The Australian New Zealand Consortium in Children, Adolescents, and Young Adults Oncofertility action plan.

International and national oncofertility networks, including the US-led Oncofertility Consortium, FertiProtekt, and the Danish Network, have played pivotal roles in advancing the discipline of oncofertility over the last decade. Many other countries lack a shared approach to pediatric oncofertility health service delivery. This study aims to describe baseline oncofertility practices at Australian New Zealand Children's Haematology/Oncology Group centers in 2019-2021, describe binational priorities for care, and propose a 5-year action plan for best practice to be implemented by the newly formed Australian New Zealand Consortium in Children, Adolescents, and Young Adults (CAYA) Oncofertility (ANZCO).

School-age outcomes among IVF-conceived children: A population-wide cohort study.

BACKGROUND: In vitro fertilisation (IVF) is a common mode of conception. Understanding the long-term implications for these children is important. The aim of this study was to determine the causal effect of IVF conception on primary school-age childhood developmental and educational outcomes, compared with outcomes following spontaneous conception. METHODS AND FINDINGS: Causal inference methods were used to analyse observational data in a way that emulates a target randomised clinical trial. The study cohort comprised statewide linked maternal and childhood administrative data. Participants included singleton infants conceived spontaneously or via IVF, born in Victoria, Australia between 2005 and 2014 and who had school-age developmental and educational outcomes assessed. The exposure examined was conception via IVF, with spontaneous conception the control condition. Two outcome measures were assessed. The first, childhood developmental vulnerability at school entry (age 4 to 6), was assessed using the Australian Early Developmental Census (AEDC) (n = 173,200) and defined as scoring <10th percentile in ≥2/5 developmental domains (physical health and wellbeing, social competence, emotional maturity, language and cognitive skills, communication skills, and general knowledge). The second, educational outcome at age 7 to 9, was assessed using National Assessment Program-Literacy and Numeracy (NAPLAN) data (n = 342,311) and defined by overall z-score across 5 domains (grammar and punctuation, reading, writing, spelling, and numeracy). Inverse probability weighting with regression adjustment was used to estimate population average causal effects. The study included 412,713 children across the 2 outcome cohorts. Linked records were available for 4,697 IVF-conceived cases and 168,503 controls for AEDC, and 8,976 cases and 333,335 controls for NAPLAN. There was no causal effect of IVF-conception on the risk of developmental vulnerability at school-entry compared with spontaneously conceived children (AEDC metrics), with an adjusted risk difference of -0.3% (95% CI -3.7% to 3.1%) and an adjusted risk ratio of 0.97 (95% CI 0.77 to 1.25). At age 7 to 9 years, there was no causal effect of IVF-conception on the NAPLAN overall z-score, with an adjusted mean difference of 0.030 (95% CI -0.018 to 0.077) between IVF- and spontaneously conceived children. The models were adjusted for sex at birth, age at assessment, language background other than English, socioeconomic status, maternal age, parity, and education. Study limitations included the use of observational data, the potential for unmeasured confounding, the presence of missing data, and the necessary restriction of the cohort to children attending school. CONCLUSIONS: In this analysis, under the given causal assumptions, the school-age developmental and educational outcomes for children conceived by IVF are equivalent to those of spontaneously conceived children. These findings provide important reassurance for current and prospective parents and for clinicians.

Fertility assessment and treatment in adolescent and young adult cancer survivors.

In the survivorship setting, adolescent and young adult (AYA) cancer survivors frequently demonstrate little knowledge of infertility risk, are unclear regarding their fertility status, and may under- or overestimate their treatment-related risk for infertility. In female AYA survivors, ovarian function usually parallels fertility, and can be assessed with serum hormone levels and ultrasonography. Posttreatment fertility preservation may be appropriate for survivors at risk for primary ovarian insufficiency. In male AYA survivors, fertility and gonadal function are not always equally affected, and can be assessed with a semen analysis and serum hormones, respectively. As reproductive health issues are commonly cited as an important concern by survivors of AYA cancer, multidisciplinary care teams including oncology, endocrinology, psychology, and reproductive medicine are advocated, with the aim of optimal provision of fertility advice and care for AYA cancer survivors.

Timing of progesterone luteal support in natural cryopreserved embryo transfer cycles: back to basics.

