RESEARCH QUESTION:Are cumulative live birth rates similar following a freeze-all strategy compared with a fresh transfer strategy including all subsequent vitrified-warmed cycles from the same oocyte retrieval? DESIGN:The study related to the secondary outcome in a multicentre randomized controlled trial including 460 women allocated in a 1:1 ratio to: (i) a freeze-all strategy including a gonadotrophin-releasing hormone agonist trigger and single vitrified-warmed blastocyst transfer in a subsequent modified-natural frozen-thawed embryo transfer (FET) cycle; or (ii) a fresh transfer strategy with a human chorionic gonadotrophin trigger and single blastocyst in the fresh cycle. Women were recruited over a 2-year period from May 2016 to September 2018. The minimum follow-up time from the start of ovarian stimulation was 2 years. RESULTS:Baseline and treatment-related characteristics were similar between the two groups, and an equal number of participants had an additional FET following the initial fresh or frozen transfer in the two groups. Combining all FET from the included oocyte retrievals, the cumulative live birth rate was 42.6% (95/223) in the freeze-all group versus 41.7% (96/230) in the fresh strategy group (risk ratio 1.0, 95% CI 0.87-1.19; P = 0.93). The median time (interquartile range) to the first pregnancy was 106.0 (80.5-156.5) versus 29.0 (27.0-113.5) days in the freeze-all and fresh transfer group, respectively. The total number of deliveries from all subsequent FET cycles was similar between the freeze-all strategy and fresh transfer strategy group: 15.2% (34/223) versus 12.6% (29/230), respectively (P = 0.5). CONCLUSIONS:When comparing a freeze-all strategy with a fresh transfer strategy in a randomized controlled trial setting, no significant difference was found in the cumulative live birth rates between the two strategies.

Research questionAre serum progesterone levels on the day of modified natural cycle (mNC) frozen blastocyst transfer (FET) without luteal phase support (LPS) associated with clinical pregnancy rate (CPR)?DesignData was collected between January 2019 and October 2022 as a sub-study of an ongoing randomised controlled trial (RCT) assessing pregnancy outcomes in mNC-FET. The sub-study included all women (N=209) randomized to mNC-FET without LPS at the time of data extraction. Participants were aged 18-41 years, had regular menstrual cycles, and underwent mNC-FET treatment with single blastocyst transfer. Associations between serum progesterone level on day of blastocyst transfer and CPR, pregnancy rate (PR), and pregnancy loss rate (PLR) was examined between groups with low and higher progesterone levels using the 25th and the 10th percentiles as cut-offs. Multivariate logistic regression analyses were performed to adjust for potential confounding factors.ResultsProgesterone levels on the day of blastocyst transfer in mNC-FET without LPS ranged from 4.9-91.8 nmol/L, with the 25th and 10th percentile at 29.0 nmol/L and 22.5 nmol/L, respectively. Serum levels of progesterone did not differ between women with or without a clinical pregnancy (mean (SD): 38.5 (14.0) vs 36.8 (12.4) nmol/L, p=0.350). Further, the CPR, PR and PLR were similar in women with low or high progesterone levels when using the 25th or the 10th progesterone percentile as cut-off. Multivariate regression analyses showed no association between progesterone levels and CPR.ConclusionWe found no association between progesterone levels on the day of blastocyst transfer and pregnancy outcome in women undergoing mNC-FET without progesterone LPS.

RESEARCH QUESTION Are the cumulative live birth rates following a freeze-all strategy compared with a fresh transfer strategy including all subsequent frozen-thaw cycles from the same oocyte retrieval similar? DESIGN Secondary outcome in a multicentre randomised controlled trial including 460 women allocated in a 1:1 ratio to (1)Freeze-all strategy including GnRH agonist trigger and single vitrified-warmed blastocyst transfer in a subsequent modified-natural FET cycle or (2)Fresh transfer strategy with hCG trigger and single blastocyst in the fresh cycle. Women were recruited over a 2-year period from May 2016 to September 2018. The minimum follow-up time from the start of ovarian stimulation was 2 years. RESULTS Baseline and treatment-related characteristics were similar between the two groups and equal number of patients had additional frozen-thawed embryo transfers following the initial fresh or frozen transfer in the two groups. Combining all fresh and frozen transfers from the included oocyte retrieval, the cumulative live birth rate was 42.6% (95/223) in the Freeze-all group versus 41.7% (96/230) in the Fresh strategy group (risk ratio (RR): 1.0;95% CI: 0.87-1.19, P=0.93). The mean time to the first pregnancy was 125.8±60.8 versus 82.74 ± 85.9 days in the Freeze all and Fresh transfer group, respectively. The total number of deliveries from all subsequent FET cycles was similar between the freeze all strategy and fresh transfer strategy group, respectively: 15.2%(34/223) versus 12.6%(29/239), p=0.5. CONCLUSIONS When comparing a freeze-all strategy with a fresh transfer strategy we find no significant difference in cumulative live birth rates between the two strategies in a randomised controlled trial setting.

