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Wei C, Wu H, Yu Y, Li Y, Xiang S, Lian F. Effect of estrogen exposure on pregnancy outcomes in artificial frozen-thawed embryo transfer cycles. Gynecol Endocrinol 2024; 40:2352142. [PMID: 38781518 DOI: 10.1080/09513590.2024.2352142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 04/24/2024] [Indexed: 05/25/2024] Open
Abstract
In contemporary times, the employment of vitrification freezing technology has led to the widespread adoption of frozen-thawed embryo transfer (FET) worldwide. Meanwhile, hormone replacement therapy (HRT) is a crucial protocol for priming the endometrium during FET cycles. Estrogen is required in HRT cycles for the induction of progesterone receptors and to promote endometrial thickness. However, there is no universal consensus on the treatment duration, dosage regimen, administration route, and target serum estrogen levels. Therefore, this study aimed to offer a comprehensive review of these topics. A shorter duration of estrogen exposure may elevate the risk of early miscarriage, while prolonged exposure to estrogen does not seem to confer advantages to general population and may be attempted in individuals with thin endometrium. Moreover, excessive estrogen levels on the day of progesterone administration may be associated with higher miscarriage rates and lower live birth rates (LBR). To offer more comprehensive guidance for clinical practice, extensive and prospective studies involving a large sample size are warranted to determine the optimal concentration and duration of estrogen exposure.
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Affiliation(s)
- Chaofeng Wei
- First College of Clinical Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Haicui Wu
- Integrative Medicine Research Centre of Reproduction and Heredity, The Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Yi Yu
- Integrative Medicine Research Centre of Reproduction and Heredity, The Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Yuan Li
- Integrative Medicine Research Centre of Reproduction and Heredity, The Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Shan Xiang
- First College of Clinical Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Fang Lian
- Integrative Medicine Research Centre of Reproduction and Heredity, The Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
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Stevens Brentjens LBPM, Obukhova D, den Hartog JE, Delvoux B, Koskivuori J, Auriola S, Häkkinen MR, Bui BN, van Hoogenhuijze NE, Mackens S, Mol F, de Bruin JP, Besselink D, Teklenburg G, Kukushkina V, Salumets A, Broekmans FJM, van Golde RJT, Esteki MZ, Romano A. An integrative analysis of endometrial steroid metabolism and transcriptome in relation to endometrial receptivity in in vitro fertilization patients. F&S SCIENCE 2023; 4:219-228. [PMID: 37142054 DOI: 10.1016/j.xfss.2023.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/27/2023] [Accepted: 04/24/2023] [Indexed: 05/06/2023]
Abstract
OBJECTIVE To study the relationship between the steroid concentration in the endometrium, in serum, and the gene expression level of steroid-metabolizing enzymes in the context of endometrial receptivity in in vitro fertilization (IVF) patients. DESIGN Case-control study of 40 IVF patients recruited in the SCRaTCH study (NTR5342), a randomized controlled trial investigating pregnancy outcome after "endometrial scratching." Endometrial biopsies and serum were obtained from patients with a first failed IVF cycle randomized to the endometrial scratch in the midluteal phase of the natural cycle before the next fresh embryo transfer during the second IVF cycle. SETTING University hopsital. PATIENTS Twenty women with clinical pregnancy were compared with 20 women who did not conceive after fresh embryo transfer. Cases and controls were matched for primary vs. secondary infertility, embryo quality, and age. INTERVENTION None. MAIN OUTCOME MEASURE(S) Steroid concentrations in endometrial tissue homogenates and serum were measured with liquid chromatography-mass spectrometry. The endometrial transcriptome was profiled by RNA-sequencing, followed by principal component analysis and differential expression analysis. False discovery rate-adjusted and log-fold change >|0.5| were selected as the threshold for differentially expressed genes. RESULT(S) Estrogen levels were comparable in both serum (n = 16) and endometrium (n = 40). Androgens and 17-hydroxyprogesterone were higher in serum than that in endometrium. Although steroid levels did not vary between pregnant and nonpregnant groups, subgroup analysis of primary women with infertility showed a significantly lower estrone concentration and estrone:androstenedione ratio in serum of the pregnant group (n = 5) compared with the nonpregnant group (n = 2). Expression of 34 out of 46 genes encoding the enzymes controlling the local steroid metabolism was detected, and estrogen receptor β gene was differentially expressed between pregnant and nonpregnant women. When only the primary infertile group was considered, 28 genes were differentially expressed between pregnant and nonpregnant women, including HSD11B2, that catalyzes the conversion of cortisol into cortisone. CONCLUSION(S) Steroidomic and transcriptomic analyses show that steroid concentrations are regulated by the local metabolism in the endometrium. Although no differences were found in endometrial steroid concentration in the pregnant and nonpregnant IVF patients, primary women with infertility showed deviations in steroid levels and gene expression, indicating that a more homogeneous patient group is required to uncover the exact role of steroid metabolism in endometrial receptivity. CLINICAL TRIAL REGISTRATION NUMBER The study was registered in the Dutch trial registry (www.trialregister.nl), registration number NL5193/NTR5342, available at https://trialsearch.who.int/Trial2.aspx?TrialID=NTR6687. The date of registration is July 31, 2015. The first enrollment is on January 1, 2016.
