy endpoints. COS with letrozole was associated with significantly decreased peak estradiol levels (MR = 0.28, 95% CI = 0.24–0.32; P < 0.001). Similar results were observed in the secondary analysis including only breast cancer patients.

Conclusions: These findings are reassuring on the efficacy and safety of COS with gonadotropins and letrozole and are particularly important for fertility preservation in women with hormone-sensitive cancers.

Does daily co administration of gonadotropins and letrozole during the ovarian stimulation improve IVF outcome for poor and sub optimal responders?

Background

Co-administration of letrozole during the first 5 days of ovarian stimulation was suggested to improve IVF outcomes in poor responders. We aimed to determine whether poor/sub-optimal responders might benefit from Letrozole co-treatment throughout the entire stimulation course.

Methods

We retrospectively reviewed the medical files of women who demonstrated poor (oocyte yield ≤3) and sub-optimal (4 ≤ oocyte yield ≤9) ovarian response during conventional multiple-dose antagonist stimulation protocols and were co-treated in a subsequent cycle with 5 mg Letrozole from the first day of stimulation until trigger day. A self-paired comparison between gonadotropins-only and gonadotropins-letrozole cycles was performed.

Results

Twenty-four patients were included. Mean patients’ age was 39.83 ± 4.60 and mean day-3-FSH was 12.77 ± 4.49 IU/m. Duration of stimulation and total gonadotropins dose were comparable between the two cycle groups. Peak estradiol levels were significantly lower in gonadotropins-letrozole cycles (2786.74 ± 2118.53 vs 1200.13 ± 535.98, p < 0.05). Number of retrieved oocytes (3.29 ± 2.15 vs 6.46 ± 3.20, p < 0.05), MII-oocytes (2.47 ± 1.65 vs 5.59 ± 3.20, p < 0.05), 2PN-embryos (1.78 ± 1.50, 4.04 ± 2.74, p < 0.05) and top-quality embryos (0.91 ± 0.97 vs. 2.35 ± 1.66, p < 0.05) were significantly higher in the gonadotropins-letrozole cycles. Clinical pregnancy rate in gonadotropins-letrozole cycles was 31.5%.

Conclusion

Letrozole co-treatment during the entire stimulation course improves ovarian response and IVF outcomes in poor/sub-optimal responders.

Effect of adding letrozole to gonadotropin on in vitro fertilization outcomes: An RCT

Background

Aromatase inhibitors prevent the aromatization of androgens into estrogens, which reduces the negative feedback of estrogen on the hypothalamic-pituitary axis. It is clear that increasing the secretion of follicle-stimulating hormones results in an increased follicular growth.

Objective

This study aimed to evaluate the effect of adding letrozole to gonadotropin on in vitro fertilization outcomes in normal responders.

Materials and Methods

In this randomized clinical trial, 100 normal responder women candidate for controlled ovarian stimulation were randomly enrolled in two groups (n = 50/each). In the case group letrozole was added to gonadotropin in the antagonist protocol. The control group received the conventional antagonist protocol. The main outcome was clinical and chemical pregnancy; and the second outcomes were the number of mature oocytes, the fertilization rate, estradiol level, and the total dose of gonadotropins.

Results

Basic clinical and demographic features were comparable between the groups. Estradiol level on the day of human-chorionic-gonadotropin administration and the total gonadotropin consumption were significantly higher in the control group than the case group (p = 0.045). In addition, the number of MII oocytes was higher (but not significantl) in the case group than the control group (p = 0.09). Moreover, the endometrial thickness was significantly lower in the case group. There were no significant differences in fertilization rate and chemical and clinical pregnancy rates between the two groups.

Conclusion

Although adding letrozole to gonadotropin in normal responders reduces the total dose of gonadotropin, it does not improve the pregnancy outcomes.

