Platelet-rich plasma infusion as an adjunct treatment for persistent thin lining in frozen embryo transfer cycles: first US experience report.

PURPOSE: To study effect of intrauterine infusion of platelet-rich plasma (PRP) on endometrial growth in the setting of thin endometrial lining in patients with prior cancelled or failed frozen embryo transfer (FET) cycles. MATERIALS AND METHODS: Single-arm cohort study of forty-six patients (51 cycles) with endometrial lining thickness (EMT) < 6 mm in prior cancelled or failed FET cycles requesting intrauterine PRP treatment in upcoming FET cycle. The primary outcomes were final EMT in FET cycle and change in EMT after PRP. The secondary outcomes were overall pregnancy rate, clinical pregnancy rate, miscarriage rate, ongoing pregnancy, and live birth rates. RESULTS: The mean pre-PRP EMT in all FET cycles was 4.0 ± 1.1 mm, and mean post-PRP EMT (final) was 7.1 ± 1.0 mm. Of 51 cycles, 33 (64.7%) reached ≥ 7 mm after PRP administration. There was a significant difference between pre-PRP EMT and post-PRP EMT in all FET cycles, with mean difference of 3.0 ± 1.5 mm. Three cycles were cancelled for failure to reach adequate lining. Total pregnancy rate was 72.9% in our cohort of 48 cycles that proceeded to transfer. Clinical pregnancy rate was 54.2% (26/48 FET cycles); clinical miscarriage rate was 14.3% (5/35 pregnancies). Twenty six women had live birth (18 with EMT ≥ 7 mm and 8 with EMT < 7 mm). Response to PRP was not correlated with any pre-cycle characteristics. CONCLUSION: We demonstrate a significant improvement in lining thickness and pregnancy rates in this challenging cohort of women after PRP infusion, with no adverse events. Cost-effectiveness of PRP with benefits and alternatives should be carefully considered.

Fertility issues in hypopituitarism.

Women with hypopituitarism have lower fertility rates and worse pregnancy outcomes than women with normal pituitary function. These disparities exist despite the use of assisted reproductive technologies and hormone replacement. In women with hypogonadotropic hypogonadism, administration of exogenous gonadotropins can be used to successfully induce ovulation. Growth hormone replacement in the setting of growth hormone deficiency has been suggested to potentiate reproductive function, but its routine use in hypopituitary women remains unclear and warrants further study. In this review, we will discuss the clinical approach to fertility in a woman with hypopituitarism.

Pregnancy and neonatal outcomes of letrozole versus natural cycle frozen embryo transfer of autologous euploid blastocyst.

PURPOSE: To investigate the pregnancy and neonatal outcomes of letrozole-stimulated frozen embryo transfer (LTZ-FET) cycles compared with natural FET cycles (NC-FET). METHODS: Our retrospective cohort included all LTZ-FET (n = 161) and NC-FET (n = 575) cycles that transferred a single euploid autologous blastocyst from 2016 to 2020 at Stanford Fertility Center. The LTZ-FET protocol entailed 5 mg of daily letrozole for 5 days starting on cycle day 2 or 3. Outcomes were compared using absolute standardized differences (ASD), in which a larger ASD signifies a larger difference. Multivariable regression models adjusted for confounders: maternal age, BMI, nulliparity, embryo grade, race, infertility diagnosis, and endometrial thickness. RESULTS: The demographic and clinical characteristics were overall similar. A greater proportion of the letrozole cohort was multiparous, transferred high-graded embryos, and had ovulatory dysfunction. The cohorts had similar pregnancy rates (67.1% LTZ vs 62.1% NC; aOR 1.31, P = 0.21) and live birth rates (60.9% LTZ vs 58.6% NC; aOR 1.17, P = 0.46). LTZ-FET neonates on average were born 5.7 days earlier (P < 0.001) and had higher prevalence of prematurity (18.6% vs. 8.0%NC, ASD = 0.32) and low birth weight (10.4% vs. 5.0%, ASD = 0.20). Both cohorts' median gestational ages (38 weeks and 1 day for LTZ; 39 weeks and 0 day for NC) were full term. CONCLUSION: There were similar rates of pregnancy and live birth between LTZ-FET and NC-FET cycles. However, there was a higher prevalence of prematurity and low birth weight among LTZ-FET neonates. Reassuringly, the median gestational age in both cohorts was full term, and while the difference in gestational length of almost 6 days does not appear to be clinically significant, this warrants larger studies.