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Affiliation(s)
- Linda B P M Stevens Brentjens
- Department of Obstetrics and Gynecology, Maastricht University Medical Center+, Maastricht, the Netherlands; GROW School for Oncology and Reproduction, Maastricht University, Maastricht, the Netherlands.
| | - Darina Obukhova
- GROW School for Oncology and Reproduction, Maastricht University, Maastricht, the Netherlands; Department of Clinical Genetics, Maastricht University, Maastricht, the Netherlands
| | - Janneke E den Hartog
- Department of Obstetrics and Gynecology, Maastricht University Medical Center+, Maastricht, the Netherlands; GROW School for Oncology and Reproduction, Maastricht University, Maastricht, the Netherlands
| | - Bert Delvoux
- Department of Obstetrics and Gynecology, Maastricht University Medical Center+, Maastricht, the Netherlands; GROW School for Oncology and Reproduction, Maastricht University, Maastricht, the Netherlands
| | | | - Seppo Auriola
- University of Eastern Finland, School of Pharmacy, Kuopio, Finland
| | - Merja R Häkkinen
- Department of Health Security, Finnish Institute for Health and Welfare (THL), Kuopio, Finland
| | - Bich N Bui
- Department of Gynecology and Reproductive Medicine, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Nienke E van Hoogenhuijze
- Department of Gynecology and Reproductive Medicine, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Shari Mackens
- Center for Reproductive Medicine, UZ Brussel, Jette, Belgium
| | - Femke Mol
- Center for Reproductive Medicine, Reproduction and Development, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Jan Peter de Bruin
- Department of Obstetrics and Gynecology, Jeroen Bosch Hospital-Hertogenbosch, the Netherlands
| | - Dagmar Besselink
- Department of Obstetrics and Gynecology, Radboud University Medical Centre, Nijmegen, the Netherlands
| | - Gijs Teklenburg
- Isala Fertility Clinic, Isala Hospital, Zwolle, the Netherlands
| | | | - Andres Salumets
- Competence Centre on Health Technologies, Tartu, Estonia; Department of Obstetrics and Gynecology, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia; Division of Obstetrics and Gynecology, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
| | - Frank J M Broekmans
- Department of Gynecology and Reproductive Medicine, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Ron J T van Golde
- Department of Obstetrics and Gynecology, Maastricht University Medical Center+, Maastricht, the Netherlands; GROW School for Oncology and Reproduction, Maastricht University, Maastricht, the Netherlands
| | - Masoud Zamani Esteki
- GROW School for Oncology and Reproduction, Maastricht University, Maastricht, the Netherlands; Department of Clinical Genetics, Maastricht University, Maastricht, the Netherlands
| | - Andrea Romano
- Department of Obstetrics and Gynecology, Maastricht University Medical Center+, Maastricht, the Netherlands; GROW School for Oncology and Reproduction, Maastricht University, Maastricht, the Netherlands
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Li Q, Ruan L, Zhu L, Yang Z, Zhu M, Luo Y. Elevated estradiol levels in frozen embryo transfer have different effects on pregnancy outcomes depending on the stage of transferred embryos. Sci Rep 2022; 12:5592. [PMID: 35379862 PMCID: PMC8980097 DOI: 10.1038/s41598-022-09545-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 03/24/2022] [Indexed: 11/09/2022] Open
Abstract
Supplementation with estradiol (E2) is routinely used in frozen embryo transfer (FET) cycles and embryo age plays an important role in conceiving. This study was to compare the effects of serum E2 levels on pregnancy outcomes between cleavage- and blastocyst-stage FET cycles using hormone replacement therapy. A total of 776 FET cycles (669 couples) performed from January 2016 to December 2019 were included in the present retrospective cohort study. Regarding cleavage-stage embryo transfers, E2 levels on progesterone initiation day were significantly lower in the ongoing pregnancy/live birth (OP/LB) group than in the non-OP/LB group (214.75 ± 173.47 vs. 253.20 ± 203.30 pg/ml; P = 0.023). In addition, there were downward trends in implantation, clinical pregnancy and OP/LB rates with increasing E2 levels. However, in blastocyst-stage embryo transfers, such trends were not observed, and E2 levels were not significant difference between the OP/LB group and the non-OP/LB group (201.66 ± 182.14 vs. 197.89 ± 212.83 pg/ml; P = 0.884). The results suggests that elevated progesterone-initiation-day E2 levels may negatively affect pregnancy outcomes during artificial cleavage-stage embryo transfers. However, it is not necessary to monitor E2 levels when transferring blastocysts in artificial FET cycles.
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Affiliation(s)
- Qing Li
- Reproductive Medicine Center, Nanning Maternity and Child Health Hospital, Nanning, 530011, China
| | - Liming Ruan
- Reproductive Medicine Center, Nanning Maternity and Child Health Hospital, Nanning, 530011, China
| | - Lingling Zhu
- Reproductive Medicine Center, Yulin Maternity and Child Health Hospital, Yulin, 537000, China
| | - Zengyu Yang
- Reproductive Medicine Center, Yulin Maternity and Child Health Hospital, Yulin, 537000, China
| | - Maoling Zhu
- Reproductive Medicine Center, Nanning Maternity and Child Health Hospital, Nanning, 530011, China.
| | - Yudi Luo
- Reproductive Medicine Center, Yulin Maternity and Child Health Hospital, Yulin, 537000, China.