Moderate quality evidence suggests that the administration of progesterone luteal phase support (LPS) is beneficial in natural and modified (HCG-triggered) natural frozen embryo transfer (FET) cycles. No comparative studies examining the optimal timing of progesterone LPS administration in natural FET cycles have been conducted, and the common practice differs greatly between clinics worldwide. In the absence of clinical trials, we aimed to provide a scheme for progesterone supplementation in an attempt to mimic its natural secretion by the corpus luteum. On the basis of early studies of ovulation physiology, we suggest that progesterone luteal support administration in natural FET cycles should start 36 h after the onset of the LH surge when measured in a morning serum test, or 36 h after the administration of HCG for triggering final follicular maturation. Blastocyst transfer should be carried out after 5 full days of progesterone supplementation. Randomized clinical trials are required to confirm these recommendations.

Post-warming embryo morphology is associated with live birth: a cohort study of single vitrified-warmed blastocyst transfer cycles.

PURPOSE: This study aims to examine whether blastocyst morphology post-warming correlates with live birth. METHODS: In this cohort study, morphological characteristics post-warming were reviewed in all single vitrified-warmed blastocyst transfer cycles performed between November 2016 and May 2017. Immediately before transfer, the degree of blastocoel re-expansion was graded as A, fully expanded; B, partially expanded ≥ 50%; C, partially expanded < 50%; and D, collapsed. The degree of post-warming cell survival was graded on a scale of 50 to 100% and was then classified into 4 groups: very low 50-70%, low 71-80%, moderate 81-90%, and high 91-100%. RESULTS: Overall, 612 cycles were reviewed, of which 196 included PGT-A tested embryos. The live birth rate (LBR) increased from 11.4% in the collapsed blastocysts group to 38.9% in the post-warming full re-expansion group (p < 0.001) and from 6.5% for blastocysts with a very low cell survival rate to 34.7% for blastocysts with high cell survival rate (p = 0.001). LBR was 6.7% for blastocysts with the worst post-warming morphological characteristics, namely, collapsed with very low cell survival rate. On multivariate analyses, partial blastocyst re-expansion ≥ 50%, full re-expansion, and high cell survival rate remained significantly associated with live birth, after controlling for female age, pre-vitrification morphological grading, and PGT-A. A sub-analysis of cycles using PGT-A tested embryos showed similar results. CONCLUSION: Post-warming re-expansion and high cell survival rate are associated with higher LBR in euploid and untested blastocysts. However, embryos with poor post-warming morphology still demonstrate a considerable probability of live birth, and they should not be discarded.

A survey study of endometrial receptivity tests and immunological treatments in in vitro fertilisation (IVF).

BACKGROUND: Suboptimal endometrial receptivity is a key factor behind in vitro fertilisation (IVF) implantation failure. Direct clinical tests of the endometrium of natural killer (NK) cells and endometrial receptivity analysis (ERA) are controversial. AIMS: To examine the current practice of endometrial receptivity tests (NK cells and ERA) and immunological treatments (corticosteroids, anticoagulants, antiplatelets, intravenous immunoglobulin, Intralipid, other) among fertility specialists in Australia and New Zealand. METHODS: A prospective 23-item web-based survey was distributed by email via the Fertility Society of Australia and New Zealand, between August and October 2020. Data were collected and analysed using Qualtrics. RESULTS: Of 238 fertility specialists, 90 completed the survey (response rate 37.8%). ERA (48/90, 53.3%) was most commonly ordered, followed by uterine NK (uNK) (36/90, 40.0%) and peripheral blood NK (pNK) (12/90, 13.3%). For all tests, the most common indication was recurrent implantation failure (RIF) (41/48, 22/36, 6/12; 85.4%, 61.1%, and 50.0%, respectively for ERA, uNK and pNK). Of those that did not offer these tests, the main reason cited was insufficient evidence (30/42, 47/54, 68/78; 71.4%, 87.0%, and 87.0%). A third of specialists offered empirical immunological treatment for RIF (30/90, 33.3%): anticoagulants (28/30, 93.3%), antiplatelets (27/30, 90.0%), and corticosteroids (25/30; 83.3%). The majority of specialists (56/90, 62.2%) stated they had refused a patient request for endometrial testing or treatment. CONCLUSIONS: Tests for presumed endometrial receptivity pathology are often used in Australia and New Zealand. Immunological treatments for RIF are commonly employed empirically, without strong evidence of their effectiveness or safety. Further studies should focus on education and clinical adherence to evidence-based guidelines.

