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1.
Reprod Biomed Online ; 49(1): 103852, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38657290

ABSTRACT

RESEARCH QUESTION: What clinical factors are associated with 'unexpected' poor or suboptimal responses to IVF ovarian stimulation per POSEIDON's criteria, and which AMH and AFC threshold values distinguish this population? DESIGN: Tri-centre retrospective cohort study (2015-2017) involving first-time IVF and ICSI cycles with conventional ovarian stimulation (≥150 IU/day of FSH). Eligibility criteria included sufficient ovarian reserve markers according to POSEIDON's classification (AMH ≥1.2 ng/ml; AFC ≥5). Ovarian response categories were poor (<4 oocytes), suboptimal (4-9 oocytes) and normal (≥9 oocytes). Primary outcomes included clinical factors associated with an unexpected poor or suboptimal response to conventional ovarian stimulation using logistic regression analyses, and the threshold values of AMH and AFC predicting increased risk of such responses using ROC curves. RESULTS: A total of 7625 patients met the inclusion criteria: 204 (9.3%) were poor and 1998 (90.7%) were suboptimal responders. Logistic regression identified significant clinical predictors for a poor or suboptimal response, including AFC, AMH, total gonadotrophin dose, gonadotrophin type and trigger type (P ≤ 0.02). The ROC curves indicated that AMH 2.87 ng/ml (AUC 0.740) and AFC 12 (AUC 0.826) were the threshold values predicting a poor or suboptimal response; AMH 2.17 ng/ml (AUC 0.741) and AFC 9 (AUC 0.835) predicted a poor response; and AMH 2.97 ng/ml (AUC 0.722) and AFC 12 (AUC 0.801) predicted a suboptimal response. CONCLUSIONS: The threshold values of AMH and AFC predicting 'unexpected' poor or suboptimal response were higher than expected. These findings have critical implications for tailoring IVF stimulation regimens and dosages.

2.
J Turk Ger Gynecol Assoc ; 25(1): 18-23, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38444322

ABSTRACT

Objective: The aim of this study was to describe characteristics and outcomes of assisted reproductive technology (ART) cycles performed in 2019 in Turkey. Material and Methods: One-hundred and sixty-five ART centers in Turkey were invited to submit data. The survey was sent to center directors via e-mail with anonymous links by Qualtrics™. The survey involved questions about their patient characteristics, clinical practices, and outcomes. Results: Forty-one (24.8%) centers responded to e-mails, and data gathered from 25 centers was included in the analyses. In 25 centers, 18,127 fresh or frozen transfers were carried out during the study period, of which 7796 (43.0%) were fresh and the rest were either frozen (45.2%) or embryo transfers (ET) with preimplantation genetic testing (PGT) (11.8%). The live birth rate per ET was as 30.6%, 40.1%, and 50.7% in fresh, frozen and PGT cycles, respectively. A single embryo was transferred in 65.3% of all transfers and singleton live births comprised 86.1% of all deliveries. For cycles with intrauterine insemination, 1407 were started in 2019, and 195 clinical pregnancies, 150 live births with 19 multiple pregnancies occurred. A total of 1513 ART cycles were initiated for foreign patients. Russia (29.6%), Germany (7.4%), Iraq (4.6%), Uzbekistan (3.1%), and Syria (1.4%) were the top five countries with most patients coming to Turkey for ART. Conclusion: The survey results are in parallel with the reports of international institutions and organizations. With repeated editions, the data collected with annual surveys can be used to inform ART practices in the coming years.

3.
J Assist Reprod Genet ; 41(3): 717-726, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38358433

ABSTRACT

PURPOSE: To determine the risk of not being a poor responder in ovarian stimulation (OS) for in vitro fertilization (IVF) when ovarian reserve markers are discordant-one falling within Poseidon's criteria normal range (e.g., anti-Müllerian hormone (AMH) ≥ 1.2 ng/mL or antral follicle count (AFC) ≥ 5), and the other in the poor ovarian reserve range. METHODS: A tri-center retrospective cohort study (2015-2017) involving women with discordant AMH and AFC values undergoing their first IVF/ICSI cycle using conventional OS (cOS, ≥ 150 IU/day of follicle-stimulating hormone). Discordant serum AMH and AFC values were defined according to Poseidon's criteria (AMH < 1.2 ng/mL and AFC ≥ 5 or AMH ≥ 1.2 ng/mL and AFC < 5). Poor ovarian response (POR) was < 4 retrieved oocytes. Receiver operating characteristic (ROC) curves were used to determine AMH and AFC cut-offs for non-POR. Logistic regression analysis evaluated factors associated with non-POR. RESULTS: Out of 8797 patients who underwent assessment with both AMH and AFC, 1172 (13.3%) exhibited discordant values. Of these, 854 (72.9%) had ≥ 4 oocytes retrieved. Within this group, 726 (85.0%) had "low" AMH values, whereas 128 (15.0%) had "low" AFCs. An AFC of 6 had 77% sensitivity and 52% specificity (AUC = 0.700), while AMH of 1.19 ng/mL had 31% sensitivity and 85% specificity (AUC = 0.492) for non-POR. AFC and the use of recombinant gonadotropins were positive predictors of non-POR. CONCLUSIONS: When serum AMH is < 1.19 ng/mL, but AFC is ≥ 6, there is a moderate likelihood of a non-POR during stimulation. Conversely, if AFC is < 5 but serum AMH is ≥ 1.19 ng/mL, the chances of non-POR are low. Among patients with discordant markers, AFC emerges as the primary predictor of oocyte yield.


