Predictors of success after in vitro fertilization.

The last few decades have witnessed a rise in the global uptake of in vitro fertilization (IVF) treatment. To ensure optimal use of this technology, it is important for patients and clinicians to have access to tools that can provide accurate estimates of treatment success and understand the contribution of key clinical and laboratory parameters that influence the chance of conception after IVF treatment. The focus of this review was to identify key predictors of IVF treatment success and assess their impact in terms of live birth rates. We have identified 11 predictors that consistently feature in currently available prediction models, including age, duration of infertility, ethnicity, body mass index, antral follicle count, previous pregnancy history, cause of infertility, sperm parameters, number of oocytes collected, morphology of transferred embryos, and day of embryo transfer.

Prophecy, prediction, and prognosis - can we improve the advice we give on the chance of pregnancy and treatment options for infertility?

Giving patients an accurate prognosis of their chances of achieving pregnancy is difficult with our current knowledge and technology. We need new approaches and thinking to provide truthful information.

Evaluating prognosis in unexplained infertility.

IMPORTANCE: The diagnosis of unexplained infertility presents a dilemma as it signifies both uncertainty about the cause of infertility and the potential for natural conception. Immediate treatment of all would result in overtreatment. Prediction models estimating the likelihood of natural conception and subsequent live birth can guide treatment decisions. OBJECTIVE: To evaluate if in couples with unexplained infertility, prediction models are effective in guiding treatment decisions. EVIDENCE REVIEW: This review examines 25 studies that assess prediction models for natural conception in couples with unexplained infertility in terms of derivation, validation, and impact analysis. FINDINGS: The largest prediction models have been integrated in the synthesis models of Hunault, which includes female age and infertility duration, having been pregnant before and motile sperm percentage. Despite its limited discriminative capacity, this model demonstrates excellent calibration. Importantly, the impact of the Hunault model has been evaluated in randomized clinical trials, and shows that in couples with unexplained infertility and 12-month natural conception chances exceeding 30%, immediate treatment with intrauterine insemination (IUI) and controlled ovarian hyperstimulation is not better than expectant management for 6 months. Below the threshold of 30%, treatment with IUI is superior over expectant management, but immediate in vitro fertilization was not better than IUI. CONCLUSION: In couples with unexplained infertility and a good prognosis for natural conception, treatment can be delayed, whereas in couples with a poor prognosis, immediate treatment (with IUI-controlled ovarian hyperstimulation) is warranted. RELEVANCE: These data indicate that in couples with unexplained infertility, integration of prediction models into clinical decision making can optimize treatment selection and maximize fertility outcomes while limiting unnecessary treatment.

How to minimize the dropout and crossover in an infertility trial?

Randomized controlled trials and intent-to-treat analyses are important for infertility clinical studies. Dropouts or crossovers during the study process will disrupt the randomization design and affect the intent-to-treat analysis. In this review, we have briefly introduced the occurrence of dropout and crossover from our previous Reproductive Medicine Network and other related studies and provided some experience obtained from these studies on how to minimize and reduce the occurrence of dropout and crossover for infertility randomized clinical studies.

Intravaginal exposure to seminal plasma after ovum pick-up does not increase live birth rates after in vitro fertilization or intracytoplasmic sperm injection treatment: a double-blind, placebo-controlled randomized trial.

OBJECTIVE: To detect whether intravaginal exposure to prepared seminal plasma led to an absolute increase in live birth rate (LBR) after in vitro fertilization (IVF) by 10% compared with placebo. It has been suggested that intravaginal deposition of seminal plasma after ovum pick-up (OPU) for IVF treatment, increases pregnancy and LBRs. DESIGN: Double-blind, placebo-controlled prospective study. An outcome assessment was made before the type of intervention was unblinded. The outcome data were analyzed according to an intention-to-treat protocol. SETTING: University Hospital. PATIENTS: Couples scheduled for an IVF treatment cycle: in total, 792 couples (393 in the seminal plasma group and 399 in the control group) were recruited over a 5-year period of inclusion in a single-center setting. INTERVENTION: On the day of OPU, the couples were randomized into groups receiving either vaginal deposition of prepared seminal plasma from the partner or saline. Both participants and the physician were blind to the grouping. MAIN OUTCOME MEASURES: The primary outcome was a live birth (LB). The secondary outcomes were a positive pregnancy test, defined as human chorionic gonadotropin identified in urine 3 weeks after OPU , and clinical pregnancy, defined as an intrauterine viable pregnancy assessed using transvaginal sonography after 5-7 weeks. RESULTS: In the index group, 35.4% had a positive pregnancy test (relative risk [RR],0.93; 95% confidence interval {CI} 0.78-1.10), 28.8% had a clinical pregnancy (RR 1.00, 95% CI 0.97-1.03), and 26.5% had a LB (RR 0.86; 95% CI 0.70-1.07), adjusted for day of transfer, female age, and number of fertilized oocytes. Corresponding rates in the control group were 37.3%, 33.6%, and 29.8%. No statistically significant differences regarding outcomes between the two intervention groups were found. CONCLUSION: Prepared seminal plasma applied in the vagina directly after OPU did not increase the rates of LB or clinical pregnancies. The importance of immunological factors to allow the implantation of an embryo is not questioned, but no improvement in the LBRs in IVF treatment by introducing the male partner's prepared seminal plasma after OPU could be found. CLINICAL TRIAL REGISTRATION NUMBER: Clinicaltrials.gov, ID NCT02716753. Registration date 17 March, 2016, first enrollment November, 2016, completed March, 2023.