REPRODUCTIVE OPHTHALMOLOGY: The Intersection of Inherited Eye Diseases and Reproductive Technologies.

PURPOSE: To propose a working framework for patients with inherited eye diseases presenting to ophthalmologists who are interested in assisted reproductive technology and preimplantation genetic testing. METHODS: Retrospective chart review and case series of three families with inherited eye diseases who successfully underwent preimplantation genetic testing, in vitro fertilization, and birth of unaffected children. RESULTS: Preimplantation genetic testing was performed for three families with different inherited eye diseases, which included autosomal dominant retinitis pigmentosa, autosomal recessive achromatopsia, and X-linked Goltz syndrome. Preimplantation genetic testing led to the identification of unaffected embryos, which were then selected for in vitro fertilization and resulted in the birth of unaffected children. CONCLUSION: A close collaboration between patients, families, ophthalmologists, reproductive genetic counselors, and reproductive endocrinology and infertility specialists is the ideal model for taking care of patients interested in preimplantation genetic testing for preventing the transmission of inherited eye diseases.

Analysing endometrial microbiome: methodological considerations and recommendations for good practice.

There is growing evidence that the upper female genital tract is not sterile, harbouring its own microbial communities. However, the significance and the potential effect of endometrial microorganisms on reproductive functions remain to be fully elucidated. Analysing the endometrial microbiome, the microbes and their genetic material present in the endometrium, is an emerging area of study. The initial studies suggest it is associated with poor reproductive outcomes and with different gynaecological pathologies. Nevertheless, studying a low-biomass microbial niche as is endometrium, the challenge is to conduct well-designed and well-controlled experiments in order to avoid and adjust for the risk of contamination, especially from the lower genital tract. Herein, we aim to highlight methodological considerations and propose good practice recommendations for future endometrial microbiome studies.

Autologous platelet-rich plasma treatment for moderate-severe Asherman syndrome: the first experience.

PURPOSE: Treatment of Asherman syndrome (AS) presents a significant clinical challenge. Based on our in vitro data showing that PRP could activate endometrial cell proliferation and migration, we hypothesized that intrauterine infusion of autologous platelet-rich plasma (PRP) may improve endometrial regeneration and fertility outcomes in patients with moderate-severe AS. MATERIALS AND METHODS: Subjects with moderate-severe AS were randomized to PRP or saline control administered following hysteroscopic adhesiolysis. Due to relative inability to randomize patients to the control group, after initial randomization of 10 subjects (6 in PRP and 4 in control groups), the remainder were prospectively enrolled in PRP group (n = 9), with 11 historic controls added to control group, for a total of 30 subjects (PRP n = 15; saline control n = 15). Right after hysteroscopy, 0.5-1 mL of PRP or saline was infused into the uterus via a Wallace catheter, followed by estrogen therapy. The primary outcomes were changes in endometrial thickness (EMT, checked in 3 weeks) and in menstrual flow; secondary outcomes were pregnancy and live birth rates. EMT and menstrual bleeding pattern were assessed before and after the intervention. Pregnancy was assessed over a 6-month period. RESULTS: There were no statistically significant differences in age, gravidity/parity, cause of AS, preoperative menses assessment, AS hysteroscopy score, and intrauterine balloon placement between the groups. There was no statistically significant difference (p = 0.79) in EMT pre-PRP infusion for control (5.7 mm, 4.0-6.0) and study arm (5.3 mm, 4.9-6.0). There was no statistically significant change (p = 0.78) in EMT after PRP infusion (1.4 mm, - 0.5-2.4) vs saline (1.0 mm, 0.0-2.5). Patients tolerated the procedure well, with no adverse effects. There was no difference in the predicted likelihood of pregnancy (p = 0.45) between the control (0.67, 0.41-0.85) and study arm (0.53, 0.29-0.76). CONCLUSIONS: PRP was well accepted and tolerated in AS patients. However, we did not observe any significant EMT increase or improved pregnancy rates after adding PRP infusion, compared to standard treatment only. The use of intrauterine PRP infusion may be a feasible option, and its potential use must be tested on a larger sample size of AS patients.

We are here for you: infertility clinic communication during the first wave of the COVID-19 pandemic.