Fertility preservation for female patients with childhood, adolescent, and young adult cancer: recommendations from the PanCareLIFE Consortium and the International Late Effects of Childhood Cancer Guideline Harmonization Group.

Female patients with childhood, adolescent, and young adult cancer are at increased risk for fertility impairment when treatment adversely affects the function of reproductive organs. Patients and their families desire biological children but substantial variations in clinical practice guidelines reduce consistent and timely implementation of effective interventions for fertility preservation across institutions. As part of the PanCareLIFE Consortium, and in collaboration with the International Late Effects of Childhood Cancer Guideline Harmonization Group, we reviewed the current literature and developed a clinical practice guideline for fertility preservation in female patients who were diagnosed with childhood, adolescent, and young adult cancer at age 25 years or younger, including guidance on risk assessment and available methods for fertility preservation. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to grade the available evidence and to form the recommendations. This clinical practice guideline leverages existing evidence and international expertise to develop transparent recommendations that are easy to use to facilitate the care of female patients with childhood, adolescent, and young adult cancer who are at high risk for fertility impairment. A complete review of the existing evidence, including a quality assessment, transparent reporting of the guideline panel's decisions, and achievement of global interdisciplinary consensus, is an important result of this intensive collaboration.

An algorithm to personalise the diagnosis of recurrent implantation failure based on theoretical cumulative implantation rate.

Recurrent implantation failure (RIF) is an imprecisely defined disorder lacking a robust scientific basis. The incomplete understanding of RIF provides significant diagnostic and therapeutic challenges, and a better understanding of the underlying issues is necessary to improve outcomes. We propose a novel concept termed 'Theoretical Cumulative Implantation Rate', the calculation of which is based on objective data, to define whether a patient should be diagnosed with RIF. An updated definition to assist with patient counselling and planning research studies, which is more precise and standardised, is well overdue.

Ovarian tissue grafting: Lessons learnt from our experience with 55 grafts.

Purpose: Uncertainties remain regarding the clinical efficacy of ovarian tissue cryopreservation and grafting. We report a retrospective analysis of reproductive outcomes and lessons learnt following 55 ovarian tissue transplant procedures at our center from 2006 to 2019. Methods: We analyzed variables related to graft success such as tissue volume, follicular density, total follicular volume, and age on the duration of graft function. Results: Follicular density and total follicular volume correlate positively with duration of graft function. All clinical pregnancies in our cohort occurred in women who were aged 35 or less at the time of ovarian tissue cryopreservation. Conclusion: Graft success, as determined by eventual pregnancy and the longevity of graft function, may be impacted by factors including age at cryopreservation, follicular density, and total follicular volume.

Satisfaction, disappointment and regret surrounding fertility preservation decisions in the paediatric and adolescent cancer population.

PURPOSE: With over 80% of paediatric and adolescent cancer patients surviving into adulthood, quality-of-life issues such as future fertility are increasingly important. However, little is known about regret around decisions to pursue or forgo fertility preservation (FP). We investigated the risk of decision regret in families involved in making a FP decision and explored contributive factors. METHODS: Parents and patients ≥ 15 years were invited to participate. Participants completed a 10-item survey, including a validated Decision Regret Scale. Scores ≥ 30 indicated high regret. Free-text response items allowed participants to provide reasons for satisfaction or regret. RESULTS: A total of 108 parents and 30 patients participated. Most (81.4%) reported low regret (mean score 13.7). On multivariate analysis, predictors of low regret included having a FP procedure and a fertility discussion pre-treatment. Most participants believed that FP offers hope for future fertility. Some reported dissatisfaction with the process of decision-making. CONCLUSION: Overall levels of regret in the study population were low, with factors associated with quality, timely discussion and belief in the success of FP technology being predictors of low regret. However, dissatisfaction with the decision-making process itself revealed that refinements to the programme are required to meet families' needs.

Preventing ovarian failure associated with chemotherapy.