Abstract Study question Is the cumulative live birth rate (CLBR) after ICSI superior to conventional IVF (c-IVF) in first cycle fertility patients without severe male factor infertility? Summary answer In couples without severe male factor infertility, ICSI does not improve the CLBR compared to c-IVF after transfer of embryos from the first oocyte collection What is known already The ICSI procedure, originally developed for addressing severe male factor infertility, has seen expanded utilisation across various causes of infertility. Large retrospective studies and a recent randomised controlled trial (RCT) demonstrated comparable reproductive outcomes between ICSI and c-IVF in couples without male factor infertility. In approximately half of infertility cases, a male factor is involved, with about one-third attributed to male factor alone. Despite this, ICSI currently constitutes two-thirds of all assisted reproductive technology treatments worldwide Study design, size, duration Open-label, two-armed, multicentre RCT. A sample size of 784 women was required to detect a clinically relevant change of 10 percentage points with 80% power. Accounting for an expected 5% exclusion rate (dropouts and unexpected severely decreased quality sperm samples on the day of oocyte retrieval), 824 women were recruited from six public fertility clinics in Denmark between Nov 29, 2019, and Dec 14, 2022 Participants/materials, setting, methods Eligible participants were women aged 18-42 years and in their first treatment cycle with a partner/donor with normal or lightly to moderately decreased sperm quality. Randomisation was performed in a 1:1ratio between ICSI and c-IVF. The primary outcome was CLBR. Follow-up continued until the primary outcome was achieved or for a minimum of one year after the last participant’s inclusion.The primary outcome was assessed in an intention to treat (ITT) and a per protocol analysis Main results and the role of chance In total, 414 and 410 women were randomised to ICSI and c-IVF, respectively. Results include fresh as well as frozen-thawed embryo transfers from the first oocyte collection and are displayed as ITT. All transfers were elective single embryo transfers or single embryo transfers. The cumulative probability of achieving a live birth for couples/women undergoing ICSI was not different compared to those undergoing c-IVF (CLBR: ICSI 42.0% vs. c-IVF 46.6%, Risk ratio: 0.90, 95% CI: 0.77-1.05). The median time from inclusion to live birth did not differ between ICSI and c-IVF (309 days (IQR 268-378) vs 308 days (IQR 269-356); p = 0.12). Total fertilisation failure was seen in 4.9% of the ICSI group compared to 3.8% in the c-IVF group (Risk ratio: 1.29, 95% CI: 0.68-2.54) Limitations, reasons for caution This study was designed with 80% power to identify a 10% percentage point difference in CLBR between ICSI and c-IVF. We cannot dismiss the possibility of a smaller difference between the two methods Wider implications of the findings Our study, supported by prior research, shows that c-IVF rather than ICSI should be the first choice in initial cycles for patients without severe male factor infertility. Fertility staff should inform first cycle patients that ICSI does not increase the live birth rate for couples without severely decreased sperm quality Trial registration number NCT04128904