PURPOSE: To study how SART-member fertility clinics communicated via clinic websites during the first wave of the COVID-19 pandemic following publication of ASRM COVID-19 Task Force recommendations. METHODS: SART-member fertility clinic websites were systematically surveyed for the presence of an REI-specific COVID-19 message (REI-CM) and analyzed for their adherence to ASRM guidance. RESULTS: Of the 381 active clinic websites, 249 (65.3%) had REI-specific COVID messaging. The presence of REI-CM was more common in private than in academic practices (73% vs 38%, p < 0.001) and with increasing practice volume: 38% of clinics with < 200 annual cycles vs 91% of clinics with > 1000 cycles (p < 0.001). Adherence to ASRM guidance was more common in academic than in private practices (54% vs 31%, p = 0.02). Additionally, 9% of REI-CM (n = 23) announced continued treatment regardless of a patient's clinical urgency. This messaging was more common in groups doing > 1000 cycles a year (18%, p = 0.009). Clinics treating all-comers were less likely to cite ASRM than other clinics (41% vs 62%, p = 0.045). However, 75% (n = 14) cited COVID-19 guidance from WHO, CDC, and state and local governments. CONCLUSIONS: Clinic response to ASRM recommendations during the first wave of COVID-19 pandemic was heterogeneous. Although academic practices were more likely to follow ASRM guidance, there was a lower extent of patient-facing messaging among academic practices than private clinics. In event of further escalations of this and future pandemics, clinics can learn from experiences to provide clear messaging to patients.

Cross-disorder analysis of endometriosis and its comorbid diseases reveals shared genes and molecular pathways and proposes putative biomarkers of endometriosis.

RESEARCH QUESTION: Women with endometriosis are considered to be at higher risk of several chronic diseases, such as autoimmune disorders, gynaecological cancers, asthma/atopic diseases and cardiovascular and inflammatory bowel diseases. Could the study of endometriosis-associated comorbidities help to identify potential biomarkers and target pathways of endometriosis? DESIGN: A systematic review was performed to identify all possible endometriosis-associated comorbid conditions. Next, this list of disorders was coded into MeSH terms, and the gene expression profiles were downloaded from the Phenopedia database and subsequently analysed following a systems biology approach. RESULTS: The results identified a group of 127 candidate genes that were recurrently expressed in endometriosis and its closest comorbidities and that were defined as 'endometriosis sibling disorders' (ESD). The enrichment analysis showed that these candidate genes are principally involved in immune and drug responses, hormone metabolism and cell proliferation, which are well-known hallmarks of endometriosis. The expression of ESD genes was then validated on independent sample cohorts (n = 207 samples), in which the involvement of 16 genes (AGTR1, BDNF, C3, CCL2, CD40, CYP17A1, ESR1, IGF1, IGF2, IL10, MMP1, MMP7, MMP9, PGR, SERPINE1 and TIMP2) in endometriosis was confirmed. Several of these genes harbour polymorphisms that associate to either endometriosis or its comorbid conditions. CONCLUSIONS: The study results highlight the molecular processes underlying the aetiopathogenesis of endometriosis and its comorbid conditions, and identify putative endometriosis biomarkers.

Correction to: How good are we at modeling implantation?

The original article unfortunately contained a mistake. The name of the author should be Lusine Aghajanova instead of Aghajanova Lusine.

Levonorgestrel IUD: is there a long-lasting effect on return to fertility?

Intrauterine devices (IUDs) are effective and safe long-acting reversible contraceptive methods for preventing unplanned pregnancies. While extensive studies were conducted to evaluate return to fertility after removal of IUDs, majority of them were focused on multiparous women using copper IUDs. Current trends indicate increased use of levonorgestrel (LNG) IUDs in nulliparous women for very long periods of time, with both nulliparity and long duration of LNG-IUD use being potentially associated with trends towards longer time to conception post removal. Understanding the effects that LNG-IUDs may have on endometrial morphology and gene expression has important implications to further understanding their mechanism of action. Studies examining endometrial gene expression show persistent changes in receptivity markers up to 1 year after removal of an inert IUD, and no similar studies have been performed after removal of LNG-IUDs. Given the current gap in the literature and trends in LNG-IUD use in nulliparous young women, studies are needed that specifically look at the interaction of nulliparity, long-term use of LNG-IUD, and return to normal fertility. Herein, we review the available literature on the mechanism of action of IUDs with a specific focus on the effect on endometrial gene expression profile changes associated with IUDs.

In vitro evidence that platelet-rich plasma stimulates cellular processes involved in endometrial regeneration.