Effect of ovarian stimulation on the expression of piRNA pathway proteins

PIWI-interacting RNAs (piRNAs) play an important role in gametogenesis, fertility and embryonic development. The current study investigated the effect of different doses of pregnant mare serum gonadotrophin/human chorionic gonadotrophin (PMSG/hCG) and repeated ovarian stimulation (OS) on the expression of the Mili, Miwi, Mael, Tdrd1, Tdrd9, qnd Mitopld genes, which have crucial roles in the biogenesis and function of piRNAs. Here, we found that after treatment with 7.5 I.U. PMSG/hCG and two repeated rounds of OS, both the mRNA and protein levels of Tdrd9, Tdrd1 and Mael showed the greatest decrease in the ovarian tissue, but the plasma E₂ levels showed the strongest increases (p<0.05). However, we found that the Mitopld, Miwi and Mili gene levels were decreased significantly after treatment with 12.5 I.U. PMSG/hCG. Our results suggested that exogenous gonadotropin administration leads to a significant decrease in the expression of the Mili, Miwi, Mael, Tdrd1, Tdrd9 and Mitopld genes, which are critically important in the piRNA pathway, and the changes in the expression levels of Tdrd9, Tdrd1 and Mael may be associated with plasma E₂ levels. New comprehensive studies are needed to reduce the potential effects of OS on the piRNA pathway, which silences transposable elements and maintains genome integrity, and to contribute to the safety of OS.

Oncologic oocyte cryopreservation: national comparison of fertility preservation between women with and without cancer

PURPOSE

The majority of data regarding oocyte cryopreservation (OC) outcomes focuses on healthy women. We compare trends, cycle characteristics, and outcomes between women freezing oocytes for fertility preservation due to cancer versus elective and other medical or fertility-related diagnoses.

METHODS

Retrospective cohort using national surveillance data includes all autologous OC cycles between 2012 and 2016. Cycles were divided into 4 distinct groups: cancer, elective, infertility, and medically indicated. We calculated trends and compared cycle and outcome characteristics between the 4 groups. We used multivariable log-binomial models to estimate associations between indication and gonadotropin dose, hyperstimulation, and cancelation and used Poisson regression models to estimate associations between indication and oocyte yield and maturity.

RESULTS

The study included 29,631 autologous OC cycles. Annual total (2925 to 8828) and cancer-related (177 to 504) cycles increased over the study period; the proportions remained constant. Compared to elective, cancer-related cycles were more likely to be performed among women < 35 years old, with higher BMI, living in the South, using an antagonist protocol. Compared to elective OC cycles, gonadotropin dose (aRR 0.89, 95%CI 0.80-0.99), cancelation (aRR 0.90, 95%CI 0.70-1.14), and hyperstimulation (aRR 1.46, 95%CI 0.77-2.29) were not different for cancer-related cycles. Oocyte yield and percent maturity were comparable in both groups.

CONCLUSION

The number of OC cycles among women with cancer has increased; however, the percentage OC cycles for cancer have remained stable. While patient demographic characteristics were different among those undergoing OC for cancer indication, cycle outcomes were comparable to elective OC. The outcomes of the subsequent oocyte thaw, fertilization, and embryo transfer cycles remain unknown.

Aromatase Inhibitors for Ovarian Stimulation in Patients with Breast Cancer

BACKGROUND

Breast cancer is the most common malignancy diagnosed in women, and its treatment has a high probability of loss of fertility. Oocyte vitrification is the most commonly used technique to preserve fertility before starting oncological treatment. Aromatase inhibitors induce hypoestrogenemia while promoting the release of gonadotropins and constitute an alternative drug for ovarian stimulation in patients with breast cancer.

OBJECTIVE

In this mini-review, we update and describe the current status of aromatase inhibitor use in controlled ovarian stimulation for oocyte vitrification in patients with breast cancer.

RESULTS

Aromatase inhibitors are commonly used in combination with gonadotropins for ovarian stimulation in patients with breast cancer who preserve their fertility through oocyte vitrification. They achieve similar ovarian responses as conventional ovarian stimulation protocols in regards to the number of oocytes, and no additional complications after their use have been reported. Furthermore, aromatase inhibitors seem to be safe not only for offspring, as no more congenital defects occur in newborns from pregnancies achieved after their use, but also for the patients, as no more malignancy recurrence or increased mortality was found in cohort studies.