The effect of laser-assisted hatching on vitrified/warmed blastocysts: the ALADDIN randomized controlled trial.

OBJECTIVE: To evaluate whether laser-mediated assisted hatching (AH) performed on vitrified/warmed blastocysts before embryo transfer can improve live birth rate. DESIGN: The "pArtiaL zonA pelluciDa removal by assisteD hatchINg of blastocysts (ALADDIN)" is a 2-center comparative study with a parallel randomized controlled design. SETTING: University hospital. PATIENTS: Participants were recruited between September 2018 and November 2021. They were aged 18-39 years, underwent nondonor in vitro fertilization cycles, and were scheduled for elective single embryo transfer with vitrified/warmed blastocysts. Those with uterine abnormalities, body mass index of >35 kg/m2, severe male factor infertility, or performing preimplantation genetic testing were excluded. INTERVENTION: Assisted hatching was performed using a 1,480 nm diode laser, removing approximately one-third of the zona pellucida with continuous 0.2 ms pulses applied from the 1-5 o'clock positions. MAIN OUTCOME MEASURES: The primary outcome was the live birth rate. Secondary end points included clinical pregnancy, miscarriage, multiple pregnancies, preterm births, obstetric and neonatal complications, and congenital anomalies. RESULTS: Overall, 698 participants met the inclusion criteria and were randomized: 352 patients were assigned to the AH arm and 346 to the control arm. Of the participants, 105 (29.8%) and 101 (29.2%), respectively, achieved a live birth after treatment. The relative risk of live birth in patients with vitrified/warmed blastocysts treated with AH was 1.02 (95% confidence interval, 0.86-1.19). Exploratory subgroup analyses for women's age, recruiting centers, indications for in vitro fertilization, method of insemination, blastocyst quality, and days of blastocyst development failed to highlight any clinical situation that could benefit from AH in thawed blastocysts. CONCLUSION: In patients undergoing frozen embryo transfer with vitrified/warmed blastocysts, laser AH does not improve the live birth rate. Further studies are required to rule out milder but potentially interesting benefits in specific subgroups of patients. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03623659.

The impact of microfluidics sperm processing on blastocyst euploidy rates compared with density gradient centrifugation: a sibling oocyte double-blinded prospective randomized clinical trial.

OBJECTIVE: To compare the euploidy rates among blastocysts created from sibling oocytes injected with sperm and processed using microfluidics or density gradient centrifugation. DESIGN: Sibling oocyte randomized controlled trial. SETTING: Single university-affiliated infertility practice. PATIENTS: A total of 106 patients aged 18-42 years undergoing fresh in vitro fertilization treatment cycles with preimplantation genetic testing between January 2021 and April 2022 contributed 1,442 mature oocytes, which were injected with sperm and processed using microfluidics or density gradient centrifugation. INTERVENTION(S): The sperm sample is divided and processed using a microfluidics device and density gradient centrifugation for injection into sibling oocytes. MAIN OUTCOME MEASURE(S): The primary outcome was the embryo euploidy rate. Secondary outcomes included fertilization, high-quality blastulation, and ongoing pregnancy rates. RESULT(S): The blastocyst euploidy rate per mature oocyte was not significantly different in the study group compared with the control group (22.9% vs. 20.5%). The blastocyst euploidy rate per biopsied embryo was also similar between the 2 groups (53.0% vs. 45.7%). However, the fertilization rate per mature oocyte injected was found to be significantly higher in the study group compared with the control group (76.0% vs. 69.9%). The high-quality blastulation rate per mature oocyte injected was similar between the 2 groups, as was the total number of embryos frozen. There were no differences in the number of participants with no blastocysts for biopsy or the number of participants with no euploid embryos between the 2 groups. Among the male factor infertility and recurrent pregnancy loss subgroups, there were no differences in euploidy rates, fertilization rates, blastulation rates, or total numbers of blastocysts frozen, although the study was underpowered to detect these differences. Seventy-seven patients underwent frozen embryo transfer; there were no significant differences in pregnancy outcomes between the 2 groups. CONCLUSION(S): Microfluidics processing did not improve embryo euploidy rates compared with density gradient centrifugation in this sibling oocyte study, although fertilization rates were significantly higher. CLINICAL TRIAL REGISTRATION NUMBER: NCT04744025.

Assessment of clinical pregnancies in up to eight ovarian stimulation with intrauterine insemination treatment cycles in those unable to proceed with in vitro fertilization.