PURPOSE: The study aims to test the hypothesis that platelet-rich plasma (PRP) stimulates cellular processes involved in endometrial regeneration relevant to clinical management of poor endometrial growth or intrauterine scarring. METHODS: Human endometrial stromal fibroblasts (eSF), endometrial mesenchymal stem cells (eMSC), bone marrow-derived mesenchymal stem cells (BM-MSC), and Ishikawa endometrial adenocarcinoma cells (IC) were cultured with/without 5% activated (a) PRP, non-activated (na) PRP, aPPP (platelet-poor-plasma), and naPPP. Treatment effects were evaluated with cell proliferation (WST-1), wound healing, and chemotaxis Transwell migration assays. Mesenchymal-to-epithelial transition (MET) was evaluated by cytokeratin and vimentin expression. Differential gene expression of various markers was analyzed by multiplex Q-PCR. RESULTS: Activated PRP enhanced migration of all cell types, compared to naPRP, aPPP, naPPP, and vehicle controls, in a time-dependent manner (p < 0.05). The WST-1 assay showed increased stromal and mesenchymal cell proliferation by aPRP vs. naPRP, aPPP, and naPPP (p < 0.05), while IC proliferation was enhanced by aPRP and aPPP (p < 0.05). There was no evidence of MET. Expressions of MMP1, MMP3, MMP7, and MMP26 were increased by aPRP (p < 0.05) in eMSC and eSF. Transcripts for inflammation markers/chemokines were upregulated by aPRP vs. aPPP (p < 0.05) in eMSC and eSF. No difference in estrogen or progesterone receptor mRNAs was observed. CONCLUSIONS: This is the first study evaluating the effect of PRP on different human endometrial cells involved in tissue regeneration. These data provide an initial ex vivo proof of principle for autologous PRP to promote endometrial regeneration in clinical situations with compromised endometrial growth and scarring.

Effects of noncavity-distorting fibroids on endometrial gene expression and function.

Uterine fibroids are a common finding in infertility patients. Impaired implantation and decidualization have been proposed to contribute to compromised fertility. Data are limited on the endometrial transcriptome from subjects with uterine fibroids, as well as endometrial receptivity and decidualization potential of endometrial stromal fibroblasts (eSF) from women with fibroids. Our objective was to investigate the endometrial transcriptome of women with noncavity-distorting intramural fibroids and compare them to control subjects with no uterine pathology throughout the menstrual cycle. We also evaluated endometrial receptivity gene expression and basic endometrial functions such as decidualization, proliferation, and apoptosis in women with fibroid uterus. Results showed that large numbers of transcripts were significantly dysregulated throughout the menstrual cycle in fibroid subjects compared to controls. However, there were essentially no differences in the expression of receptivity markers at the tissue level, as well as decidualization markers in tissue and eSF in subjects with fibroids compared to controls. However, eSF from women with a fibroid uterus exhibited decreased proliferation potential and increased apoptosis upon decidualization. These data indicate preserved implantation and decidualization potential despite observed gene expression changes in endometrium from women with noncavity-distorting fibroids compared to controls. How this phenomenon and altered proliferation/apoptosis may contribute to impairment of endometrial function in subfertile patients warrants further investigation.

Prepubertal Gynecomastia Due to Indirect Exposure to Nonformulary Bioidentical Hormonal Replacement Therapy: A Case Report.

BACKGROUND: Gynecomastia is a disorder of the endocrine system characterized by an abnormal presence of a palpable unilateral or bilateral enlargement and proliferation of glandular ductal benign breast tissue in male individuals. This case discusses the medical implications of an unregulated, indirect exposure to nonformulary, bioidentical hormone replacement therapy in male children. CASE: An 8-year-old boy presented with prepubertal gynecomastia secondary to estrogen exposure from maternal use of bioidentical hormonal replacement therapy (the Wiley protocol). We review the literature on prepubertal gynecomastia secondary to exogenous estrogen exposure, evaluation, clinical surveillance of the pubertal development, and relevant short- and long-term implications. CONCLUSION: Indirect exposure to nonformulary hormonal replacement in our case report was an etiologic factor in the development of prepubertal gynecomastia. This novel estrogen exposure source has important implications in the differential diagnosis of prepubertal gynecomastia and potential adverse effects secondary to precocious hormonal exposure.

Birth of a healthy child after preimplantation genetic screening of embryos from sperm of a man with non-mosaic Down syndrome.