CONCLUSION

Aromatase inhibitors are elective drugs for ovarian stimulation in patients with breast cancer who decide to preserve their fertility through oocyte vitrification.

[Oncofertility and breast cancer]

Over the past decades, progresses in oncology have improved the recovery rates after numerous malignant diseases, including breast cancer, that strike young adults in childbearing age. Quality of life of young cancer survivors has become a major issue. However, anticancer therapies can have a detrimental impact on fertility. It is now well-established that all patients should receive information about the fertility risks associated with their cancer treatment and the fertility preservation options available. These techniques aim to limit the negative impact of chemotherapy on the ovaries or to preserve gametes before treatment. Currently, oocyte or embryo freezing after controlled ovarian hyperstimulation represents the most effective method for preserving female fertility. Over the past years innovative protocols of ovarian stimulation have been developed to enable breast cancer patients to undergo oocyte or embryo cryopreservation irrespective of the phase of the cycle or without exogenous follicle-stimulating hormone related increase in serum estradiol levels. When controlled ovarian hyperstimualtion cannot be implemented, other techniques such as cryopreservation of ovarian cortex, in vitro maturation or the use of GnRH agonists may be proposed. However, it is important to inform patients that all these fertility preservation techniques do not represent a guarantee of pregnancy.

Impact of letrozole supplementation during ovarian stimulation for fertility preservation in breast cancer patients

Objectives

Oocyte and/or embryo vitrification after controlled ovarian stimulation (COS) represents the most established method of fertility preservation (FP) before cancer treatment. However, traditional COS regimens are associated with supraphysiologic serum estradiol and are therefore not recommended in estrogen-sensitive diseases such as breast cancer (BC). To protect the patients from the potential deleterious effects of elevated estrogen levels during COS for FP, protocols using aromatase inhibitors (letrozole) were developed. The present study aims at investigating whether COS with letrozole supplementation (COSTLES) modifies ovarian response in BC patients.

Study design

One hundred and seventy-seven BC patients candidates for FP using oocyte and/or embryo vitrification following COS referred to our center between July 2013 and December 2016 were included in this retrospective case-control study. 94 patients underwent COSTLES while 83 had standard GnRH antagonist protocol. The number of oocytes retrieved, oocyte maturation rates, number of oocytes vitrified and follicle responsiveness to FSH assessed by the Follicular Output Rate (FORT) were assessed.

Results

Women in both groups were comparable in terms of age and ovarian reserve tests leading to a similar number of oocyte recovered (13.1 ± 10.0 vs. 12.2 ± 8.0 oocytes, respectively, NS). However, oocyte maturation rates were significantly lower in COSTLES compared to standard protocol (64.9 ± 22.8 vs. 77.4 ± 19.3%, p < 0.001). As a result, the number of mature oocyte vitrified was lower in COSTLES group (7.8 ± 5.3 vs. 10.3 ± 8.5 oocytes, p < 0.001 respectively)

Conclusion

Despite similar response to exogenous FSH, BC patients having undergone COSTLES show reduced oocyte maturation rates in comparison with those having received standard stimulation regimen.

Effect of letrozole added to gonadotropins in controlled ovarian stimulation protocols on the yield and maturity of retrieved oocytes

We aimed to evaluate the effect of co-administration of letrozole and gonadotropins during ovarian stimulation on oocyte yield and maturation in breast cancer patients prior to chemotherapy. A retrospective cohort design was used comparing oocyte cryopreservation cycles among patients with breast cancer patients with other oncological indications and women undergoing elective oocyte cryopreservation. All patients were treated with GnRH antagonist protocol using GnRH agonist for final oocyte maturation. The breast cancer group was additionally treated with letrozole (5 mg/d) from the first day of treatment until the day of oocyte retrieval. The cohort included 418 patients: 145 breast cancer patients, 168 with other oncological indications, and 105 patients who chose to undergo elective oocyte cryopreservation. There were no significant differences among the groups in the number of retrieved oocytes or proportion of mature oocytes. On multivariate linear regression models, co-treatment with letrozole was not a significant factor for the number of retrieved oocytes or for oocyte maturation rate after controlling for age, body mass index (BMI), and FSH dose. We conclude that the addition of letrozole to gonadotropins does not increase the number of oocytes retrieved or the oocyte maturation rate.