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Identification of the Metabolomics Signature of Human Follicular Fluid from PCOS Women with Insulin Resistance. DISEASE MARKERS 2022; 2022:6877541. [PMID: 35465261 PMCID: PMC9019454 DOI: 10.1155/2022/6877541] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Accepted: 02/22/2022] [Indexed: 12/30/2022]
Abstract
Context. Polycystic ovary syndrome (PCOS) is a gynecological endocrine disease, and approximately 60% of patients with PCOS have different degrees of insulin resistance (IR). The regulatory role of metabolic networks in human follicular fluid (FF) related to IR in PCOS remains unclear. Aims. To explore the effect of IR on the metabolism of PCOS by analyzing the changes in FF metabolites in PCOS patients who are undergoing assisted reproductive technology based on the metabonomic platform of ultraperformance gas chromatography coupled to mass spectrometry (GC/MS). Method. Eight PCOS patients with IR (PCOS-IR) and 8 PCOS patients without IR (PCOS-NIR) were enrolled. All patients received controlled ovarian stimulation by using the gonadotropin-releasing hormone (GnRH) antagonist protocol, and the FF of a single dominant follicle was collected on the day of oocyte retrieval. The metabolite profiles of the FF were determined by GC/MS. Key Results. A total of 20 differentially expressed metabolites in FF were identified. Compared with levels in the PCOS-NIR group, stearic acid, palmitic acid, pentadecanoic acid, stigmasterol, citric acid, isocitric acid, thymine, and pyruvic acid in FF were significantly increased in the PCOS-IR group. Lithocholic acid and sinapinic acid in FF decreased significantly. The affected metabolic pathways with potential regulatory roles were identified by KEGG annotation. Conclusion. Compared with the PCOS-NIR group, the PCOS-IR group showed more significant metabolic abnormalities. Implications. These results will help us to understand the pathogenesis of PCOS combined with IR and will provide new clues for studying metabolic disorders associated with PCOS, e.g., IR.
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Garimella S, Karunakaran S, Gedela DR. "Does serum estrogen level have an impact on outcomes in hormonal replacement frozen-warmed embryo transfer cycles?". Gynecol Endocrinol 2021; 37:891-894. [PMID: 33645401 DOI: 10.1080/09513590.2021.1892631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
AIM To evaluate the impact of serum estradiol (E2) levels on cycle outcomes in hormone replacement frozen embryo transfer (HR- FET) cycles. MATERIALS AND METHODS We retrospectively analyzed 509 HR-FET cycles performed from September 2018 to September 2019. Patients were divided into 6 groups based on their E2 values measured a day before progesterone initiation . Group 1: <100 pg/mL, group 2: 100-200 pg/mL, group 3: 200 - 300 pg/mL, group 4: 300-400 pg/mL, group 5: 400-500 pg/mL, group 6: >500 pg/mL. Implantation rate (IR), clinical pregnancy rate (CPR), miscarriage rate (MR), multiple pregnancy rate (MPR) and ectopic pregnancy rates were compared between all groups. RESULTS IR and CPR were similar between a wide range of E2 values, but when E2 values were more than 500 pg/mL there was a non significant fall in the IR (47.3% vs 48.3% vs 48.6% vs 47.8% vs 48.7% vs 39.6% p = .77) and CPR (63.6% vs 65.1% vs 65.6% vs 65.3% vs 65.6% vs 53.1% p = .692). MR was significantly high when E2 was less than 100 pg/mL (28.5%) and when E2 was more than 500 pg/mL (41.1%) (p = .02). MPR and ectopic pregnancy rates were similar between all the groups. CONCLUSION Outcomes of FET cycles were similar between a wide range of E2 values (100-500 pg/mL). When E2 levels were less than 100 pg/mL or more than 500 pg/mL there was significant increase in the MR but the numbers in these groups are less and further studies are required to confirm these facts.
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Beck-Fruchter R, Nothman S, Baram S, Geslevich Y, Weiss A. Progesterone and estrogen levels are associated with live birth rates following artificial cycle frozen embryo transfers. J Assist Reprod Genet 2021; 38:2925-2931. [PMID: 34537928 DOI: 10.1007/s10815-021-02307-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 08/22/2021] [Indexed: 10/20/2022] Open
Abstract
PURPOSE Does an association exist between serum progesterone and estradiol levels and live birth rates in artificial cycle frozen embryo transfer (AC-FET)? METHODS Retrospective cohort study was based on prospectively collected data at a university-affiliated fertility center. Included were all cycles using an artificial endometrial preparation with estradiol hemihydrate (Estrofem, 2 mg/8 h) and vaginal progesterone (Endometrin 100 mg/8 h), autologous oocytes, and cleavage stage embryo transfers. Serum progesterone and estradiol levels were measured 14 days after FET. A total of 921 cycles in 568 patients from to December 2010 to June 2019 were investigated. Live birth was the primary outcome measure. RESULTS Significant association was found between live birth and progesterone as well as estradiol levels (progesterone 14.65 vs 11.62 ng/ml, p = 0.001; estradiol 355.12 vs 287.67 pg/ml, p = 0.001). A significant difference in live birth rate was found below and above the median progesterone level (10.9 ng/ml, p = 0.007). Lower estradiol level was significantly associated with lower live birth rate (< 188.2 pg/ml 8.3%, > 263.1 pg/ml 16%, p = 0.02). CONCLUSIONS Serum progesterone and estradiol levels impact live birth rate in AC-FET.