Abstract Study question What are the intimate hygiene practices of women in IVF treatment and do they correlate with the vaginal microbiota? Summary answer Hygiene practices, in specific douching and use of intimate soap significantly increased the risk of abnormal vaginal microbiota (AVM). What is known already The normal vaginal microbiota acts as a defense system against infection. AVM is a molecularly defined vaginal dysbiosis, resembling bacterial vaginosis (BV) and is dominated by anaerobic bacteria such as Gardnerella vaginalis. Importantly, AVM is associated with an increased risk of genital tract infections, poor IVF outcomes, early miscarriage and preterm labor. The cause of AVM is multifactorial and hygiene practices may interrupt the normal microbiota. Previous small studies suggested vaginal douching to be associated with an increased risk of AVM. Few studies have investigated the possible correlation between intimate hygiene practices, menstrual practices and the vaginal microbiota. Study design, size, duration Observational cohort study, including a total of 1421 IVF patients from four Danish fertility centers. The inclusion period was from 2017 to January 2022. Participants/materials, setting, methods Patients aged 18-42 years and undergoing their first, second or third IVF stimulation cycle were eligible for inclusion. The intimate hygiene practices in terms of type of soap, menstrual protection, douching and probiotics, were reported in a structured questionnaire including a total of 40 questions. Vaginal swabs were obtained prior to ovarian stimulation and subsequently subjected to quantitative PCR testing, targeting DNA of dysbiotic bacteria. Main results and the role of chance AVM was present in a total of 34 % (479/1421) of women, and 20% (272/1384) reported vaginal douching, which significantly correlated with AVM (p < 0.01, OR = 1.62 [1.23-2.12]). Intimate soap was used by 39 % (535/1384) of patients, which also significantly increased the risk of AVM ( P = 0.04, OR = 1.35 [1.08-1.69]). Water only was used by 36% (492/1384), and regular soap was used by 27% (374/1384). No correlation between use of water only and regular soap and AVM was detected. For menstrual protection 40% (433/1078) used pads, followed by tampons alone 25% (265/1078) or a combination 21% (230/1078), and 14 % (148/1078) used a menstrual cup. A trend for an increased risk of AVM when using tampons, OR 1.21 [0.91-1.62] was seen whereas use of a menstrual cup seemed to lower the risk of AVM, OR 0.71 [0.48-1.04] Active smoking, higher BMI, drinking >7 units per week and previous chlamydia infection significantly correlated with AVM (p = 0.01, p = 0.01, p = 0.04 and p = 0.01). Finally, 84% (1190/1421) reported gynecological symptoms such as vaginal discharge, dyspareunia and fungal infection, but only fishy odor significantly correlated with AVM (p < 0.01). Limitations, reasons for caution To the best of our knowledge, this is the largest study investigating the intimate hygiene practice and its correlation with AVM in an IVF population. As these results describe the practices of a Scandinavian IVF population, results may differ from other settings and ethnicities. Wider implications of the findings Exploration of the cause-and-effect relations between intimate hygiene practices and AVM is needed, requiring intervention-based prospective studies. This would lead to evidence-based advice on intimate hygiene practices and AVM prevention, possibly increasing live birth rates. The unexpected high prevalence of douching in a Danish IVF population needs further exploration. Trial registration number NCT03420859

The aim of the present randomised, double-blind, placebo-controlled trial was to investigate whether antibiotics and live lactobacilli would improve clinical pregnancy rates in IVF patients with abnormal vaginal microbiota (AVM) defined by high quantitative PCR loads of Fannyhessea vaginae and Gardnerella spp. IVF patients were randomised prior to embryo transfer into three parallel groups 1:1:1. Group one (CLLA) received clindamycin 300 mg ×2 daily for 7 days followed by vaginal Lactobacillus crispatus until the day of pregnancy scan, using the investigational drug LACTIN-V. Group two (CLPL) received clindamycin and placebo LACTIN-V, and finally, group three (PLPL) received an identical placebo of both drugs. A total of 1533 patients were screened, and 338 patients were randomised. The clinical pregnancy rate per embryo transfer was 42% (95%CI 32-52%), 46% (95%CI 36-56%) and 45% (95%CI 35-56%) in the CLLA, CLPL, PLPL groups respectively. Thus, treatment of AVM does not improve reproductive outcome. The EudraCT (European Union Drug Regulating Authorities Clinical Trials Database) clinical trial identifier is 2016-002385-31; first registration day 2016-07-11.

OBJECTIVES:To investigate if the amount of peritoneal fluid (PF) in the Pouch of Douglas at oocyte pick-up (OPU) or OPU + 5 days predict severe late-onset ovarian hyperstimulation syndrome (OHSS) in women undergoing ovarian stimulation for assisted reproductive technology (ART). STUDY DESIGN:A secondary analysis of a dual-centre RCT on 1050 women referred for their first ART treatment in two public fertility clinics in Denmark and randomized 1:1 to GnRH-antagonist or GnRH-agonist protocol. All women from the two arms who were examined on day of OPU and OPU + 5 days were included in this study (n = 940). The ability of PF in the pouch of Douglas to predict severe late-onset OHSS was assessed by multivariate logistic regression analyses and receiver operator characteristics (ROC) curve analyses and compared with other known predictors of OHSS. The final models were cross-validated by the leave-one-out method to assess the models' generalizability. RESULTS:A total of 28 (3%) women developed severe late-onset OHSS. PF in the pouch of Douglas measured on OPU + 5 days predicted severe late-onset OHSS. The optimal cut-off value was 17.5 mm at OPU + 5 days with a 61% sensitivity and 71% specificity (Area under the curve = 0.70 95% CI 0.61-0.80). PF on the day of OPU was not predictive of late on-set OHSS as the adjusted multivariate logistic regression analyses showed insignificant results. CONCLUSION:Although PF in the pouch of Douglas could predict late-onset severe OHSS, the low sensitivity underlines that it is not useful as a sole marker to decide whether to perform blastocyst transfer or to use a freeze-all strategy.