Fertility preservation with random-start controlled ovarian stimulation and embryo cryopreservation for early pregnancy-associated breast cancer

We report a case of fertility preservation using random-start controlled ovarian stimulation (COS), intracytoplasmic sperm injection (ICSI) and embryo cryopreservation in a patient with early pregnancy-associated breast cancer. A 34-year-old nulliparous woman at 5 weeks of gestation was diagnosed with estrogen receptor (ER) positive, progesterone receptor (PR) positive and human epidermal growth factor receptor-2 (HER-2) negative infiltrating intraductal carcinoma. Urgent neoadjuvant chemotherapy was deemed necessary and the patient decided to terminate the pregnancy. Random-start COS was initiated 5 days after pregnancy termination using a letrozole-based protocol. The beta human chorionic gonadotropin level on the day of COS start was 119.8 mIU/mL. Twenty-nine oocytes were retrieved after 11 days of COS. Seventeen oocytes underwent successful fertilization and 10 blastocysts were cryopreserved. The patient subsequently initiated neoadjuvant chemotherapy with her oncologist. The current case highlights the feasibility of random-start COS and embryo cryopreservation for fertility preservation immediately after the termination of an early pregnancy in a patient with pregnancy-associated breast cancer.

Letrozole-associated controlled ovarian hyperstimulation in breast cancer patients versus conventional controlled ovarian hyperstimulation in infertile patients: assessment of oocyte quality related biomarkers

BACKGROUND

Fertility preservation (FP) protocols in case of breast cancer (BC) include mature oocyte cryopreservation following letrozole associated controlled ovarian hyperstimulation (Let-COH). To date, the impact of Let-COH on the follicular microenvironment has been poorly investigated, although a high androgen/estrogen ratio was previously associated with low oocyte quality.

METHODS

In this prospective study, follicular fluid (FF) steroid levels (estradiol, testosterone, progesterone) and cumulus cell (CC) gene expression related to oocyte quality (HAS2, PTGS2, GREM1) were compared between 23 BC patients undergoing Let-COH for FP and 24 infertile patients undergoing conventional COH without letrozole. All patients underwent an antagonist COH cycle, and ovulation was triggered with hCG or GnRHa in both groups.

RESULTS

FF estradiol levels were significantly lower while testosterone levels were significantly higher in the study group compared to controls irrespective of the trigger method. However, estradiol levels increased significantly with GnRHa triggering compared to hCG in the study group (median = 194.5 (95.4-438) vs 64.4 (43.8-152.4) ng/ml, respectively, p < 0.001), but not in the control group (median = 335.5 (177.5-466.7) vs 354 (179-511) ng/ml, respectively). After hCG trigger, Cumulus cell (CC) gene expression was lower in the study group compared to the control group, and difference was significant for PTGS2. Conversely, CC gene expression of PTGS2 and GREM1 was significantly higher in the study group compared to controls when ovulation was triggered with GnRHa.

CONCLUSIONS

Let-COH triggered with hCG may negatively impact oocyte quality. However, ovulation triggering with GnRHa may improve the oocyte microenvironment and cumulus cell genes expression in Let-COH, suggesting a positive impact on oocyte quality in breast cancer patients.

TRIAL REGISTRATION

Clinicaltrials.gov - NCT02661932 , registered 25 January 2016, retrospectively registered.