PURPOSE: The purpose of this study is to present a case of healthy infant born after intracytoplasmic sperm injection-in vitro fertilization (ICSI-IVF) with preimplantation genetic screening (PGS) using sperm from a man with non-mosaic trisomy 21 and a literature review. MATERIALS AND METHODS: A 26-year-old euploid female and 29-year-old male with non-mosaic trisomy 21 and male factor undergoing ICSI-IVF treatment for primary infertility with embryo biopsy for PGS with comprehensive chromosomal screening (CCS) presented to the Infertility Clinic at Highland Hospital, the Alameda County Medical Center, California, with 6-year history of primary infertility. The outcome measure is a live birth of a healthy child and ploidy status of biopsied blastocysts. RESULTS: Egg retrieval yielded 33 oocytes, 29 of which underwent ICSI with ejaculated sperm. Twenty-eight 2PN zygotes were cultured, and 13 blastocysts underwent trophectoderm biopsy and vitrification 5 or 6 days after retrieval. CCS analysis revealed that 12 out of 13 (92 %) of blastocysts were euploid and one was a complex abnormal mosaic. Transfer of two grade I hatching blastocysts resulted in a singleton pregnancy with normal prenatal genetic screening and delivery of a healthy male infant at 41 weeks via primary cesarean section for non-reassuring fetal status. CONCLUSION: This is the first report of a live birth of a healthy child after ICSI-IVF with PGS using ejaculated sperm from a man with non-mosaic trisomy 21 and male factor infertility.

The impact of estradiol supplementation on endometrial thickness and intrauterine insemination outcomes.

The impact of estrogen supplementation during the follicular/proliferative phase on the endometrial lining thickness (EMT) prior to intrauterine insemination (IUI) remains largely unstudied. Our study examined changes in EMT and rates of clinical pregnancy, miscarriage, and live birth for all patients who completed an IUI cycle at Stanford Fertility Center from 2017-2023 (n = 2281 cycles). Cycles with estradiol supplementation (n = 309) were compared to reference cycles without supplementation (n = 1972), with the reference cohort further categorized into cycles with a pre-ovulatory EMT of < 7 mm ("thin-lining", n = 536) and ≥ 7 mm ("normal-lining", n = 1436). The estradiol group had a statistically significant greater change in EMT from baseline to ovulation compared to the thin-lining reference groups (2.4 mm vs 1.9 mm, p < =0.0001). Similar rates of clinical pregnancy and live birth were observed. After adjusting for age, BMI, race/ethnicity, infertility diagnosis, and EMT at trigger, the estradiol cohort had a significantly increased odds of miscarriage versus the entire reference cohort (2.46, 95 % confidence interval [1.18, 5.14], p = 0.02). Thus, although estradiol supplementation had a statistically significant increase in EMT compared to IUI cycles with thin pre-ovulatory EMT (<7 mm), this change did not translate into improved IUI outcomes such as increased rates of clinical pregnancy and live birth or decreased rate of miscarriage. Our study suggests that supplemental estradiol does not appear to improve IUI outcomes.

Comparative transcriptome analysis of human trophectoderm and embryonic stem cell-derived trophoblasts reveal key participants in early implantation.

The implantation process begins with attachment of the trophectoderm (TE) of the blastocyst to the maternal endometrial epithelium. Herein we have investigated the transcriptome of mural TE cells from 13 human blastocysts and compared these with those of human embryonic stem cell (hESC)-derived-TE (hESC(troph)). The transcriptomes of hESC(troph) at Days 8, 10, and 12 had the greatest consistency with TE. Among genes coding for secreted proteins of the TE of human blastocysts and of hESC(troph) are several molecules known to be involved in the implantation process, as well as novel ones, such as CXCL12, HBEGF, inhibin A, DKK3, WNT5A, and follistatin. The similarities between the two lineages underscore some of the known mechanisms and offer discovery of new mechanisms and players in the process of the very early stages of human implantation. We propose that the hESC(troph) is a viable functional model of human trophoblasts to study trophoblast-endometrial interactions. Furthermore, the data derived herein offer the promise of novel diagnostics and therapeutics aimed at practical challenges in human infertility and pregnancy disorders associated with abnormal embryonic implantation.

Perivascular human endometrial mesenchymal stem cells express pathways relevant to self-renewal, lineage specification, and functional phenotype.