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Affiliation(s)
- Ronit Beck-Fruchter
- Fertility Unit, Department of Obstetrics and Gynecology, Emek Medical Center, Afula, Israel. .,Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
| | - Simon Nothman
- Fertility Unit, Department of Obstetrics and Gynecology, Emek Medical Center, Afula, Israel.,Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
| | - Shira Baram
- Fertility Unit, Department of Obstetrics and Gynecology, Emek Medical Center, Afula, Israel
| | - Yoel Geslevich
- Fertility Unit, Department of Obstetrics and Gynecology, Emek Medical Center, Afula, Israel
| | - Amir Weiss
- Fertility Unit, Department of Obstetrics and Gynecology, Emek Medical Center, Afula, Israel.,Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
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Garimella S, Karunakaran S, Gedela DR. A prospective study of oral estrogen versus transdermal estrogen (gel) for hormone replacement frozen embryo transfer cycles. Gynecol Endocrinol 2021; 37:515-518. [PMID: 32666854 DOI: 10.1080/09513590.2020.1793941] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
AIM This study was done to compare the efficacy of transdermal estrogen (gel) to oral estradiol in hormone replacement frozen embryo transfer cycles (HR- FET). MATERIALS AND METHODS This was a prospective study conducted between March 2019 and December 2019. We included 294 HR FET cycles: 156 cycles using oral estrogen tablets (oral group) and 138 cycles using transdermal gel (17 beta estradiol 0.06% w/w) (gel group). Primary objective of this study was to compare endometrial thickness (ET) on the day of progesterone start between the two groups. Our secondary objective was to compare implantation rates (IR), clinical pregnancy rates (CPR), miscarriage rates (MR), duration of estrogen administration, estradiol (E2) levels before the start of progesterone, cycle cancellation rates, patient satisfaction score and undesirable side effects between both the groups. RESULTS There was no significant difference in the ET, IR, CPR, MR and duration of E2 administration and cycle cancellation rates between both the groups. Patient satisfaction score was significantly higher (8.02 ± 1.07 vs 6.96 ± 0.99 p < .01) and side effects were significantly lower (18.1% vs 55.1%, p≤.01), in the gel group compared to the oral group. CONCLUSION This study concluded that transdermal estrogen (gel) is equally efficacious as oral estrogen in HR FET cycles with transdermal gel having an added benefit of better patient comfort with less side effects and better safety profile.
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Alyasin A, Agha-Hosseini M, Kabirinasab M, Saeidi H, Nashtaei MS. Serum progesterone levels greater than 32.5 ng/ml on the day of embryo transfer are associated with lower live birth rate after artificial endometrial preparation: a prospective study. Reprod Biol Endocrinol 2021; 19:24. [PMID: 33602270 PMCID: PMC7890906 DOI: 10.1186/s12958-021-00703-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Accepted: 01/28/2021] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Previous observational studies have highlighted the negative effects of serum hormone levels at the minimum threshold during frozen embryo transfer (FET) cycles. However, still the questions regarding the maximum threshold level, and the highest allowed dosage of hormonal medications remain unresolved. The present study was conducted to determine whether there is any relationship between the serum progesterone and estradiol levels on the day of ET, and live birth rate (LBR) in patients receiving HRT in FET cycles. METHODS In this prospective cohort study, eligible women who were undergoing their first or second FET cycles with the top graded blastocyst stage embryos were included. All patients received the same HRT regimen. FET was scheduled 5 days after administration of the first dosage of progesterone. On the morning of ET, 4-6 h after the last dose of progesterone supplementation, the serum progesterone (P4, ng/ml) and estradiol (E2, pg/ml) levels were measured. RESULTS Amongst the 258 eligible women that were evaluated, the overall LBR was 34.1 % (88/258). The serum P4 and E2 values were divided into four quartiles. The means of women's age and BMI were similar between the four quartiles groups. Regarding both P4 and E2 values, it was found that the LBR was significantly lower in the highest quartile group (Q4) compared with the others, (P = 0.002 and P = 0.042, respectively). The analysis of the multivariable logistic regression showed that the serum level of P4 on ET day, was the only significant predictive variable for LBR. The ROC curve revealed a significant predictive value of serum P4 levels on the day of ET for LBR, with an AUC = 0.61 (95 % CI: 0.54-0.68, P = 0.002). The optimum level of serum P4, with 70 % sensitivity and 50 %specificity for LBR, was 32.5 ng/ml. CONCLUSIONS The present study suggests that a serum P4 value at the maximum threshold on the day of FET is associated with reduced LBR following blastocyst transfer. Therefore, measuring and monitoring of P4 levels during FET cycles might be necessary. However, the results regarding the necessity for the screening of serum E2 levels before ET, are still controversial, and further prospective studies are required.