Subject(s)
Ovarian Follicle , Ovarian Reserve , Humans , Female , Ovarian Follicle/chemistry , Anti-Mullerian Hormone , Retrospective Studies , Follicle Stimulating Hormone , Fertilization in Vitro , Ovulation Induction
4.
Reprod Biol Endocrinol ; 21(1): 86, 2023 Sep 18.
Article in English | MEDLINE | ID: mdl-37723581

ABSTRACT

BACKGROUND: In a true-natural cycle (t-NC), optimal progesterone (P4) output from the corpus luteum is crucial for establishing and maintaining an intrauterine pregnancy. In a previous retrospective study, low P4 levels (< 10 ng/mL) measured one day before warmed blastocyst transfer in t-NC were associated with significantly lower live-birth rates. In the current study, we aim to examine the relationship between patient, follicular-phase endocrine and ultrasonographic characteristics, and serum P4 levels one day prior to warmed blastocyst transfer in t-NC. METHOD: 178 consecutive women undergoing their first t-NC frozen embryo transfer (FET) between July 2017-August 2022 were included. Following serial ultrasonographic and endocrine monitoring, ovulation was documented by follicular collapse. Luteinized unruptured follicle (LUF) was diagnosed when there was no follicular collapse despite luteinizing-hormone surge (> 17 IU/L) and increased serum P4 (> 1.5 ng/mL). FET was scheduled on follicular collapse + 5 or LH surge + 6 in LUF cycles. Primary outcome was serum P4 on FET - 1. RESULTS: Among the 178 patients, 86% (n = 153) experienced follicular collapse, while 14% (n = 25) had LUF. On FET-1, the median serum luteal P4 level was 12.9 ng/mL (IQR: 9.3-17.2), ranging from 1.8 to 34.4 ng/mL. Linear stepwise regression revealed a negative correlation between body mass index (BMI) and LUF, and a positive correlation between follicular phase peak-E2 and peak-P4 levels with P4 levels on FET-1. The ROC curve analyses to predict < 9.3 ng/mL (< 25th percentile) P4 levels on FET-1 day showed AUC of 0.70 (95%CI 0.61-0.79) for BMI (cut-off: 23.85 kg/m2), 0.71 (95%CI 0.61-0.80) for follicular phase peak-P4 levels (cut-off: 0.87 ng/mL), and 0.68 (95%CI 0.59-0.77) for follicular phase peak-E2 levels (cut-off: 290.5 pg/mL). Combining all four independent parameters yielded an AUC of 0.80 (95%CI 0.72-0.88). The adjusted-odds ratio for having < 9.3 ng/mL P4 levels on FET-1 day for patients with LUF compared to those with follicle collapse was 4.97 (95%CI 1.66-14.94). CONCLUSION: The BMI, LUF, peak-E2, and peak-P4 levels are independent predictors of low serum P4 levels on FET-1 (< 25th percentile; <9.3 ng/ml) in t-NC FET cycles. Recognition of risk factors for low serum P4 on FET-1 may permit a personalized approach for LPS in t-NC FET to maximize reproductive outcomes.


Subject(s)
Follicular Phase , Progesterone , Pregnancy , Humans , Female , Embryo Transfer , Corpus Luteum
5.
Reprod Biomed Online ; 47(3): 103233, 2023 09.
Article in English | MEDLINE | ID: mdl-37400318

ABSTRACT

RESEARCH QUESTION: Does administration of subcutaneous (s.c.) progesterone support ongoing pregnancy rates (OPR) similar to vaginal progesterone using a rescue protocol in hormone replacement therapy frozen embryo transfer cycles? DESIGN: Retrospective cohort study. Two sequential cohorts - vaginal progesterone gel (December 2019-October 2021; n=474) and s.c. progesterone (November 2021-November 2022; n=249) -were compared. Following oestrogen priming, s.c. progesterone 25 mg twice daily (b.d.) or vaginal progesterone gel 90 mg b.d. was administered. Serum progesterone was measured 1 day prior to warmed blastocyst transfer (i.e. day 5 of progesterone administration). In patients with serum progesterone concentrations <8.75 ng/ml, additional s.c. progesterone (rescue protocol; 25 mg) was provided. RESULTS: In the vaginal progesterone gel group, 15.8% of patients had serum progesterone <8.75 ng/ml and received the rescue protocol, whereas no patients in the s.c. progesterone group received the rescue protocol. OPR, along with positive pregnancy and clinical pregnancy rates, were comparable between the s.c. progesterone group without the rescue protocol and the vaginal progesterone gel group with the rescue protocol. After the rescue protocol, the route of progesterone administration was not a significant predictor of ongoing pregnancy. The impact of different serum progesterone concentrations on reproductive outcomes was evaluated by percentile (<10th, 10-49th, 50-90th and >90th percentiles), taking the >90th percentile as the reference subgroup. In both the vaginal progesterone gel group and the s.c. progesterone group, all serum progesterone percentile subgroups had similar OPR. CONCLUSIONS: Subcutaneous progesterone 25 mg b.d. secures serum progesterone >8.75 ng/ml, whereas additional exogenous progesterone (rescue protocol) was needed in 15.8% of patients who received vaginal progesterone. The s.c. and vaginal progesterone routes, with the rescue protocol if needed, yield comparable OPR.


Subject(s)
Embryo Transfer , Progesterone , Pregnancy , Female , Humans , Retrospective Studies , Embryo Transfer/methods , Pregnancy Rate , Estrogens
7.
Fertil Steril ; 119(6): 996-1007, 2023 06.
Article in English | MEDLINE | ID: mdl-36813123