Alkylating chemotherapy is often used to treat pre-menopausal women for various malignancies and autoimmune diseases. Chemotherapy-associated ovarian failure is a potential consequence of this treatment which can cause infertility, and increases the risk of other long term adverse health sequelae. Randomised trials, predominantly of women undergoing alkylating chemotherapy for breast cancer, have shown evidence for the efficacy of gonadotropin-releasing hormone agonists (GnRHa) in preventing chemotherapy-associated ovarian failure. The European St Gallen and United States National Comprehensive Cancer Network guidelines recommend the use of concurrent GnRHa to reduce the risk of ovarian failure for pre-menopausal women undergoing chemotherapy for breast cancer. The GnRHa goserelin, a monthly 3.6 mg depot subcutaneous injection, has recently been listed on the Australian Pharmaceutical Benefits Scheme to reduce risk of ovarian failure for pre-menopausal women receiving alkylating therapies for malignancy or autoimmune disease. The first dose of goserelin should ideally be administered at least 1 week before commencement of alkylating treatment and continued 4-weekly during chemotherapy. Concurrent goserelin use should now be considered for all pre-menopausal women due to commence alkylating chemotherapy (except those with incurable cancer), regardless of their childbearing status, in an effort to preserve their ovarian function. For women who have not completed childbearing, consideration of other fertility preservation options, such as cryopreservation of embryos or oocytes, is also important.

Cryopreservation of reproductive material before cancer treatment: a qualitative study of health care professionals' views about ways to enhance clinical care.

BACKGROUND: Cancer treatment can diminish fertility in women and men. The need for fertility preservation is growing as increasing numbers of people survive cancer. Cryostorage of reproductive material to preserve potential for conception for cancer survivors has moved from being experimental to being a part of clinical management of women and men who are diagnosed with cancer in their reproductive years. There is little existing evidence about how fertility preservation services can be enhanced to meet the complex needs of patients who are diagnosed with cancer in their reproductive years. The aim of this research was to inform clinical practice development by drawing on the collective experience and knowledge of staff at well-established clinics that offer fertility preservation before cancer treatment. METHODS: A qualitative research model was adopted using semi-structured interviews with professionals involved in the care of people who freeze reproductive material before cancer treatment. In the state of Victoria, Australia, two large assisted reproductive technology (ART) centres have been providing fertility preservation services for more than two decades. An invitation to participate in a semi-structured interview about clinical care in the context of fertility preservation was emailed to past and current staff members. To capture diverse perspectives, informants were sought from all relevant professions: fertility specialists, andrologists, nurses, embryologists/scientists, counsellors, and administrative staff. Transcripts were analysed thematically. RESULTS: Thirteen key informants were interviewed from August 2013 to February 2014. The identified themes relating to enhancing clinical care in a fertility preservation service were communication between oncology and ART specialists; managing urgency; managing patients' expectations; establishing and implementing protocols, systems, and data bases; and maintaining contact with patients. CONCLUSION: The collective knowledge of this study's informants, who represent multidisciplinary teams with more than two decades' experience in fertility preservation, yields important insights into strategies that fertility preservation services can employ to promote the integration of oncology and fertility care, the psychosocial care of patients, data recording and monitoring, and reporting of outcomes.

Anti-Müllerian hormone serum concentrations of women with germline BRCA1 or BRCA2 mutations.