Specific protocols of controlled ovarian stimulation for oocyte cryopreservation in breast cancer patients

Background

Fertility preservation is an important concern in breast cancer patients. In the present investigation, we set out to create a specific protocol of controlled ovarian stimulation (cos) for oocyte cryopreservation in breast cancer patients.

Methods

From November 2014 to December 2016, 109 patients were studied. The patients were assigned to a specific random-start ovarian stimulation protocol for oocyte cryopreservation. The endpoints were the numbers of oocytes retrieved and of mature oocytes cryopreserved, the total number of days of ovarian stimulation, the total dose of gonadotropin administered, and the estradiol level on the day of the trigger.

Results

Mean age in this cohort was 31.27 ± 4.23 years. The average duration of cos was 10.0 ± 1.39 days. The mean number of oocytes collected was 11.62 ± 7.96 and the mean number of vitrified oocytes was 9.60 ± 6.87. The mean estradiol concentration on triggering day was 706.30 ± 450.48 pg/mL, and the mean dose of gonadotropins administered was 2610.00 ± 716.51 IU. When comparing outcomes by phase of the cycle in which cos was commenced, we observed no significant differences in the numbers of oocytes collected and vitrified, the length of ovarian stimulation, and the estradiol level on trigger day. The total dose of follicle-stimulating hormone and human menopausal gonadotropin administered was statistically greater in the group starting cos in the luteal phase than in the group starting in the late follicular phase.

Conclusions

Our results suggest that using a specific protocol with random-start ovarian stimulation for oocyte cryopreservation in breast cancer patients is effective and could be offered to young women undergoing oncologic treatment.

Fertility preserving options for gynecologic malignancies: A review of current understanding and future directions

Gynecological malignancies affect significant proportion of women in whom fertility preservation is a priority. Advancing reproductive technology and modern surgical techniques are changing the way young women with cancer are counseled regarding their fertility plans at time of cancer diagnosis. This review article provides the reader with fertility preserving updates in gynecologic malignancies as well as those with genetic predisposition for gynecologic malignancies. The different types of gynecologic malignancies including cervical, endometrial, and ovarian cancers and their unique obstacles are addressed separately. New insights into conservative cervical cancer surgery and fertility preserving neoadjuvant chemotherapy followed by fertility preserving surgery for cervical cancer are discussed. Hormonal management of endometrial cancer are highlighted. Additionally, better understanding of ovarian failure with modern chemotherapy/radiation therapy is summarized. Finally, modern reproductive techniques such as ovarian cryopreservation are reviewed as well as those in early stages are development such as artificial ovarian tissue are previewed.

Motherhood after breast cancer: can we balance fertility preservation and cancer treatment? A narrative review of the literature

Breast cancer may affect young women who have not yet completed childbearing. Assisted reproductive technology (ART) provides alternatives for fertility preservation such as oocyte, embryo or ovarian tissue cryopreservation. We reviewed the published literature on fertility-preserving management in breast cancer, aiming at finding evidence to answer the following questions: (1) What are the fertility sparing options available?; (2) How do these women respond to IVF? and (3) Can pregnancy influence breast cancer recurrence? There is a paucity of publications describing clinical experience and outcome data which limits accessibility to fertility preservation in this setting. Presently, oocyte or embryo cryopreservation are the main options for fertility preservation. IVF success rates are comparable to the ones of non-oncological populations according to the woman's age but current published studies lack data on definitive success rates following embryo banking for cancer patients. The perception that IVF and pregnancy may worsen cancer prognosis remains, despite the lack of scientific evidence to support this notion. Published studies show reassuring results for pregnancies occurring >2 years after breast cancer diagnosis. The best published evidence suggests pregnancy after breast cancer does not increase the risk of disease recurrence, thus pregnancy should not be forbidden once treatment is completed. Decision making for women diagnosed with cancer requires up-to-date knowledge of the efficacy and safety of available options. Providing consultation with a reproductive specialist and appropriate information on fertility preservation for these women should be an essential aspect of their supportive care.