ABSTRACT

IMPORTANCE: The potential detrimental effects of fibroids on natural fecundity and in vitro fertilization (IVF) outcomes may be influenced by their size, location, and number. The impact of small noncavity-distorting intramural fibroids on reproductive outcomes in IVF is still controversial, with conflicting results. OBJECTIVE(S): To determine whether women with noncavity-distorting intramural fibroids of ≤6 cm size have lower live birth rates (LBRs) in IVF than female age-matched controls with no fibroids. DATA SOURCES: MEDLINE, Embase, Global Health, and Cochrane Library databases were searched from inception until July 1, 2022. STUDY SELECTION AND SYNTHESIS: Women undergoing IVF with noncavity-distorting intramural fibroids ≤6 cm constituted the study group (n = 520), whereas women with no fibroid formed the controls (n = 1392). Female age-matched subgroup analyses were performed to evaluate the impact of different cut-offs for size (≤6, ≤4, and ≤2 cm), location (the International Federation of Gynecology and Obstetrics [FIGO] type-3), and the number of fibroids on reproductive outcomes. Mantel-Haenszel odds ratios (ORs) with 95% confidence intervals (CIs) were used for outcome measures. All statistical analyses were performed using RevMan 5.4.1 MAIN OUTCOME MEASURE(S): The primary outcome measure was LBR. Secondary outcome measures were clinical pregnancy, implantation, and miscarriage rates. RESULT(S): After adopting the eligibility criteria, 5 studies were included in the final analysis. Women with ≤6 cm noncavity-distorting intramural fibroids had significantly lower LBRs (OR: 0.48, 95% CI: 0.36-0.65, 3 studies, I2=0; low-certainty evidence) compared with women with no fibroids. A significant reduction in LBRs was noted in ≤4 cm but not in the ≤2 cm subgroups. The FIGO type-3 fibroids of 2-6 cm size were associated with significantly lower LBRs. Owing to a lack of studies, the impact of the number of noncavity-distorting intramural fibroids (single vs. multiple) on IVF outcomes could not be assessed. CONCLUSION(S): We conclude that 2-6 cm sized noncavity-distorting intramural fibroids have a deleterious effect on LBRs in IVF. The presence of FIGO type-3 fibroids of 2-6 cm size is associated with significantly lower LBRs. Conclusive evidence from high-quality randomized controlled trials, the reference standard study design for studies of health care interventions, is needed before myomectomy might be offered in daily clinical practice to women with such small fibroids before undergoing IVF treatment.


Subject(s)
Leiomyoma , Uterine Myomectomy , Uterine Neoplasms , Pregnancy , Female , Humans , Pregnancy Rate , Leiomyoma/complications , Uterine Neoplasms/therapy , Uterine Neoplasms/complications , Fertilization in Vitro/adverse effects , Fertilization in Vitro/methods
8.
Hum Reprod ; 38(2): 225-236, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36478179

ABSTRACT

STUDY QUESTION: Do early- and mid-luteal serum progesterone (P4) levels impact ongoing pregnancy rates (OPRs) in fresh blastocyst transfer cycles using standard luteal phase support (LPS)? SUMMARY ANSWER: A drop in serum P4 level from oocyte pick-up (OPU) + 3 days to OPU + 5 days (negative ΔP4) is associated with a ∼2-fold decrease in OPRs. WHAT IS KNOWN ALREADY: In fresh embryo transfer cycles, significant inter-individual variation occurs in serum P4 levels during the luteal phase, possibly due to differences in endogenous P4 production after hCG trigger and/or differences in bioavailability of exogenously administered progesterone (P) via different routes. Although exogenous P may alleviate this drop in serum P4 in fresh transfer cycles, there is a paucity of data exploring the possible impact on reproductive outcomes of a reduction in serum P4 levels. STUDY DESIGN, SIZE, DURATION: Using a prospective cohort study design, following the initial enrollment of 558 consecutive patients, 340 fulfilled the inclusion and exclusion criteria and were included in the final analysis. The inclusion criteria were: (i) female age ≤40 years, (ii) BMI ≤35 kg/m2, (iii) retrieval of ≥3 oocytes irrespective of ovarian reserve, (iv) the use of a GnRH-agonist or GnRH-antagonist protocol with recombinant hCG triggering (6500 IU), (v) standard LPS and (vi) fresh blastocyst transfer. The exclusion criteria were: (i) triggering with GnRH-agonist or GnRH-agonist plus recombinant hCG (dual trigger), (ii) circulating P4 >1.5 ng/ml on the day of trigger and (iii) cleavage stage embryo transfer. Each patient was included only once. The primary outcome was ongoing pregnancy (OP), as defined by pregnancy ≥12 weeks of gestational age. PARTICIPANTS/MATERIALS, SETTING, METHODS: A GnRH-agonist (n = 53) or GnRH-antagonist (n = 287) protocol was used for ovarian stimulation. Vaginal progesterone gel (Crinone, 90 mg, 8%, Merck) once daily was used for LPS. Serum P4 levels were measured in all patients on five occasions: on the day of ovulation trigger, the day of OPU, OPU + 3 days, OPU + 5 days and OPU + 14 days; timing of blood sampling was standardized to be 3-5 h after the morning administration of vaginal progesterone gel. The delta P4 (ΔP4) level was calculated by subtracting the P4 level on the OPU + 3 days from the P4 level on the OPU + 5 days, resulting in either a positive or negative ΔP4. MAIN RESULTS AND THE ROLE OF CHANCE: The median P4 (min-max) on the day of triggering, day of OPU, OPU + 3 days, OPU + 5 days and OPU + 14 days were 0.83 ng/ml (0.18-1.42), 5.81 ng/ml (0.80-22.72), 80.00 ng/ml (22.91-161.05), 85.91 ng/ml (15.66-171.78) and 13.46 ng/ml (0.18-185.00), respectively. Serum P4 levels uniformly increased from the day of OPU to OPU + 3 days in all patients; however, from OPU + 3 days to OPU + 5 days, some patients had a decrease (negative ΔP4; n = 116; 34.1%), whereas others had an increase (positive ΔP4; n = 220; 64.7%), in circulating P4 levels. Although the median (min-max) P4 levels on the day of triggering, the day of OPU, and OPU + 3 days were comparable between the negative ΔP4 and positive ΔP4 groups, patients in the former group had significantly lower P4 levels on OPU + 5 days [69.67 ng/ml (15.66-150.02) versus 100.51 ng/ml (26.41-171.78); P < 0.001] and OPU + 14 days [8.28 ng/ml (0.28-157.00) versus 19.01 ng/ml (0.18-185.00), respectively; P < 0.001]. A drop in P4 level from OPU + 3 days to OPU + 5 days (negative ΔP4) was seen in approximately one-third of patients and was associated with a significantly lower OPR when compared with positive ΔP4 counterparts [33.6% versus 49.1%, odds ratio (OR); 0.53, 95% CI; 0.33-0.84; P = 0.008]; this decrease in OPR was due to lower initial pregnancy rates rather than increased overall pregnancy loss rates. For negative ΔP4 patients, the magnitude of ΔP4 was a significant predictor of OP (adjusted AUC = 0.65; 95% CI; 0.59-0.71), with an optimum threshold of -8.73 ng/ml, sensitivity and specificity were 48.7% and 79.2%, respectively. BMI (OR; 1.128, 95% CI; 1.064-1.197) was the only significant predictor of having a negative ΔP4; the higher the BMI, the higher the risk of having a negative ΔP4. Among positive ΔP4 patients, the magnitude of ΔP4 was a weak predictor of OP (AUC = 0.56, 95% CI; 0.48-0.64). Logistic regression analysis showed that blastocyst morphology (OR; 5.686, 95% CI; 1.433-22.565; P = 0.013) and ΔP4 (OR; 1.013, 95% CI; 0.1001-1.024; P = 0.031), but not the serum P4 level on OPU + 5 days, were the independent predictors of OP. LIMITATIONS, REASONS FOR CAUTION: The physiological circadian pulsatile secretion of P4 during the mid-luteal phase is a limitation; however, blood sampling was standardized to reduce the impact of timing. WIDER IMPLICATIONS OF THE FINDINGS: Two measurements (OPU + 3 days and OPU + 5 days) of serum P4 may identify those patients with a drop in P4 (approximately one-third of patients) associated with ∼2-fold lower OPRs. Rescuing these IVF cycles with additional P supplementation or adopting a blastocyst freeze-all policy should be tested in future randomized controlled trials. STUDY FUNDING/COMPETING INTEREST(S): None. S.C.E. declares receipt of unrestricted research grants from Merck and lecture fees from Merck and Med.E.A. P.H. has received unrestricted research grants from MSD and Merck, as well as honoraria for lectures from MSD, Merck, Gedeon-Richter, Theramex, and IBSA. H.Y. declares receipt of honorarium for lectures from Merck, IBSA and research grants from Merck and Ferring. The remaining authors declare that they have no conflict of interest. TRIAL REGISTRATION NUMBER: The study was registered at clinical trials.gov (NCT04128436).