STUDY QUESTION: Do women with ITALIC! BRCA1 or ITALIC! BRCA2 mutations have reduced ovarian reserve, as measured by circulating anti-Müllerian hormone (AMH) concentration? SUMMARY ANSWER: Women with a germline mutation in ITALIC! BRCA1 have reduced ovarian reserve as measured by AMH. WHAT IS KNOWN ALREADY: The DNA repair enzymes encoded by ITALIC! BRCA1 and ITALIC! BRCA2 are implicated in reproductive aging. Circulating AMH is a biomarker of ovarian reserve and hence reproductive lifespan. STUDY DESIGN, SIZE, DURATION: This was a cross-sectional study of AMH concentrations of 693 women at the time of enrolment into the Kathleen Cuningham Foundation Consortium for research in the Familial Breast Cancer (kConFab) cohort study (recruitment from 19 August 1997 until 18 September 2012). AMH was measured on stored plasma samples between November 2014 and January 2015 using an electrochemiluminescence immunoassay platform. PARTICIPANTS/MATERIALS, SETTING, METHODS: Eligible women were from families segregating ITALIC! BRCA1 or ITALIC! BRCA2 mutations and had known mutation status. Participants were aged 25-45 years, had no personal history of cancer, retained both ovaries and were not pregnant or breastfeeding at the time of plasma storage. Circulating AMH was measured for 172 carriers and 216 non-carriers from families carrying ITALIC! BRCA1 mutations, and 147 carriers and 158 non-carriers from families carrying ITALIC! BRCA2 mutations. Associations between plasma AMH concentration and carrier status were tested by linear regression, adjusted for age at plasma storage, oral contraceptive use, body mass index and cigarette smoking. MAIN RESULTS AND THE ROLE OF CHANCE: Mean AMH concentration was negatively associated with age ( ITALIC! P < 0.001). Mutation carriers were younger at blood draw than non-carriers ( ITALIC! P ≤ 0.031). ITALIC! BRCA1 mutation carriers had, on average, 25% (95% CI: 5%-41%, ITALIC! P = 0.02) lower AMH concentrations than non-carriers and were more likely to have AMH concentrations in the lowest quartile for age (OR 1.84, 95% CI: 1.11-303, ITALIC! P = 0.02). There was no evidence of an association between AMH concentration and ITALIC! BRCA2 mutation status ( ITALIC! P = 0.94). LIMITATIONS, REASONS FOR CAUTION: AMH does not directly measure the primordial follicle pool. The clinical implications of the lower AMH concentrations seen in ITALIC! BRCA1 mutation carriers cannot be assessed by this study design. WIDER IMPLICATIONS OF THE FINDINGS: Women with a germline mutation in ITALIC! BRCA1 may have reduced ovarian reserve. This is consistent with other smaller studies in the literature and has potential implications for fertility and reproductive lifespan. STUDY FUNDING/COMPETING INTERESTS: kConFab is supported by a grant from the Australian National Breast Cancer Foundation, and previously by the National Health and Medical Research Council (NHMRC), the Queensland Cancer Fund, the Cancer Councils of New South Wales, Victoria, Tasmania and South Australia, and the Cancer Foundation of Western Australia. K.A.P. is an Australian National Breast Cancer Foundation Practitioner Fellow. J.L.H. is a NHMRC Senior Principal Research Fellow. M.H. is a NHMRC Practitioner Fellow. R.A.A. reports personal fees from Roche Diagnostics & Beckman Coulter outside the submitted work and C.S. reports other earnings from Melbourne IVF outside the submitted work. The remaining authors have nothing to declare and no conflicts of interest.

Fertility in premenopausal women post autologous stem cell transplant with BEAM conditioning.

There is currently minimal data on fertility outcomes in premenopausal women undergoing autologous stem cell transplant (ASCT) with carmustine, etoposide, cytarabine and melphalan (BEAM) conditioning. A retrospective analysis of fertility outcomes in premenopausal females aged between 18 and 40 yr who underwent BEAM/ASCT for lymphoma between 1995 and 2011 was performed at four transplant centres. Of 41 premenopausal women who underwent BEAM conditioning, 25 met the inclusion criteria with the main exclusion criterion being inadequate documentation. Eighteen had Hodgkin lymphoma, and seven had non-Hodgkin lymphoma. Median number of chemotherapy regimens pretransplant was 2 (1-3). Seventeen women (68%) with a median age at transplant of 25 yr (range 17-33) recovered their menses. The comparative group without recovery was older with a median age of 34 yr (range 20-40) (P = 0.007). Ten patients, with a median age at transplant of 22 yr (range 17-30), had 15 naturally conceived pregnancies. Chemotherapy regimens and lymphoma type did not obviously influence the incidence of menses recovery or conception. The incidence of recovery of menses and fertility in premenopausal women undergoing BEAM/ASCT for lymphoma is substantial. Younger age at transplant correlates with superior fertility outcomes.

Live birth from ovarian grafted tissue after pelvic radiation for rectal cancer.

Objective: To study the management of a woman who returned to conceive after high-dose radiation treatment, with documentation of uterine dosimetry, and the efficacy of ovarian tissue grafted into an irradiated pelvis. Design: Case report. Setting: Private and public In Vitro Fertilization units. Patient: A 26-year-old woman underwent radiation treatment for rectal cancer, with half of the uterus and the fundus being exposed to radiation doses of 50 and 25 Gy, respectively. We report the details of the uterine assessment, determining suitability of conception with her own uterus, pregnancy surveillance, and reproductive outcome. Interventions: In Vitro Fertilization stimulation grafted ovarian tissue to assist with pregnancy. Main Outcome Measures: Successful conception and live birth, pregnancy complications and management of high risk pregnancy. Results: The results of magnetic resonance imaging and pelvic ultrasound showed a small uterus with preserved junctional zone anatomy, and although the endometrium was initially thin after high-dose estrogen administration, endometrial thickness increased with time. Twelve grafted ovarian tissue stimulation cycles led to 4 embryo transfers, the last of which resulted in a live birth. She had 2 cervical cerclage procedures because of cervical shortening and delivered a 3.3-kg healthy female neonate at 38 weeks of gestation via lower-segment cesarean section. Conclusions: Successful pregnancy is possible from ovarian tissue grafted into an irradiated pelvis, with high-dose uterine exposure. Careful uterine assessment needs to be undertaken to determine suitability of conception attempt with a patient's own uterus, in consultation with the medical team. Further studies are needed to correlate imaging and biopsy findings with reproductive outcomes.