The VEGF and PEDF levels in the follicular fluid of patients co- treated with LETROZOLE and gonadotropins during the stimulation cycle

BACKGROUND

Previous studies have shown that androgens, in addition to serving as precursors for ovarian estrogen synthesis, also have a fundamental role in primate ovarian follicular development by augmentation of FSH receptor expression on granulosa cells. Recent studies have shown that aromatase inhibitor, letrozole, improves ovarian response to FSH in normal and poor responder patients, possibly by increasing intraovarian androgen levels. Studies in mice also showed an effect of letrozole to increase pigment epithelium-derived factor (PEDF) and to lower vascular epithelial growth factor (VEGF), which might be expected to reduce the risk of ovarian hyperstimulation syndrome (OHSS) with stimulation. The aim of this study was to compare the VEGF and PEDF levels in the follicular fluids of normal responders treated with letrozole and gonadotropins during the ovarian stimulation with patients treated with gonadotropins only.

METHODS

A single center, prospective clinical trial. We collected follicular fluid from 26 patients, on a GnRH antagonist protocol, dual triggered with hCG and GnRH agonist. The patients in one group were co-treated with letrozole and gonadotropins during the ovarian stimulation and the patients in the other group were treated with gonadotropins only. VEGF, PEDF, estrogen, progesterone and testosterone levels were measured by ELISA kits.

RESULTS

The age of the patients, the total dose of gonadotropins and the number of oocytes were comparable between the two groups. In the follicular fluid, the estrogen levels (2209 nmol/l vs. 3280 nmol/l, p = 0.02) were significantly decreased, and the testosterone levels (246.5 nmol/l vs. 40.7 nmol/l, p < 0.001) were significantly increased in the letrozole group compared to the gonadotropin only group. The progesterone levels (21.4 μmol/l vs. 17.5 p = NS) were comparable between the two groups. The VEGF levels (2992 pg/ml vs. 1812 pg/ml p = 0.02) were significantly increased and the PEDF levels (9.7 ng/ml vs 17.3 ng/ml p < 0.001) were significantly decreased in the letrozole group.

CONCLUSIONS

Opposite to observations in the mouse, we found that VEGF levels were increased and PEDF levels were decreased in the follicular fluid in patients treated with letrozole during the stimulation cycles. Further investigation is required to determine if patients treated with letrozole during the IVF stimulation protocol are at increased risk for developing OHSS as a result of these findings.

Thirteen years' experience in fertility preservation for cancer patients after in vitro fertilization and in vitro maturation treatments

PURPOSE

This study aims to describe the experience and outcomes of in vitro maturation without ovarian stimulation (IVM-FP) and conventional in vitro fertilization after ovarian stimulation (IVF-FP) in a fertility preservation (FP) program for women with cancer.

METHODS

Retrospective cohort study from 2003 to 2015 was conducted. The study population consisted of 353 women with cancer who underwent 394 FP cycles (187 IVF-FP cycles and 207 IVM-FP) for oocytes and/or embryos cryopreservation.

RESULT(S)

Comparatively with IVM-FP, IVF-FP had a higher median [25th-75th percentile] number of oocytes collected-12 [8-18] vs 7 [5-13]; oocytes cryopreserved-10 [6-15] vs 5 [2-8]; and, where applicable, embryos cryopreserved-5 [3-7] vs 3 [2-5] (p < 0.000001). Following FP treatment, 32 patients (9.0%) died, 18 patients (5.6%) conceived spontaneously, and 23 patients (6.5%) returned to attempt pregnancy with a median lapse of returning of 4.6 [3.1-6.1] years. Of these, cryopreserved oocytes or embryos were used in 33 cycles (19 after IVF-FP and 14 after IVM-FP). Overall, the cumulative pregnancy rate (CPR) was 47.6% (10/21) and the live birth rate (LBR) was 38.1% (8/21). Per cycle, CPR and LBR were 37 and 31% following IVF-FP and 14 and 7% following IVM-FP, although these differences did not reach statistical significance. We report the fourth live birth after IVM-FP in cancer, and the first one after IVM embryo warming resulting from in vivo oocyte retrieval and IVM procedure.