Subject(s)
Fertilization in Vitro , Progesterone , Pregnancy , Female , Humans , Pregnancy Rate , Fertilization in Vitro/methods , Oocyte Retrieval , Prospective Studies , Lipopolysaccharides , Embryo Transfer , Ovulation Induction/methods , Oocytes , Gonadotropin-Releasing Hormone
9.
Reprod Biomed Online ; 45(3): 440-447, 2022 09.
Article in English | MEDLINE | ID: mdl-35725535

ABSTRACT

RESEARCH QUESTION: Does the timing of warmed blastocyst transfer in true natural cycle (tNC) differ according to six different commonly used definitions of LH surge, and do differences in timing have any impact on ongoing pregnancy rate (OPR)? DESIGN: Prospective monitoring, including repeated blood sampling and ultrasound analyses of 115 warmed blastocyst transfer cycles performed using tNC between January 2017 and October 2021. RESULTS: The reference timing of follicular collapse +5 days would be equivalent to LH surge +6 days in only 5.2-41.2% of the cycles employing the six different definitions of the LH surge. In contrast, the reference timing was equivalent to LH surge +7 days in the majority of cycles (46.1-69.5%) and less commonly to LH surge +8 days (1.8-38.3%) and +9 days (0-10.4%). For each definition of the LH surge, the OPR were comparable among the different warmed blastocyst transfer timings related to the LH surge (LH surge +6/+7/+8/+9 days). When logistic regression analysis was performed to evaluate the independent effect of variation of warmed blastocyst transfer timing (LH surge +6/+7/+8/+9 days) on OPR and taking LH surge +6 days as the reference, change in timing was not an independent predictor of OPR for any of the definitions of the LH surge. CONCLUSIONS: Employing a policy of performing warmed blastocyst transfer on follicular collapse +5 days and using six different definitions of the LH surge, vitrified-warmed embryo transfer timing is indeed equivalent to LH surge +7/+8 and even +9 days in a significant proportion of tNC with comparable reproductive outcomes.


Subject(s)
Blastocyst , Vitrification , Cryopreservation , Embryo Transfer , Female , Humans , Pregnancy , Pregnancy Rate , Prospective Studies , Retrospective Studies
10.
Best Pract Res Clin Obstet Gynaecol ; 85(Pt B): 159-187, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35725717

ABSTRACT

The Patient-Oriented Strategies Encompassing IndividualizeDOocyte Number (POSEIDON) criteria identify and classify the so-called 'low-prognosis' patients undergoing assisted reproductive technology (ART). Recent large-scale studies using real-world data (RWD) have shown that patients classified under this system have distinct reproductive outcomes. Moreover, these studies also confirm that POSEIDON patients are commonly found in fertility centers. RWD has substantiated the validity of the POSEIDON biomarkers' thresholds (antral follicle count [AFC] and/or anti-Müllerian hormone [AMH]) for patient classification. Lastly, a predictive model has been developed and validated to estimate the POSEIDON metric of success (i.e., number of oocytes needed to achieve at least one euploid blastocyst). Although more evidence is needed in this area, current insights from RWD research indicate that infertility patients can be counseled and managed more effectively under the POSEIDON scope, with potential gains for all parties involved.


Subject(s)
Anti-Mullerian Hormone , Reproductive Techniques, Assisted , Humans , Cost-Benefit Analysis , Oocytes , Reproduction , Ovulation Induction , Fertilization in Vitro
11.
Hum Reprod Update ; 28(5): 717-732, 2022 08 25.
Article in English | MEDLINE | ID: mdl-35258085