Fertility management after breast cancer diagnosis: a qualitative investigation of women's experiences of and recommendations for professional care.

Breast cancer and its treatment in reproductive-age women can reduce fertility and compromise family formation. To learn about women's experiences of fertility-related cancer care we interviewed 10 women (aged 26-45), at least one year postdiagnosis. Thematic analysis revealed that all women, including one who chose to be child-free, valued fertility and motherhood. They reported experiencing varied fertility-related care, from support for fertility preservation to apparent disregard of their fertility concerns. Women's needs were heterogeneous, but all wanted health care providers to communicate fertility options and avoid assumptions about women's fertility desires while working to extend each woman's life.

Live birth rates in day 5 fresh versus vitrified single blastocyst transfer cycles: A cross-sectional analysis.

Background: The use of frozen embryo transfers (FET) in assisted reproduction has increased worldwide. Controlled ovarian hyperstimulation in a fresh transfer may impair endometrial-embryo synchronicity. However, there is conflicting evidence on live birth rates (LBR) and clinical pregnancy rates (CPR). Objective: To compare LBRs and CPRs between single autologous day 5 fresh vs. vitrified blastocyst transfer cycles, to investigate the impact of controlled ovarian hyperstimulation on embryo-endometrium asynchrony. Materials and Methods: A large cross-sectional analysis of 6002 embryo transfers (ET) comprised 3774 fresh and 2228 FET cycles from 2016 to 2019. Multivariate and subgroup analysis were performed for high responders ( > 20 oocytes). Results: Univariate analysis showed no difference in LBR (28.3% vs. 27.4%, p = 0.43) and CPR (32.2% vs. 30.9%, p = 0.30); however, multivariate analysis demonstrated significantly lower LBR (OR 0.864, p = 0.046, 95% CI 0.749-0.997) and CPR (OR 0.852, p = 0.024, 95% CI 0.742-0.979) in FET compared to fresh ETs. Younger participant age, previous in vitro fertilization pregnancy, advanced blastocyst expansion, higher trophectoderm quality, and lower cumulative number of ETs all improved the odds of LBR and CPR. Conventional in vitro fertilization, rather than intracytoplasmic sperm injection, improved CPR but not LBR. Body mass index affected neither LBR nor CPR. In the subgroup, multivariate analysis of high responders showed no difference in LBR or CPR. Conclusion: This study demonstrates relatively higher LBR and CPR of nearly 14% for fresh ETs compared to FETs, in multivariate analysis. A universal freeze-all strategy, without appropriate indication, may lead to suboptimal outcomes. In high responders, freeze-all cycles may be beneficial, as outcomes appear similar.

Stem Cells and Organs-on-chips: New Promising Technologies for Human Infertility Treatment.

Having biological children remains an unattainable dream for most couples with reproductive failure or gonadal dysgenesis. The combination of stem cells with gene editing technology and organ-on-a-chip models provides a unique opportunity for infertile patients with impaired gametogenesis caused by congenital disorders in sex development or cancer survivors. But how will these technologies overcome human infertility? This review discusses the regenerative mechanisms, applications, and advantages of different types of stem cells for restoring gametogenesis in infertile patients, as well as major challenges that must be overcome before clinical application. The importance and limitations of in vitro generation of gametes from patient-specific human-induced pluripotent stem cells (hiPSCs) will be discussed in the context of human reproduction. The potential role of organ-on-a-chip models that can direct differentiation of hiPSC-derived primordial germ cell-like cells to gametes and other reproductive organoids is also explored. These rapidly evolving technologies provide prospects for improving fertility to individuals and couples who experience reproductive failure.