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Affiliation(s)
- Ashraf Alyasin
- Department of Infertility, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
- Department of Obstetrics and Gynecology, Shariati Hospital, Tehran University of Medical Sciences, 1411713135, Shariati Hospital, Jalal-e-Al-e-Ahmad Hwy, Tehran, Iran
| | - Marzieh Agha-Hosseini
- Department of Infertility, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
- Department of Obstetrics and Gynecology, Shariati Hospital, Tehran University of Medical Sciences, 1411713135, Shariati Hospital, Jalal-e-Al-e-Ahmad Hwy, Tehran, Iran
| | - Motahareh Kabirinasab
- Department of Infertility, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
- Department of Obstetrics and Gynecology, Shariati Hospital, Tehran University of Medical Sciences, 1411713135, Shariati Hospital, Jalal-e-Al-e-Ahmad Hwy, Tehran, Iran.
| | - Hojatollah Saeidi
- Department of Biology and Embryology, Omid Fertility Center, Tehran, Iran
| | - Maryam Shabani Nashtaei
- Department of Infertility, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
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Liu R, Bai S, Jiang X, Luo L, Tong X, Zheng S, Wang Y, Xu B. Multifactor Prediction of Embryo Transfer Outcomes Based on a Machine Learning Algorithm. Front Endocrinol (Lausanne) 2021; 12:745039. [PMID: 34795639 PMCID: PMC8593232 DOI: 10.3389/fendo.2021.745039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 10/15/2021] [Indexed: 11/17/2022] Open
Abstract
In vitro fertilization-embryo transfer (IVF-ET) technology make it possible for infertile couples to conceive a baby successfully. Nevertheless, IVF-ET does not guarantee success. Frozen embryo transfer (FET) is an important supplement to IVF-ET. Many factors are correlated with the outcome of FET which is unpredictable. Machine learning is a field of study that predict various outcomes by defining data attributes and using relevant data and calculation algorithms. Machine learning algorithm has been widely used in clinical research. The present study focuses on making predictions of early pregnancy outcomes in FET through clinical characters, including age, body mass index (BMI), endometrial thickness (EMT) on the day of progesterone treatment, good-quality embryo rate (GQR), and type of infertility (primary or secondary), serum estradiol level (E2) on the day of embryo transfer, and serum progesterone level (P) on the day of embryo transfer. We applied four representative machine learning algorithms, including logistic regression (LR), conditional inference tree, random forest (RF) and support vector machine (SVM) to build prediction models and identify the predictive factors. We found no significant difference among the models in the sensitivity, specificity, positive predictive rate, negative predictive rate or accuracy in predicting the pregnancy outcome of FET. For example, the positive/negative predictive rate of the SVM (gamma = 1, cost = 100, 10-fold cross validation) is 0.56 and 0.55. This approach could provide a reference for couples considering FET. The prediction accuracy of the present study is limited, which suggests that there may be some other more effective predictors to be developed in future work.
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Affiliation(s)
- Ran Liu
- Reproductive and Genetic Hospital, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Shun Bai
- Reproductive and Genetic Hospital, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Xiaohua Jiang
- Reproductive and Genetic Hospital, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Lihua Luo
- Reproductive and Genetic Hospital, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Xianhong Tong
- Reproductive and Genetic Hospital, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Shengxia Zheng
- Reproductive and Genetic Hospital, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Ying Wang
- Department of Neurosurgery, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- *Correspondence: Ying Wang, ; Bo Xu,
| | - Bo Xu
- Reproductive and Genetic Hospital, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- *Correspondence: Ying Wang, ; Bo Xu,
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Ajdary M, Keyhanfar F, Aflatoonian R, Amani A, Amjadi F, Zandieh Z, Mehdizadeh M. Design and evaluation of a novel nanodrug delivery system for reducing the side effects of clomiphene citrate on endometrium. ACTA ACUST UNITED AC 2020; 28:423-432. [PMID: 32483681 DOI: 10.1007/s40199-019-00310-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 10/23/2019] [Indexed: 01/22/2023]
Abstract
BACKGROUND Stimulation of ovulation with clomiphene citrate can cause side effects on endometrial receptivity. Formulation with nano-size may be an alternative therapy for women with ovulatory disorders. In this study, we investigated sustained-release clomiphene citrate by using Phosal-based formulation (PBF) and evaluate its decreased side effect on the endometrial receptivity. METHODS In the in-vitro study, CC loaded PBF was analyzed using Zetasizer, Fourier-transform infrared spectroscopy (FTIR), and Transmission electron microscopy (TEM). In the in-vivo study, 24 female mice were randomly divided into three groups: CC (5 mg/kg), CC/PBF (5 mg/kg) and SS (1 ml) daily administered and injected with 5 IU HCG and mated after two days. At day 4.5, pregnant mice were euthanized and endometrial tissue was extracted for quantitative polymerase chain reaction (Q-PCR) analysis. RESULTS The optimized PBF contained Phosal 50PG/glycerol in a 2:8 ratios (w/w) and the particle size of optimum formulation was 67 ± 0.30551 nm and the release of CC from CC-containing PBF was slightly faster in the first 24 h; wherein, 29% of CC was released, and 76% of CC was released up to 120 h. The mRNA levels of leukemia inhibitory factor (LIF), leukemia inhibitory factor receptor alpha (LIFR), HOXA10, Heparin-binding epidermal growth factor (HB-EGF), and epidermal growth factor (EGF) were significantly upregulated and MUC1 and PGR mRNA levels were significantly downregulated in the CC-containing PBF-treated animals compared with only CC group (P < 0.05). CONCLUSION Sustained release formulation of clomiphene citrate increased its targeting efficiency and improved the impact of the CC on implantation. Graphical abstract A new Phosal Based Formulation (PBF) was designed to decrease the side effects of Clomiphene citrate (CC) on endometrium. This drug formulation could react better during implantation by increasing the expression of genes involved in implantation. The in vivo study demonstrated that the CC-containing PBF in mice has a significantly higher endometrial receptivity, compared with the suspension.