CONCLUSION(S)

Both IVF-FP and IVM-FP are possible options for FP women with cancer. Due to minimal data regarding ultimate outcomes, further follow-up is needed.

A specific controlled ovarian stimulation (COS) protocol for fertility preservation in women with breast cancer undergoing neoadjuvant chemotherapy

Aim of the study

The authors present a novel and specific controlled ovarian stimulation protocol for fertility preservation in women with estrogen-positive receptor breast cancer undergoing neoadjuvant chemotherapy. The protocol foresees random start ovarian stimulation and the use of letrozole associated to tamoxifen.

Material and methods

Forty breast cancer patients were included in the study. COS was performed either with recombinant FSH or hMG. Concomitantly with COS, letrozole in a dose of 5 mg and tamoxifen in a dose of 20 mg were given orally on a daily basis. The trigger was performed with 0.2 mg of triptorelin, in the presence of follicles ≥ 19 mm. Oocyte retrieval was scheduled 35-36 hours after triptorelin injection. Our main outcome measures were the number of oocytes collected and number of oocytes vitrified, the length of ovarian stimulation, total dose of gonadotropins administered, and levels of estradiol on the day of the trigger.

Results

The mean age of patients was 30.43 ±4.25 years. Nineteen women commenced COS in the luteal phase, eleven in the early follicular phase and ten in the late follicular phase. The mean number of collected oocytes was 11.78 ±9.12 and the mean number of vitrified oocytes was 9.72 ±7.36. The mean duration of COS was 10.03 ±1.33 days. The mean estradiol concentrations on the triggering day was 623.10 ±441.27, and the mean dose of gonadotropins administered was 2540 ±713.10.

Conclusions

The authors suggest that the protocol is efficient and may be a safe option for oocyte vitrification in these patients.

In vitro fertilization treatments with the use of clomiphene citrate or letrozole

There has been increasing interest in combining the oral agents clomiphene citrate (CC) and letrozole with gonadotropins in IVF: for poor responders to reduce the amount of gonadotropins used, and in normal responders to reduce the incidence of ovarian hyperstimulation (OHSS). In normal responders, mild stimulation with the use of CC and gonadotropins was found to decrease the number of oocytes retrieved and result in good pregnancy rates, but in most studies the cumulative pregnancy rate was lower compared with conventional ovarian stimulation when frozen embryo transfers were considered. Coadministration of letrozole and gonadotropins has mainly been used in patients with breast cancer to prevent the massive elevation of serum E₂ concentrations with the use of standard controlled ovarian hyperstimulation. CC and letrozole have both been used with gonadotropins in poor responders and have been shown to reduce the amount of gonadotropin used without reducing the pregnancy rate. Letrozole use with gonadotropins in IVF cycles may increase endometrial receptivity by increasing integrin expression in the endometrium and by lowering estrogen concentrations to more physiologic levels.

Recent advances in in vitro fertilization

The field of assisted reproductive technology is rapidly progressing with many new advances in the last decade. The present review discusses methods to improve oocyte quality in older women and new stimulation protocols that may improve the number of mature oocytes retrieved during an in vitro fertilization cycle. We will discuss the present use of pre-implantation genetic screening (PGS) and finally focus on some new methods to determine endometrial receptivity. The focus of this review is to point out areas of technology that may be controversial or are new enough to require proper controlled studies for validation.

Does daily co-administration of letrozole and gonadotropins during ovarian stimulation improve IVF outcome?

BACKGROUND

For the last year we have been treating normal responders with gonadotropins and letrozole during the whole stimulation in order to improve response to FSH by increasing the intrafollicular androgen concentration, and to reduce circulating estrogen concentrations. The aim of this study was to compare the IVF outcome of normal responders treated with letrozole and gonadotropins during ovarian stimulation with patients treated with gonadotropins only.