ABSTRACT

BACKGROUND: Efficient and safe embryo vitrification techniques have contributed to a marked worldwide increase in the use of elective frozen embryo transfer (FET). Pinpointing the day of ovulation, more commonly by documentation of the LH surge and less commonly by ultrasonography, is crucial for timing of FET in a true natural cycle (t-NC) to maximize the reproductive outcome. OBJECTIVE AND RATIONALE: The definition of the onset of the LH surge should be standardized in t-NC FET cycles; however, a clear definition is lacking in the available literature. The first search question concerns the definition of the onset of the LH surge in a natural cycle. The second search question relates to the duration between the onset of the LH surge and ovulation. SEARCH METHODS: We searched PubMed, Web of Science and Cochrane Library databases for two search questions from inception until 31 August 2021. 'Luteinizing hormone'[MeSH] OR 'LH' AND 'surge' terms were used to identify eligible articles to answer the first question, whereas 'Luteinizing hormone'[MeSH] OR 'LH' AND 'surge' OR 'rise' AND 'ovulation'[MeSH] OR 'follicular rupture' OR 'follicular collapse' were the terms used regarding the second question. The included publications were all written in the English language, conducted in women of reproductive age with regular ovulatory cycles and in whom serial serum or urine LH measurement was performed. For the quality and risk of bias assessment of the included studies, the Strengthening the Reporting of Observational Studies in Epidemiology and modified Newcastle Ottawa Scale were used. OUTCOMES: A total of 10 and 8 studies were included for search Questions 1 and 2, respectively. Over the years, through different studies and set-ups, testing in either serum or urine, different definitions for the onset of the LH surge have been developed without a consensus. An increase in LH level varying from 1.8- to 6-fold above the baseline LH level was used in seven studies and an increase of at least two or three standard deviations above the mean of the preceding LH measurements was used in two studies. An LH level exceeding the 30% of the amplitude (peak-baseline LH level) of the LH surge was defined as the onset day by one study. A marked inter-personal variation in the time interval between the onset of the LH surge and ovulation was seen, ranging from 22 to 56 h. When meta-analysis was performed, the mean duration in hours between the onset of the LH surge and ovulation was 33.91 (95% CI = 30.79-37.03: six studies, 187 cycles). WIDER IMPLICATIONS: The definition of the onset of the LH surge should be precisely defined in future well-designed studies employing state-of-art laboratory and ultrasonographic equipment. The window of implantation in a natural cycle is still a black box, and future research is warranted to delineate the optimal interval to time the embryo transfer in t-NC FET cycles. Randomized controlled trials employing different precise endocrine and/or ultrasonographic criteria for timing of FET in a t-NC are urgently required.


Subject(s)
Embryo Transfer , Ovulation , Cryopreservation/methods , Embryo Transfer/methods , Female , Humans , Luteinizing Hormone , Ovulation Induction/methods , Pregnancy , Pregnancy Rate , Retrospective Studies
12.
Front Endocrinol (Lausanne) ; 12: 688237, 2021.
Article in English | MEDLINE | ID: mdl-34305815

ABSTRACT

Despite the worldwide increase in frozen embryo transfer, the search for the best protocol to prime endometrium continues. Well-designed trials comparing various frozen embryo transfer protocols in terms of live birth rates, maternal, obstetric and neonatal outcome are urgently required. Currently, low-quality evidence indicates that, natural cycle, either true natural cycle or modified natural cycle, is superior to hormone replacement treatment protocol. Regarding warmed blastocyst transfer and frozen embryo transfer timing, the evidence suggests the 6th day of progesterone start, LH surge+6 day and hCG+7 day in hormone replacement treatment, true natural cycle and modified natural cycle protocols, respectively. Time corrections, due to inter-personal differences in the window of implantation or day of vitrification (day 5 or 6), should be explored further. Recently available evidence clearly indicates that, in hormone replacement treatment and natural cycles, there might be marked inter-personal variation in serum progesterone levels with an impact on reproductive outcomes, despite the use of the same dose and route of progesterone administration. The place of progesterone rescue protocols in patients with low serum progesterone levels one day prior to warmed blastocyst transfer in hormone replacement treatment and natural cycles is likely to be intensively explored in near future.


Subject(s)
Embryo Implantation , Embryo Transfer/methods , Endometrium , Pregnancy Rate , Cryopreservation , Female , Humans , Pregnancy
13.
Ther Adv Reprod Health ; 15: 26334941211024172, 2021.
Article in English | MEDLINE | ID: mdl-34263172