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Affiliation(s)
- Marziyeh Ajdary
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Fariborz Keyhanfar
- Department of Pharmacology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Reza Aflatoonian
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Amir Amani
- Natural Products and Medicinal Plants Research Center, North Khorasan University of Medical Sciences, Bojnurd, Iran.,Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - FatemehSadat Amjadi
- Department of Anatomical Science, Iran University of Medical Sciences, Tehran, Iran
| | - Zahra Zandieh
- Department of Anatomical Science, Iran University of Medical Sciences, Tehran, Iran
| | - Mehdi Mehdizadeh
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran. .,Department of Anatomical Science, Iran University of Medical Sciences, Tehran, Iran.
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11
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Özdemir AZ, Karli P, Gülümser Ç. Does high estrogen level negatively affect pregnancy success in frozen embryo transfer? Arch Med Sci 2020; 18:647-651. [PMID: 35591836 PMCID: PMC9102647 DOI: 10.5114/aoms.2020.92466] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 05/15/2019] [Indexed: 11/17/2022] Open
Abstract
Introduction High estrogen levels could reduce pregnancy rates by disrupting the implantation of the embryo into the endometrium in patients treated with fresh cycles of in vitro fertilization. The aim of the present study was to investigate the effect of estrogen levels on the pregnancy and abortion rate in autologous frozen embryo transfer with hormone replacement therapy (HRT). Material and methods A historical cohort study was conducted in an academic setting to investigate the effect of estrogen levels on the pregnancy and abortion rates for all autologous artificial frozen embryo transfer cycles performed from January 2016 to January 2018. Serum estradiol levels recorded on day 2 or 3 of the cycle were stated as e1, and levels recorded on the day of progesterone were indicated as e2. Human chorionic gonadotropin (β-hCG) positivity, which was examined 14 days after the transfer, was used to evaluate biochemical pregnancy. Abortion was defined as the termination of pregnancy before the 20th gestational week. Results There were 130 patients with unexplained infertility, 20 patients with poor ovarian reserve, and 54 patients with male factor. Of the patients with unexplained infertility, poor ovarian reserve, and male factor, 58, 4, and 27 of them were pregnant, respectively. No statistically significant difference was found between the e1 and e2 levels of the pregnant and non-pregnant groups (p = 0.273, p = 0.219). In addition, there was no statistically significant difference between e2 levels in terms of the abortion rate (p = 0.722). Conclusions In autologous frozen embryo transfer with HRT, estrogen levels did not have a significant effect on the pregnancy or abortion rate. Therefore, estrogen levels do not need to be monitored in frozen embryo transfer with HRT.
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Affiliation(s)
- Ayşe Zehra Özdemir
- Faculty of Medicine, IVF Center, Ondokuz Mayıs University, Samsun, Turkey
| | - Pervin Karli
- Department of Obstetrics and Gynecology, Faculty of Medicine, Amasya University, Sabucuoğlu Şeefeddin Research Hospital, Amasya, Turkey
| | - Çağrı Gülümser
- Department of Obstetrics and Gynecology, Faculty of Medicine, Başkent University, Ankara, Turkey
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12
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Mackens S, Santos-Ribeiro S, Orinx E, De Munck N, Racca A, Roelens C, Popovic-Todorovic B, De Vos M, Tournaye H, Blockeel C. Impact of Serum Estradiol Levels Prior to Progesterone Administration in Artificially Prepared Frozen Embryo Transfer Cycles. Front Endocrinol (Lausanne) 2020; 11:255. [PMID: 32425886 PMCID: PMC7204383 DOI: 10.3389/fendo.2020.00255] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Accepted: 04/06/2020] [Indexed: 11/13/2022] Open
Abstract
Background: The need for endocrine monitoring in artificial cycles for frozen embryo transfer (FET) remains unclear and, more specifically, the value of the late-proliferative phase serum estradiol (E2) levels is with conflicting evidence in current literature. Objective: To investigate whether artificial FET cycles require endocrine monitoring for the serum E2 level prior to initiation of exogenous progesterone administration after an endometrial thickness of 6.5 mm has been reached. Design: One thousand two hundred and twenty-two (n = 1,222) artificial FETs performed in a tertiary center between 2010 and 2015 were subdivided into 3 groups according to the following late-proliferative serum E2 level percentiles: ≤p10 (E2 ≤144 pg/ml; n = 124), p11-p90 (E2 from 145 to 438 pg/ml; n = 977) and >p90 (E2 >439 pg/ml; n = 121). A mixed-effects multilevel multivariable regression analysis was performed to assess the potential effect of the late-proliferative E2 level on the live birth rate (LBR). Results: The level of late-proliferative circulating E2 showed no significant difference in terms of LBR after FET. Specifically, the multivariable regression model demonstrated a LBR of 19.5% for the p11-p90 reference group, compared to 24.4% for the ≤p10 (p = 0.251) and 19.5% for the >p90 group (p = 0.989). Conclusion: In this large retrospective dataset, no association was observed between late-proliferative phase serum E2 levels and LBR following FET in artificially prepared cycles. Although, caution is warranted due to the retrospective nature of the analysis and the potential for unmeasured confounding, we argue that monitoring of the late-proliferative serum E2 levels and using them to guide clinical decision-making (e.g., medication step-up, cycle prolongation or cancelation) may be of questionable value.