OBJECTIVE: To study the primary objective of clinical pregnancy (CP) rate per ovarian stimulation with intrauterine insemination (OS-IUI) treatment cycle in patients with repetitive cycles up to a maximum of 8 cycles. DESIGN: Retrospective cohort. SETTING: Large fertility clinic. PATIENTS: A total of 37,565 consecutive OS-IUI cycles from 18,509 patients were included in this study. INTERVENTIONS: Those with anovulatory diagnoses, tubal factor infertility, male factor infertility, using donor sperm, canceled cycles, and those with missing data for either baseline characteristics or outcome were excluded. The CP rate was analyzed using generalized estimating equations and controlled for age, stimulation protocol, and body mass index. MAIN OUTCOMES MEASURES: Clinical pregnancy was defined as intrauterine gestation with fetal heartbeat visible on ultrasound. RESULTS: A total of 37,565 consecutive OS-IUI cycles from 2002 through 2019 at a private practice facility were evaluated. All cycles met inclusion criteria and were used in generalized estimating equation modeling. Patients aged <35 years comprised 47.6% of the cohort. After adjustment for confounders, the mean predicted probability of CP for cycles one to 8 was 15.7% per cycle. The mean predicted probability of CP in aggregated data from cycles 2 to 4 was only 1.7% lower compared with cycle 1 as the referent (16.7% vs. 15.0%, 95% confidence interval [CI] 2nd: 0.88 {0.82, 0.95}, 3rd: 0.86 {0.79, 0.93}, 4th: 0.88 {0.79, 0.98}). However, the 15.0% mean predicted probability of CP for the second through the fourth cycle was concordant with the mean for all included cycles (15.7%). The mean predicted probability of CP of cycles 5 to 8 was not significantly different compared with the referent (16.7% vs. 16.1%, 95% CI 5th: 0.97 [0.85, 1.11], 6th: 0.93 [0.79, 1.10], 7th: 1.01 [0.81, 1.26], 8th: 1.01 [0.76, 1.34]). The modeling of consecutive cycles suggested that the adjusted cumulative predicted probability of CP from OS-IUI continues to increase with each of the 8 successive cycles. CONCLUSION: Clinical pregnancy rates are satisfactory in up to 8 consecutive OS-IUI treatment cycles. These data are useful for counseling, especially in those patients for whom in vitro fertilization is not financially or ethically feasible.

Diagnostic or prognostic? Decoding the role of embryo selection on in vitro fertilization treatment outcomes.

In this review, we take a fresh look at embryo assessment and selection methods from the perspective of diagnosis and prognosis. On the basis of a systematic search in the literature, we examined the evidence on the prognostic value of different embryo assessment methods, including morphological assessment, blastocyst culture, time-lapse imaging, artificial intelligence, and preimplantation genetic testing for aneuploidy.

Association of duration of embryo culture with risk of large for gestational age delivery in cryopreserved embryo transfer cycles.

OBJECTIVE: To examine the relationship between the day of embryo cryopreservation and large for gestational age (LGA) infants in women undergoing frozen embryo transfers (FETs) after cryopreservation on days 2-7 after fertilization and to compare the risk of the day of embryo cryopreservation to other possible risk factors of LGA after FET cycles. DESIGN: Retrospective cohort study. SETTING: Society of Assisted Reproduction Clinical Outcomes Reporting System. PATIENTS: Women undergoing FET cycles. INTERVENTION: Day of cryopreservation. MAIN OUTCOME MEASURE: Singleton LGA infant. RESULTS: A total of 33,030 (18.2%) FET cycles in the study group (n = 181,592) resulted in LGA infants during the study period of 2014-2019. There was an increase in LGA risk when cryopreservation was performed from day 2 (13.7%) to days 3-7 (14.4%, 15.0%, 18.2%, 18.5%, and 18.9%). In the log-binomial model, the risk increased compared with days 2-3 combined when cryopreservation was performed on days 5-7 (adjusted relative risk [aRR] 1.32, 95% confidence interval [CI] 1.22-1.44 for day 5, aRR 1.34, 95% CI 1.23-1.46 for day 6, and aRR 1.42, 95% CI 1.25-1.61 for day 7). Other factors most associated with LGA risk in the log-binomial model were preterm parity of >3 compared with 0 (aRR 1.82, 95% CI 1.24-2.69) and body mass index (BMI) of >35 kg/m2 compared with normal weight (aRR 1.94, 95% CI 1.88-2.01). Increasing gravity, parity, BMI, number of oocytes, and embryo grade were also associated with LGA in this model. Asian, Black, Hispanic, and combined Hawaiian and Pacific Islander were protective factors in the model compared with White patients. Low BMI (<18.5 kg/m2) was also considered a protective factor in the model compared with normal BMI. CONCLUSION: Duration of embryo culture was associated with an increased risk of LGA in this study cohort when controlling for known confounders such as maternal BMI and parity. This study sheds new light on the possible link between FET and LGA infants.