Human endometrium regenerates on a cyclic basis from candidate stem/progenitors whose genetic programs are yet to be determined. A subpopulation of endometrial stromal cells, displaying key properties of mesenchymal stem cells (MSCs), has been characterized. The endometrial MSC (eMSC) is likely the precursor of the endometrial stromal fibroblast. The goal of this study was to determine the transcriptome and signaling pathways in the eMSC to understand its functional phenotype. Endometrial stromal cells from oocyte donors (n = 20) and patients undergoing benign gynecologic surgery (n = 7) were fluorescence-activated cell sorted into MCAM (CD146)(+)/PDGFRB(+) (eMSC), MCAM (CD146)(-)/PDGFRB(+) (fibroblast), and MCAM (CD146)(+)/PDGFRB(-) (endothelial) populations. The eMSC population contained clonogenic cells with a mesenchymal phenotype differentiating into adipocytes when cultured in adipogenic medium. Gene expression profiling using Affymetrix Human Gene 1.0 ST arrays revealed 762 and 1518 significantly differentially expressed genes in eMSCs vs. stromal fibroblasts and eMSCs vs. endothelial cells, respectively. By principal component and hierarchical clustering analyses, eMSCs clustered with fibroblasts and distinctly from endothelial cells. Endometrial MSCs expressed pericyte markers and were localized by immunofluorescence to the perivascular space of endometrial small vessels. Endometrial MSCs also expressed genes involved in angiogenesis/vasculogenesis, steroid hormone/hypoxia responses, inflammation, immunomodulation, cell communication, and proteolysis/inhibition, and exhibited increased Notch, TGFB, IGF, Hedgehog, and G-protein-coupled receptor signaling pathways, characteristic of adult tissue MSC self-renewal and multipotency. Overall, the data support the eMSC as a clonogenic, multipotent pericyte that displays pathways of self-renewal and lineage specification, the potential to respond to conditions during endometrial desquamation and regeneration, and a genetic program predictive of its differentiated lineage, the stromal fibroblast.

Fertility Preservation for Transgender Males: Counseling and Timing of Treatment.

Fertility-preservation counseling in the transgender patient population is recommended by multiple organizations, including the American Society for Reproductive Medicine, the World Professional Association for Transgender Health, and the Endocrine Society. The optimal time to pursue fertility preservation has not been established, and data on potential effects of testosterone therapy on future reproductive potential are limited. This Current Commentary seeks to elucidate the most appropriate time to perform oocyte cryopreservation in relation to time on and off testosterone therapy, age of the individual, and emotional effect of treatment. Although there have been multiple studies that have demonstrated successful oocyte cryopreservation regardless of testosterone exposure, the data on live-birth rates after oocyte cryopreservation are limited. Moreover, the process of oocyte cryopreservation may have a significant negative emotional effect on the transgender male given the feminizing effects of gonadotropin stimulation, as well as the invasiveness of pelvic ultrasonograms and the oocyte-retrieval procedure. With our review, we demonstrate that a comprehensive, individualized approach to fertility-preservation counseling and timing to pursue treatment are essential. Postponing fertility-preservation procedures until patients have reached early adulthood might be considered to avoid the potential effect on mental health, without compromising outcomes.

The Effect of Human Growth Hormone on Endometrial Growth in Controlled Ovarian Hyperstimulation Cycles.

This study aims to compare endometrial growth before and after the addition of human growth hormone (hGH) in controlled ovarian hyperstimulation (COH) cycles. A 5-year retrospective cohort study of patients treated with hGH to improve oocyte development during COH cycles was conducted. Each patient's cycle without hGH immediately preceding cycle(s) with hGH was used for patients to serve as their own controls. Primary outcome was absolute growth in endometrial thickness from pre-stimulation start to day of hCG trigger. Mixed-model regression analysis controlled for patient correlation over repeat cycles and potential confounders. 80 patients were included. Mean age was 39.7 years; mean BMI was 23.8 kg/m2. Majority of patients were nulliparous, non-smoking, and White or Asian. Most common diagnosis was diminished ovarian reserve. Endometrial growth was compared between 159 COH cycles with hGH and 80 COH control cycles; mean increase was 4.5 mm and 3.9 mm, respectively-an unadjusted difference of 0.6 mm (95% CI: 0.2−1.1, p = 0.01). After adjusting for demographic/clinical factors, hGH was associated with 0.9 mm greater endometrial growth (0.4−1.4, p < 0.01). Absolute increase in endometrial thickness was higher in COH cycles that included hGH. Further prospective studies in embryo transfer cycles are needed.