(Abstracted from Hum Reprod 2021;36(1):40–47) Pregnant women are at an increased risk of viral infections and increased risk of serious morbidity such as severe pneumonia, particularly during the first trimester. COVID-19 (coronavirus disease 2019) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

STUDY QUESTIONWhat are the attitudes towards different aspects of a freeze-all strategy and elective frozen embryo transfer (eFET) in comparison with fresh embryo transfer in assisted reproductive technology treatment among female and male patients before and after their first ART treatment cycle in a public health care setting?SUMMARY ANSWERDespite concerns about the delay in embryo transfer associated with eFET, nearly 60% of the participants were in favor of eFET compared with fresh embryo transfer assuming that the clinical pregnancy rate was equivalent.WHAT IS KNOWN ALREADYVitrification and blastocyst transfer have considerably improved success rates after FET with ongoing pregnancy rates in frozen cycles approaching those seen in fresh treatment cycles. Furthermore, the risk of ovarian hyperstimulation syndrome (OHSS) is essentially eliminated in FET cycles, and FET may be beneficial to the endometrial and fetal development because a hormonal environment mirroring the natural cycle is enabled. However, the freeze-all strategy is not yet implemented as standard care. One reason is the presumption of negative patient attitudes towards a freeze-all embryo strategy. So far, no data regarding patients' attitudes on a freeze-all strategy have been published.STUDY DESIGN, SIZE, DURATIONThis study was designed as a descriptive cross-sectional study including 165 fertility patients referred for their first ART treatment from December 2014 to June 2016.PARTICIPANTS/MATERIALS, SETTING, METHODSAll newly referred patients participating in a mandatory meeting before initiating ART treatment at the Fertility Clinic, Hvidovre Hospital, Copenhagen, Denmark were requested to fill in an online web-based questionnaire separately for men and women covering attitudes towards a freeze-all strategy, socio-demographic data and reproductive history. The patients were informed about both conventional fresh embryo transfer strategy and the freeze-all strategy prior to answering the questionnaire.MAIN RESULTS AND THE ROLE OF CHANCEThe total response rate was 77.1% (n = 165), and for women and men respectively 85.8 versus 66.0%. The female respondents were significantly more likely to consider the postponement of embryo transfer difficult compared to the male population (78.6 versus 35.5%; P < 0.001) and they were significantly more willing to accept a risk in treatment on own health to achieve a pregnancy than were the male respondents on their partners health (82.5 versus 96.8%; P = 0.025). However, 59.2% of the women and 59.7% of the men agreed that they would choose eFET over fresh embryo transfer if the chance of pregnancy were the same. Most of the patients furthermore agreed that the health of the mother and their baby was of highest importance. In the adjusted analyses we found no significant predictive factors for preferences towards a freeze-all strategy apart from a negative attitude towards delay of transfer in case of previous unsuccessful ART attempts.LIMITATIONS, REASONS FOR CAUTIONSelection bias cannot be excluded, as the total response rate was 77.1%. The hypothetical nature of the items may furthermore limit the validity of the results. In addition, the participants were from a single Fertility Clinic in the Capital Region of Denmark and may therefore not be representative for all fertility patients.WIDER IMPLICATIONS OF THE FINDINGSIn a clinical setting with similar pregnancy rates for eFET and fresh embryo transfer, these results indicate that patients, when given access to information on advantages and disadvantages of both fresh embryo transfer and eFET, are less prone to opt for fresh embryo transfer. This may be ground breaking for a patient-centered paradigm shift in routine ART treatment with a wider implementation of a freeze-all and eFET-strategy eliminating the risk of OHSS.STUDY FUNDING/COMPETING INTEREST(S)The Danish Council for Independent Research and Merck Serono supported the study. The study is part of the Reprounion Collaborative study, co-financed by the European Union, Interreg V ÖKS. No competing interests exist.