ABSTRACT

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

14.
Hum Reprod ; 36(8): 2157-2169, 2021 07 19.
Article in English | MEDLINE | ID: mdl-34179973

ABSTRACT

STUDY QUESTION: What is the cumulative delivery rate (CDR) per aspiration IVF/ICSI cycle in low-prognosis patients as defined by the Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number (POSEIDON) criteria? SUMMARY ANSWER: The CDR of POSEIDON patients was on average ∼50% lower than in normal responders and varied across POSEIDON groups; differences were primarily determined by female age, number of embryos obtained, number of embryo transfer (ET) cycles per patient, number of oocytes retrieved, duration of infertility, and BMI. WHAT IS KNOWN ALREADY: The POSEIDON criteria aim to underline differences related to a poor or suboptimal treatment outcome in terms of oocyte quality and quantity among patients undergoing IVF/ICSI, and thus, create more homogenous groups for the clinical management of infertility and research. POSEIDON patients are presumed to be at a higher risk of failing to achieve a live birth after IVF/ICSI treatment than normal responders with an adequate ovarian reserve. The CDR per initiated/aspiration cycle after the transfer of all fresh and frozen-thawed/warmed embryos has been suggested to be the critical endpoint that sets these groups apart. However, no multicenter study has yet substantiated the validity of the POSEIDON classification in identifying relevant subpopulations of patients with low-prognosis in IVF/ICSI treatment using real-world data. STUDY DESIGN, SIZE, DURATION: Multicenter population-based retrospective cohort study involving 9073 patients treated in three fertility clinics in Brazil, Turkey and Vietnam between 2015 and 2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were women with infertility between 22 and 42 years old in their first IVF/ICSI cycle of standard ovarian stimulation whose fresh and/or frozen embryos were transferred until delivery of a live born or until all embryos were used. Patients were retrospectively classified according to the POSEIDON criteria into four groups based on female age, antral follicle count (AFC), and the number of oocytes retrieved or into a control group of normal responders (non-POSEIDON). POSEIDON patients encompassed younger (<35 years) and older (35 years or above) women with an AFC ≥5 and an unexpected poor (<4 retrieved oocytes) or suboptimal (4-9 retrieved oocytes) response to stimulation, and respective younger and older counterparts with an impaired ovarian reserve (i.e. expected poor responders; AFC <5). Non-POSEIDON patients were those with AFC ≥5 and >9 oocytes retrieved. CDR was computed per one aspirated cycle. Logistic regression analysis was carried out to examine the association between patient classification and CDR. MAIN RESULTS AND ROLE OF CHANCE: The CDR was lower in the POSEIDON patients than in the non-POSEIDON patients (33.7% vs 50.6%; P < 0.001) and differed across POSEIDON groups (younger unexpected poor responder [Group 1a; n = 212]: 27.8%, younger unexpected suboptimal responder [Group 1b; n = 1785]: 47.8%, older unexpected poor responder [Group 2a; n = 293]: 14.0%, older unexpected suboptimal responder [Group 2b; n = 1275]: 30.5%, younger expected poor responder [Group 3; n = 245]: 29.4%, and older expected poor responder [Group 4; n = 623]: 12.5%. Among unexpected suboptimal/poor responders (POSEIDON Groups 1 and 2), the CDR was twice as high in suboptimal responders (4-9 oocytes retrieved) as in poor responders (<4 oocytes) (P = 0.0004). Logistic regression analysis revealed that the POSEIDON grouping, number of embryos obtained, number of ET cycles per patient, number of oocytes collected, female age, duration of infertility and BMI were relevant predictors for CDR (P < 0.001). LIMITATIONS, REASONS FOR CAUTION: Our study relied on the antral follicle count as the biomarker used for patient classification. Ovarian stimulation protocols varied across study centers, potentially affecting patient classification. WIDER IMPLICATIONS OF THE FINDINGS: POSEIDON patients exhibit lower CDR per aspirated IVF/ICSI cycle than normal responders; the differences are mainly determined by female age and number of oocytes retrieved, thereby reflecting the importance of oocyte quality and quantity. Our data substantiate the validity of the POSEIDON criteria in identifying relevant subpopulations of patients with low-prognosis in IVF/ICSI treatment. Efforts in terms of early diagnosis, prevention, and identification of specific interventions that might benefit POSEIDON patients are warranted. STUDY FUNDING/COMPETING INTEREST(S): Unrestricted investigator-sponsored study grant (MS200059_0013) from Merck KGaA, Darmstadt, Germany. The funder had no role in study design, data collection, analysis, decision to publish or manuscript preparation. S.C.E. declares receipt of unrestricted research grants from Merck and lecture fees from Merck and Med.E.A. H.Y. declares receipt of payment for lectures from Merck and Ferring. L.N.V. receives speaker fees and conferences from Merck, Merck Sharp and Dohme (MSD) and Ferring and research grants from MSD and Ferring. J.F.C. declares receipt of statistical services fees from ANDROFERT Clinic. T.M.H. received speaker fees and conferences from Merck, MSD and Ferring. P.H. declares receipt of unrestricted research grants from Merck, Ferring, Gedeon Richter and IBSA and lecture fees from Merck, Gedeon Richter and Med.E.A. C.A. declares receipt of unrestricted research grants from Merck and lecture fees from Merck. The remaining authors have no conflicts of interest to disclose. TRIAL REGISTRATION NUMBER: N/A.


Subject(s)
Ovulation Induction , Sperm Injections, Intracytoplasmic , Adult , Birth Rate , Embryo Transfer , Female , Fertilization in Vitro , Humans , Oocytes , Pregnancy , Pregnancy Rate , Retrospective Studies , Young Adult
15.
Reprod Biomed Online ; 43(1): 45-51, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34016521

ABSTRACT

RESEARCH QUESTION: Will luteal phase rescue with additional progesterone increase serum progesterone concentrations and improve reproductive outcomes in patients with low serum progesterone concentrations undergoing hormone replacement therapy (HRT) cycles? DESIGN: Case-control study including 40 consecutive patients with serum progesterone concentrations <8.75 ng/ml on the 5th day of progesterone supplementation who underwent rescue with a daily bolus of 25 mg s.c. progesterone, starting on the afternoon of the 5th day of progesterone administration. For every patient who underwent progesterone rescue, three patients matched by age, body mass index, number of previous attempts and number of blastocysts transferred, with serum progesterone concentration >8.75 ng/ml on the 5th day of progesterone administration served as controls (n = 120). The main outcome measure was ongoing pregnancy rate (OPR). RESULTS: Baseline demographic features and embryological data of the rescue and control groups were comparable. As expected, the mean serum progesterone concentration was lower in the rescue group on the 5th day of progesterone administration (7.84 ± 0.92 versus 15.32 ± 5.02 ng/ml; P < 0.001). Following rescue, the mean serum progesterone concentration on the day of vitrified-warmed embryo transfer (6th day of progesterone administration) was 33.43 ± 10.83 ng/ml (range 14.61-82.64 ng/ml), and the OPR of the rescue and control groups were comparable. CONCLUSIONS: In patients undergoing HRT vitrified-warmed blastocyst transfer with serum progesterone concentrations lower than 8.75 ng/ml 1 day prior to the scheduled embryo transfer (6th day of progesterone administration), additional supplementation with a 25 mg s.c. daily progesterone dose seems to rescue the cycle, resulting in OPR comparable to those of patients with serum progesterone >8.75 ng/ml.


Subject(s)
Embryo Transfer , Luteal Phase , Progesterone/administration & dosage , Progestins/administration & dosage , Adult , Case-Control Studies , Female , Hormone Replacement Therapy , Humans , Injections, Subcutaneous , Pregnancy , Pregnancy Rate , Progesterone/blood , Progestins/blood
16.
Front Endocrinol (Lausanne) ; 12: 630550, 2021.
Article in English | MEDLINE | ID: mdl-33790862