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Affiliation(s)
- Shari Mackens
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
- Research Group Reproduction and Immunology (REIM), Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | | | - Ellen Orinx
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
| | - Neelke De Munck
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
- IVI-RMA Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Annalisa Racca
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
| | - Caroline Roelens
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
| | | | - Michel De Vos
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
| | - Herman Tournaye
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
| | - Christophe Blockeel
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
- *Correspondence: Christophe Blockeel
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13
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The impact of serum oestradiol concentration prior to progesterone administration on live birth rate in single vitrified–warmed blastocyst transfer cycles. Reprod Biomed Online 2019; 39:1026-1033. [DOI: 10.1016/j.rbmo.2019.08.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 08/11/2019] [Accepted: 08/23/2019] [Indexed: 11/17/2022]
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14
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The relationship between FSH receptor polymorphism status and IVF cycle outcome: a retrospective observational study. Reprod Biomed Online 2019; 39:231-240. [PMID: 31279715 DOI: 10.1016/j.rbmo.2019.05.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 05/16/2019] [Accepted: 05/16/2019] [Indexed: 01/29/2023]
Abstract
RESEARCH QUESTION What is the association between FSH receptor (FSHR) gene polymorphism at position 680 and live birth in women undergoing IVF and intracytoplasmic sperm injection (ICSI). DESIGN In this retrospective cohort study, data were collected from the Electronic Patient Database of the VU University Medical Centre, Amsterdam, The Netherlands. Women undergoing their first IVF/ICSI cycle between January 2008 and March 2012, of whom the FSHR genotype was determined, were included. The main outcome was live birth rate. Secondary outcomes were ongoing pregnancy, total number of follicles, oocytes and embryos. RESULTS The FSHR genotype distribution was as follows: 334 women in the Asn/Asn group (28.2%), 617 in the Asn/Ser group (52.1%) and 234 in the Ser/Ser group (19.7%). Basal FSH concentration was highest in the Ser/Ser group (P = 0.006). The number of oocytes (P = 0.01) and number of embryos (P = 0.02) were lowest in the Ser/Ser group. The Asn/Asn group showed a significantly lower live birth rate. Live birth rates were 21.9% versus 31.1% and 27.6% (P = 0.009), for Asn/Asn, Asn/Ser and Ser/Ser, respectively. Logistic regression analysis, however, showed no significant difference on cumulative live birth rate between the three genotypes either unadjusted or when adjusted for age. CONCLUSION The homozygous Ser/Ser genotype of FSHR polymorphism at position 680 is associated with a reduced ovarian response to ovarian stimulation in IVF/ICSI. No difference in cumulative live birth rate was found.