In assisted reproductive technology, prediction of treatment failure remains a great challenge. The development of more sensitive assays for measuring anti-Müllerian hormone (AMH) has allowed for the possibility to investigate if a lower threshold of AMH can be established predicting very limited or no response to maximal ovarian stimulation. A prospective observational multicenter study of 107 women, < 40 years of age with regular menstrual cycle and serum AMH levels ≤ 12 pmol/L, treated with 300 IU/day of HP-hMG in a GnRH-antagonist protocol. AMH was measured before treatment start using the Elecsys® AMH assay by Roche Diagnostics. The ability of AMH to predict follicular development and ovarian response was assessed by receiver operating characteristics (ROC). Furthermore, the relationship between AMH at start of stimulation and cycle outcome was investigated using multivariate logistic regression analysis. Five out of 107 cycles (4.7%) were cancelled due to lack of follicular development and 60/107 (56%) women did not reach the classical hCG criteria for ovulation induction (≥ 3 follicles of ≥17 mm). An AMH threshold of 4 pmol/L predicted failure to reach the classical hCG criteria with 89% specificity and 53% sensitivity and an area under the curve (AUC) of 0.76 (95% CI 0.66–0.85). AMH predicted cycle cancellation due to lack of follicular development, using a cut-off value of 1.5 pmol/L, with a specificity of 96% and sensitivity of 80% (AUC = 0.92, 95% CI 0.79–1.00). A single-unit increase in AMH was associated with a 29% decrease in odds of failure to reach the classical hCG criteria (OR 0.71 95% CI 0.59–0.85, p < 0.01). The lowest AMH value compatible with a live birth was 1.3 pmol/L. Among women with a limited ovarian reserve, pre-treatment serum AMH levels significantly predicted failure to reach the classical hCG triggering criteria and predicted lack of follicular development using a new sensitive assay, but AMH was not suitable for withholding fertility treatment, as even very low levels were associated with live births. Not relevant

Non-invasive prenatal testing (NIPT) for IVF treated-women is sparsely investigated but a few studies indicate a decrease in fetal fraction (FF) of cell-free DNA for this group. As FF is an important parameter for NIPT test performance, the relevance is high. The study includes patients from the “Freeze All” project at the Fertility Clinics at Hvidovre Hospital and Rigshospitalet, which is a randomised study with transfer of a fresh embryo in an exogenous stimulated cycle or a frozen thawed embryo transfer in a following natural cycle. Blood samples for NIPT analysis have been drawn from pregnant participants between 11 + 0 and 14 + 2 weeks of gestation and analysed at Hvidovre Hospitals NIPT Center. We have included 26 NIPT samples from pregnant women treated with fresh embryo transfer and 27 from pregnant women treated with frozen-thawed embryo transfer. NIPT analysis for the included patients have been compared with a control group of 238 naturally conceived pregnancies with a high-risk result from the combined first trimester screening. The FF was estimated by the SeqFF method. Primary analysis indicates that FF is significantly reduced for IVF-treated pregnant women (FF = 0.056) compared to naturally conceived pregnant women (FF = 0.072) (P = 0.0004) The significance persists through multivariate analysis (P < 0.0001). Furthermore, primary analysis indicates the reduction in FF to be more prominent for IVF patients who received a fresh embryo-transfer (FF = 0.049) compared to those who received a frozen-embryo transfer (FF = 0.063) (P = 0.037). As the study indicates a significant reduction in FF in IVF-patients, special precautions and interpretations seem to be needed for this group. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Investigating whether pre-ovulatory follicular fluid (FF) levels of selected proteins differ between women who do or do not develop severe ovarian hyperstimulation syndrome (OHSS) and evaluate whether they potentially could guide a “freeze-all” strategy.

IntroductionPrediction of pregnancy outcome after in vitro fertilization is important for patients and clinicians. Early plasma human chorionic gonadotropin (p-hCG) levels are the best known predictor of pregnancy outcome, but no studies have been restricted to single embryo transfer (SET) of Day-2 embryos. The aim of the present study was to investigate the predictive value of p-hCG measured exactly 14 days after the most commonly used Day-2 SET on pregnancy, delivery, and perinatal outcome.Material and methodsA retrospective analysis of prospectively collected data on 466 women who had p-hCG measured exactly 14 days after Day-2 SET during a randomized trial including 1050 unselected women (aged 18-40 years) undergoing their first in vitro fertilization/ intracytoplasmic sperm injection treatment.ResultsThe p-hCG predicted clinical pregnancy [area under the curve (AUC) 0.953; 95% CI 0.915-0.992] significantly better than ongoing pregnancy (AUC 0.803, 95% CI 0.717-0.890) and delivery (AUC 0.772, 95% CI 0.691-0.854). Women with p-hCG levels in the lowest quartile had significantly lower clinical pregnancy, ongoing pregnancy, and delivery rates (p < 0.001), whereas the pregnancy outcome and post-clinical pregnancy loss remained similar throughout the three highest p-hCG quartiles. The p-hCG level was related to neither birthweight nor gestational age at delivery.ConclusionsClinical pregnancy is significantly better predicted by p-hCG compared with ongoing pregnancy and delivery. Clinical pregnancy rates, ongoing pregnancy rates, and delivery rates remained similar throughout the three highest p-hCG quartiles with no trend towards the higher the better.