ABSTRACT

Objective: To estimate the prevalence of low-prognosis patients according to the POSEIDON criteria using real-world data. Design: Multicenter population-based cohort study. Settings: Fertility clinics in Brazil, Turkey, and Vietnam. Patients: Infertile women undergoing assisted reproductive technology using standard ovarian stimulation with exogenous gonadotropins. Interventions: None. Main outcome measures: Per-period prevalence rates of POSEIDON patients (overall, stratified by POSEIDON groups and by study center) and the effect of covariates on the probability that a patient be classified as "POSEIDON". Results: A total of 13,146 patients were included. POSEIDON patients represented 43.0% (95% confidence interval [CI] 42.0-43.7) of the studied population, and the prevalence rates varied across study centers (range: 38.6-55.7%). The overall prevalence rates by POSEIDON groups were 44.2% (group 1; 95% CI 42.6-45.9), 36.1% (group 2; 95% CI 34.6-37.7), 5.2% (group 3; 95% CI 4.5-6.0), and 14.4% (group 4; 95% CI: 13.3-15.6). In general, POSEIDON patients were older, had a higher body mass index (BMI), lower ovarian reserve markers, and a higher frequency of female factor as the primary treatment indication than non-POSEIDON patients. The former required larger doses of gonadotropin for ovarian stimulation, despite achieving a 2.5 times lower number of retrieved oocytes than non-POSEIDON patients. Logistic regression analyses revealed that female age, BMI, ovarian reserve, and a female infertility factor were relevant predictors of the POSEIDON condition. Conclusions: The estimated prevalence of POSEIDON patients in the general population undergoing ART is significant. These patients differ in clinical characteristics compared with non-POSEIDON patients. The POSEIDON condition is associated with female age, ovarian reserve, BMI, and female infertility. Efforts in terms of diagnosis, counseling, and treatment are needed to reduce the prevalence of low-prognosis patients.


Subject(s)
Fertilization in Vitro , Infertility/diagnosis , Infertility/epidemiology , Ovarian Reserve/physiology , Ovulation Induction , Reproductive Techniques, Assisted , Adult , Brazil/epidemiology , Cohort Studies , Female , Gonadotropins/blood , Humans , Prevalence , Prognosis , Retrospective Studies , Treatment Outcome , Turkey/epidemiology , Vietnam/epidemiology
17.
Hum Reprod ; 36(6): 1530-1541, 2021 05 17.
Article in English | MEDLINE | ID: mdl-33822057

ABSTRACT

STUDY QUESTION: What is the agreement between antral follicle count (AFC) and anti-Müllerian hormone (AMH) levels when used to patient classification according to the Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number (POSEIDON) criteria? SUMMARY ANSWER: Our study indicates a strong agreement between the AFC and the AMH levels in classifying POSEIDON patients; thus, either can be used for this purpose, although one in four women will have discordant values when both biomarkers are used. WHAT IS KNOWN ALREADY: According to the POSEIDON criteria, both AFC and AMH may be used to classify low-prognosis patients. Proposed AFC and AMH thresholds of 5 and 1.2 ng/ml, respectively, have their basis in published literature; however, no study has yet determined the reproducibility of patient classification in comparing one biomarker with the other, nor have their thresholds ever been validated within this patient population. STUDY DESIGN, SIZE, DURATION: A population-based cohort study involving 9484 consecutive patients treated in three fertility clinics in Brazil, Turkey and Vietnam between 2015 and 2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were infertile women between 22 and 46 years old in their first in vitro fertilization/intracytoplasmic sperm injection cycle of standard ovarian stimulation with exogenous gonadotropins whose baseline ovarian reserves had been assessed by both AFC and AMH. Details of pre- and post-treatment findings were input into a coded research file. Two indicators of interest were created to classify patients according to the POSEIDON criteria based upon AFC and AMH values. Patients who did not fit any of the four POSEIDON groups were classified as non-POSEIDON. AFC was determined in the early follicular phase using two-dimensional (2D) transvaginal ultrasonography, whereas AMH values were based on the modified Beckman Coulter generation II enzyme-linked immunosorbent assay. Agreement rates were computed between AFC and AMH to classify patients using Cohen's kappa statistics. Logistic regression analyzes were carried out to examine the association between ovarian markers and low (<4) and suboptimal (4-9) oocyte yield. MAIN RESULTS AND THE ROLE OF CHANCE: The degree of agreement in classifying patients according to POSEIDON groups was strong overall (kappa = 0.802; 95% CI: 0.792-0.811). A total of 73.8% of individuals were classified under the same group using both biomarkers. The disagreement rates were ∼26% and did not diverge when AFC or AMH was used as the primary biomarker criterion. Significant regression equations were found between ovarian markers and oocyte yield (P < 0.0001). For low oocyte yield, the optimal AFC and AMH cutoff values were 5 and 1.27 ng/ml with sensitivities of 0.61 and 0.66, specificities of 0.81 and 0.72, and AUC receiver operating characteristics of 0.791 and 0.751, respectively. For suboptimal oocyte yield respective AFC and AMH cutoffs were 12 and 2.97 ng/ml with sensitivities of 0.74 and 0.69, specificities of 0.76 and 0.66 and AUCs of 0.81 and 0.80. LIMITATIONS, REASONS FOR CAUTION: Our study relied on 2D transvaginal sonography to quantify the AFC and manual Gen II assay for AMH determination and classification of patients. AMH data must be interpreted in an assay-specific manner. Treatment protocols varied across centers potentially affecting patient classification. WIDER IMPLICATIONS OF THE FINDINGS: Three of four patients will be classified the same using either AFC or AMH values. Both biomarkers provide acceptable and equivalent accuracy in predicting oocyte yield further supporting their use and proposed thresholds in daily clinical practice for patient classification according to the POSEIDON criteria. However, the sensitivity of POSEIDON thresholds in predicting low oocyte yield is low. Clinicians should adopt the biomarker that may best reflect their clinical setting. STUDY FUNDING/COMPETING INTEREST(S): Unrestricted investigator-sponsored study grant (MS200059_0013) from Merck KGaA, Darmstadt, Germany. The funder had no role in study design, data collection, analysis, decision to publish or manuscript preparation. S.C.E. declares receipt of unrestricted research grants from Merck and lecture fees from Merck and Med.E.A. H.Y. declares receipt of payment for lectures from Merck and Ferring. L.N.V. receives speaker fees and conferences from Merck, Merck Sharp and Dohme (MSD) and Ferring and research grants from MSD and Ferring. T.M.H. received speaker fees and conferences from Merck, MSD and Ferring. The remaining authors have nothing to disclose. TRIAL REGISTRATION NUMBER: not applicable.