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15
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Cédrin-Durnerin I, Isnard T, Mahdjoub S, Sonigo C, Seroka A, Comtet M, Herbemont C, Sifer C, Grynberg M. Serum progesterone concentration and live birth rate in frozen–thawed embryo transfers with hormonally prepared endometrium. Reprod Biomed Online 2019; 38:472-480. [DOI: 10.1016/j.rbmo.2018.11.026] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Revised: 11/14/2018] [Accepted: 11/20/2018] [Indexed: 10/27/2022]
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16
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Ferrer-Molina P, Calatayud-Lliso C, Carreras-Collado R, Muñoz-García M, Díaz-Bachiller M, Blanes-Espí J, Checa M. Oral versus transdermal oestrogen delivery for endometrial preparation before embryo transfer: a prospective, comparative, randomized clinical trial. Reprod Biomed Online 2018; 37:693-702. [PMID: 30340939 DOI: 10.1016/j.rbmo.2018.09.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Revised: 08/30/2018] [Accepted: 09/04/2018] [Indexed: 01/10/2023]
Abstract
RESEARCH QUESTION To determine whether the transdermal route is equal or superior to the oral route, when preparing the endometrium with oestrogens for embryo transfer. DESIGN Prospective, randomized controlled trial; 140 patients randomized; the pills group followed a protocol with oestradiol valerate pills and the patches group followed a protocol with oestradiol hemihydrate patches. The primary variable was endometrial thickness on day 10 ± 1 of treatment. Secondary variables were endometrial thickness on day 15 ± 1 of treatment, patient satisfaction, plasma levels of oestradiol, rates of pregnancy, miscarriage and delivery. Endometrial thickness was measured on day 10 ± 1 of the cycle, if the lining was 7 mm or less in thickness, another measurement was made on day 15 ± 1. Blood oestradiol levels were analysed on the day the endometrial lining was greater than 7 mm (day 10 ± 1 or day 15 ± 1). Patients completed a survey to evaluate comfort and side-effects. RESULTS The patches group achieved significantly thicker endometrium by the first check-up on day 10 ± 1 (7.6 mm versus 7.0 mm; P = 0.026), with lower blood levels of oestradiol (159.2 pg/ml versus 237.1 pg/ml; P < 0.001) when the endometrial thickness was over 7mm. The pills group considered the treatment more comfortable, with less side-effects. No significant differences in the rates of pregnancy, miscarriage or live birth were found. CONCLUSIONS Transdermal oestrogen treatment allows patients to reach a higher endometrial thickness after 10 days of treatment, with lower plasma levels of oestradiol, although it is not tolerated as well.
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Affiliation(s)
- P Ferrer-Molina
- Crea Centro Médico de Reproducción Asistida, València, Spain.
| | | | | | - M Muñoz-García
- Crea Centro Médico de Reproducción Asistida, València, Spain
| | | | - J Blanes-Espí
- Crea Centro Médico de Reproducción Asistida, València, Spain
| | - M Checa
- Hospital del Mar, Universitat Autònoma de Barcelona Barcelona, Spain
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17
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Mackens S, Santos-Ribeiro S, van de Vijver A, Racca A, Van Landuyt L, Tournaye H, Blockeel C. Frozen embryo transfer: a review on the optimal endometrial preparation and timing. Hum Reprod 2017; 32:2234-2242. [PMID: 29025055 DOI: 10.1093/humrep/dex285] [Citation(s) in RCA: 203] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Indexed: 01/24/2023] Open
Abstract
STUDY QUESTION What is the optimal endometrial preparation protocol for a frozen embryo transfer (FET)? SUMMARY ANSWER Although the optimal endometrial preparation protocol for FET needs further research and is yet to be determined, we propose a standardized timing strategy based on the current available evidence which could assist in the harmonization and comparability of clinic practice and future trials. WHAT IS KNOWN ALREADY Amid a continuous increase in the number of FET cycles, determining the optimal endometrial preparation protocol has become paramount to maximize ART success. In current daily practice, different FET preparation methods and timing strategies are used. STUDY DESIGN, SIZE, DURATION This is a review of the current literature on FET preparation methods, with special attention to the timing of the embryo transfer. PARTICIPANTS/MATERIALS, SETTING, METHODS Literature on the topic was retrieved in PubMed and references from relevant articles were investigated until June 2017. MAIN RESULTS AND THE ROLE OF CHANCE The number of high quality randomized controlled trials (RCTs) is scarce and, hence, the evidence for the best protocol for FET is poor. Future research should compare both the pregnancy and neonatal outcomes between HRT and true natural cycle (NC) FET. In terms of embryo transfer timing, we propose to start progesterone intake on the theoretical day of oocyte retrieval in HRT and to perform blastocyst transfer at hCG + 7 or LH + 6 in modified or true NC, respectively. LIMITATIONS REASONS FOR CAUTION As only a few high quality RCTs on the optimal preparation for FET are available in the existing literature, no definitive conclusion for benefit of one protocol over the other can be drawn so far. WIDER IMPLICATIONS OF THE FINDINGS Caution when using HRT for FET is warranted since the rate of early pregnancy loss is alarmingly high in some reports. STUDY FUNDING/COMPETING INTEREST(S) S.M. is funded by the Research Fund of Flanders (FWO). H.T. and C.B. report grants from Merck, Goodlife, Besins and Abbott during the conduct of the study. TRIAL REGISTRATION NUMBER Not applicable.
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Affiliation(s)
- S Mackens
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090 Brussels, Belgium
| | - S Santos-Ribeiro
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090 Brussels, Belgium.,Department of Obstetrics, Gynaecology and Reproductive Medicine, Santa Maria University Hospital, Avenida Professor Egas Moniz, Lisbon 1649-035, Portugal
| | - A van de Vijver
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090 Brussels, Belgium
| | - A Racca
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090 Brussels, Belgium.,Academic Unit of Obstetrics and Gynecology, IRCCS AOU San Martino-IST, University of Genova, Largo R. Benzi 10, 16132 Genova, Italy
| | - L Van Landuyt
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090 Brussels, Belgium
| | - H Tournaye
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090 Brussels, Belgium
| | - C Blockeel
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090 Brussels, Belgium.,Department of Obstetrics and Gynaecology, School of Medicine, University of Zagreb, Petrova 13, 10000 Zagreb, Croatia
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