METHODS

A single centre retrospective cohort study of 174 patients (87 in each group).

RESULTS

The age of the patients was comparable between the groups. Estradiol levels were significantly higher in the control group (6760 pmol/L vs. 2420 pmol/L respectively, p < 0.01), and the number of follicles ≥15 mm at the trigger day was significantly lower in the control group (7.9 vs. 10, p = 0.02). The number of retrieved oocytes (10 vs. 14.5, p < 0.01), MII oocytes (7.9 vs. 11.2, p < 0.01) and blastocysts (2.7 vs. 4.0, p = 0.02) was significantly higher in the study group. We found no significant differences in the cumulative pregnancy outcome between the two groups (65.2% vs 58.3% p = NS).

CONCLUSIONS

We conclude that co-treatment with letrozole improves the IVF outcome in normal responders in terms of increased number of blastocysts obtained without increasing the pregnancy rate or the risk of OHSS.

Fertility Preservation and Sexual Health After Cancer Therapy

Recent developments in cancer diagnostics and treatments have considerably improved long-term survival rates. Despite improvements in chemotherapy regimens, more focused radiotherapy and diverse surgical options, cancer treatments often have gonadotoxic side-effects that can manifest as loss of fertility or sexual dysfunction, particularly in young cancer survivors. In this review, we focus on two pertinent quality-of-life issues in female cancer survivors of reproductive age-fertility preservation and sexual function. Fertility preservation encompasses all clinical and laboratory efforts to preserve a woman's chance to achieve future genetic motherhood. These efforts range from well-established protocols such as ovarian stimulation with cryopreservation of embryos or oocytes, to nascent clinical trials involving cryopreservation and re-implantation of ovarian tissue. Therefore, fertility preservation strategies are individualized to the cancer diagnosis, time interval until initiation of treatments must begin, prognosis, pubertal status, and maturity level of patient. Some patients choose not to pursue fertility preservation, and the conversation then centers around other quality of life issues. Not all cancer treatments cause loss of fertility; however, most treatments can directly impact the physical and psychosocial aspects of sexual function. Cancer treatment is also associated with fear, anxiety, and depression, which can further decrease sexual desire, function, and frequency. Sexual dysfunction after cancer treatment is generally ascertained by compassionate inquiry. Strategies to promote sexual function after cancer treatment include pelvic floor exercises, clitoral therapy devices, pharmacologic agents, as well as couples-based psychotherapeutic and psycho-educational interventions. Quality-of-life issues in young cancer survivors are often best addressed by utilizing a multidisciplinary team consisting of physicians, nurses, social workers, psychiatrists, sex educators, counselors, or therapists.

Random-start ovarian stimulation in women desiring elective cryopreservation of oocytes

The current study investigates the utility of random-start ovarian stimulation in women desiring elective oocyte cryopreservation. Women in the study cohort underwent random-start ovarian stimulation, and were subdivided based on the phase of the menstrual cycle that ovarian stimulation began, i.e. early follicular, late follicular or luteal phase. Women undergoing conventional cycle day (CD) 2/3 ovarian stimulation start were controls. A total of 1302 women were included - 859 (66.0%) conventional CD 2/3, 342 (26.3%) early follicular, 42 (3.2%) late follicular and 59 (4.5%) luteal ovarian stimulation starts. There was no difference in the demographics or baseline ovarian stimulation characteristics. The duration of ovarian stimulation (11 versus 9 days; P < 0.001) and total dosage of gonadotrophins administered (4095.5 versus 3155 IU; P < 0.001) was higher in the random-start group. The number of total and MII oocytes in the control and random-start groups was similar. A non-significant trend towards increased cycle cancellation was noted in the late follicular start group (7.1%). Study findings indicate the number of total and MII oocytes derived from random-start protocols initiated during any phase of the menstrual cycle is similar to conventional CD 2/3 ovarian stimulation start protocols in women desiring elective oocyte cryopreservation.