Subject(s)
Anti-Mullerian Hormone , Infertility, Female , Adult , Brazil , Cohort Studies , Female , Germany , Humans , Infertility, Female/diagnosis , Middle Aged , Oocytes , Ovulation Induction , Prognosis , Reproducibility of Results , Turkey , Vietnam , Young Adult
18.
Reprod Biomed Online ; 42(5): 892-900, 2021 May.
Article in English | MEDLINE | ID: mdl-33810985

ABSTRACT

RESEARCH QUESTION: To assess incidence of abnormal cleavage among biopsied blastocysts; to compare euploidy rates of the blastocysts with abnormal and normal cleavage; and to compare single euploid blastocyst transfer (SEBT) outcome derived from embryos with normal or abnormal cleavage. DESIGN: Retrospective analysis of prospectively collected data in a private IVF clinic. Consecutive 554 patients (749 cycles) undergoing preimplantation genetic testing for aneuploidy (n = 497; 671 cycles) or monogenic diseases (n = 57; 78 cycles) were included. All assessments for abnormal cleavage were carried out retrospectively; presence of abnormal cleavage was not a factor in deciding which euploid embryo to transfer. A total of 1015 blastocysts were biopsied and 295 SEBT procedures were carried out. Main outcome measure was live birth rate (LBR). RESULTS: Incidence of reverse cleavage, direct cleavage, and reverse plus direct cleavage, were 7.7%, 6.4% and 2.3%, respectively. Of the 1015 biopsied blastocysts, 35.0% were euploid. Blastocysts with abnormal cleavage, in total, had a significantly higher euploidy rate compared with blastocysts with normal cleavage (44.6% [74/166] versus 33.1% [281/849]; P = 0.017). The LBR after SEBT with normal, reverse and direct cleavage, and direct cleavage plus reverse cleavage, was 133/238 (55.9%), 6/26 (23.1%), 8/24 (33.3%) and 0/3 (0.0%) (P < 0.001). Generalized estimating equation analysis showed that the presence of abnormal cleavage pattern was the only independent predictor of LBR (OR 0.316; 95% CI 0.115 to 0.867; P = 0.013). CONCLUSIONS: Blastocysts with direct or reverse cleavage should be biopsied in preimplantation genetic testing cycles if they are morphologically eligible. Euploid blastocysts with abnormal cleavage, however, have approximately half the LBR of those euploid blastocyst with normal cleavage, hence, blastocysts with abnormal cleavage should have lower priority for transfer.


Subject(s)
Aneuploidy , Blastocyst/pathology , Embryo Transfer/statistics & numerical data , Embryonic Development , Adult , Embryo, Mammalian/abnormalities , Female , Humans , Live Birth , Pregnancy , Retrospective Studies
19.
JBRA Assist Reprod ; 24(4): 436-441, 2020 10 06.
Article in English | MEDLINE | ID: mdl-32489086

ABSTRACT

OBJECTIVE: In order to help make the dream of parenthood come true for oocyte acceptors, it is essential that the procedure is not dangerous or unpleasant for oocyte donors. The aim of this study was to identify differences in safety, efficacy and patient acceptability between a traditional stimulation antagonist protocol with recombinant-FSH (rFSH) with hCG-triggering, compared with an innovative antagonist protocol with corifollitropin alfa (Elonva®) plus GnRH agonist triggering in oocyte donors. METHODS: A prospective longitudinal study was conducted at an in vitro fertilization center in Greece. The same eighty donors underwent two consecutive antagonist stimulation schemes. Primary outcomes were patient satisfaction (scored by a questionnaire) and delivery rate per donor. Secondary outcomes were mean number of cumulus-oocyte-complexes, metaphase II (MII) oocytes and ovarian hyperstimulation syndrome (OHSS) rate. RESULTS: Donors reported better adherence and less discomfort with the corifollitropin alpha + GnRH agonist-triggering protocol (p<0.001). No significant differences were identified in the clinical pregnancy rate per donor (p=0.13), the delivery rates, the number of oocytes (p=0.35), the number of MII oocytes (p=0.50) and the number of transferred embryos, between the two protocols. However, the luteal phase duration was significantly shorter (p<0.001) in the corifollitropin alpha + GnRH agonist-triggering protocol. Moreover, three cases of moderate OHSS (3.75%) were identified after hCG triggering, whereas no case of OHSS occurred after GnRH agonist ovulation induction (p=0.25). CONCLUSION: The use of corifollitropin alpha combined with a GnRH agonist for triggering is a safe, effective and acceptable protocol for oocyte donors.


Subject(s)
Fertility Agents, Female/administration & dosage , Follicle Stimulating Hormone, Human/administration & dosage , Gonadotropin-Releasing Hormone/agonists , Oocyte Donation/methods , Oocytes/drug effects , Ovulation Induction/methods , Adult , Female , Fertility Agents, Female/adverse effects , Follicle Stimulating Hormone, Human/adverse effects , Humans , Longitudinal Studies , Pregnancy , Pregnancy Rate , Prospective Studies , Young Adult
20.
Reprod Biol Endocrinol ; 18(1): 45, 2020 May 13.
Article in English | MEDLINE | ID: mdl-32404170

ABSTRACT

The prolonged lockdown of health services providing high-complexity fertility treatments -as currently recommended by many reproductive medicine entities- is detrimental for society as a whole, and infertility patients in particular. Globally, approximately 0.3% of all infants born every year are conceived using assisted reproductive technology (ART) treatments. By contrast, the total number of COVID-19 deaths reported so far represents approximately 1.0% of the total deaths expected to occur worldwide over the first three months of the current year. It seems, therefore, that the number of infants expected to be conceived and born -but who will not be so due to the lockdown of infertility services- might be as significant as the total number of deaths attributed to the COVID-19 pandemic. We herein propose remedies that include a prognostic-stratification of more vulnerable infertility cases in order to plan a progressive restart of worldwide fertility treatments. At a time when preventing complications and limiting burdens for national health systems represent relevant issues, our viewpoint might help competent authorities and health care providers to identify patients who should be prioritized for the continuation of fertility care in a safe environment.


Subject(s)
Coronavirus Infections , Fertilization in Vitro , Infertility, Female/therapy , Pandemics , Pneumonia, Viral , Reproductive Health Services/organization & administration , Reproductive Techniques, Assisted , Betacoronavirus , COVID-19 , Coronavirus , Female , Humans , Pregnancy , SARS-CoV-2 , Sperm Injections, Intracytoplasmic
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