Frozen embryo transfer outcomes decline with increasing female body mass index in female but not male factor infertility: analysis of 56,564 euploid blastocyst transfers.

OBJECTIVE: To evaluate the association of body mass index (BMI) with cycle outcomes after euploid frozen blastocyst transfer. DESIGN: Retrospective cohort study. SETTING: Not applicable. PATIENT(S): A total of 56,564 first single autologous euploid frozen embryo transfers from the 2016-2019 Society for Assisted Reproductive Technology database were analyzed using BMI and using World Health Organization BMI cohorts. Subanalyses were performed on cycles among patients with a sole diagnosis of polycystic ovary syndrome (PCOS) (n = 4,626) and among patients with only a male factor (n = 10,854). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Clinical pregnancy, pregnancy loss, and live birth (LB). RESULT(S): Success rates and adjusted odds ratios (aORs) with 95% confidence intervals (CIs) for all outcomes were most favorable among those with normal BMI and progressively worsened with increasing BMI. These trends persisted among patients with PCOS for clinical pregnancy (aOR, 0.99; 95% CI, 0.98-0.997), pregnancy loss (aOR, 1.02; 95% CI, 1.01-1.04), and LB (aOR, 0.98; 95% CI, 0.97-0.99), but not among patients with a male factor only for clinical pregnancy (aOR, 1.00; 95% CI, 0.99-1.01), pregnancy loss (aOR, 1.01; 95% CI, 0.99-1.03), or LB (aOR, 0.99; 95% CI, 0.98-1.00). CONCLUSION(S): In the largest cohort to date, increasing BMI was associated with decreased pregnancy and LB and increased pregnancy loss after euploid frozen embryo transfers among the entire cohort and among patients with a sole diagnosis of PCOS; however, these results were attenuated among patients with a sole diagnosis of male factor infertility, suggesting that associated female infertility diagnoses and not BMI alone may underlie this trend.

Validation of prognosis-based in vitro fertilization grant selection criteria.

Objective: To validate a prognosis-based scoring system for in vitro fertilization (IVF) grant allocation. Design: Retrospective cohort study. Setting: A 501(c)(3) nonprofit foundation that awards donated IVF cycles and grants to those with demonstrated financial need. In contrast to lottery-based or subjective allocation systems, applications are scored according to medical prognostic criteria in addition to personal characteristics. Patients: Grant recipients from 2015 to 2019. Interventions: None. Main outcome measures: Live birth rate (LBR) and cumulative LBR (CLBR) among grant recipients were compared with 2019 Society for Assisted Reproductive Technology (SART) national averages. Results: A total of 435 applications were reviewed, with 59 grants awarded for 51 autologous IVF cycles, 6 donor oocyte cycles, and 2 gestational carrier cycles, resulting in 39 live births after initial embryo transfer (LBR 61.9%) and 43 CLBRs (CLBR 72.9%). Among autologous cycles, the mean (±SD=3.9 years) age was 31.8 years, and LBR and CLBR were 62.8% and 68.6% vs. 28.2% and 37.1% among all autologous SART cycles, respectively. A subanalysis of grant recipients aged <35 years (n=39) revealed LBR and CLBR of 66.7% and 74.4% vs. 40.7% and 47.8% among autologous SART cycles aged <35 years, respectively. Conclusions: A scoring system incorporating medical criteria identified IVF grant applicants with a high likelihood of achieving a LB. Although most IVF grant programs select recipients through a lottery or personal characteristics, a prognosis-based scoring system should be considered to maximize LBR in a limited resource setting.

Sex ratio of offspring is not statistically altered following pre-implantation genetic testing under a specific sex selection policy.

PURPOSE: To determine whether the use of pre-implantation genetic testing (PGT) under a specific sex selection policy is associated with alterations in offspring sex ratio. METHODS: This was a single-center retrospective cohort study of singleton live births from January 2018-December 2020 achieved via single blastocyst non-PGT or PGT frozen embryo transfer (FET). Per institutional policy, sex may be disclosed following PGT. If both sexes are available and morphologic grade is similar, patients may select the sex of the embryo to be transferred. Demographics and cycle characteristics were compared between non-PGT vs. PGT cycles with Mann-Whitney U or χ2. Poisson regression with robust variance estimates was used to model the probability of female vs. male offspring among non-PGT vs. PGT cycles, reported as risk ratio (RR) and 95% confidence interval (CI). RESULTS(S): Among 541 live births, 350 (64.7%) were achieved with PGT and 191 (35.3%) without PGT. In both groups, female sex was more common, representing 59.4% of PGT-offspring and 55.0% of non-PGT offspring. After adjusting for potential confounders, the use of PGT was not significantly associated with an increased likelihood of female offspring (RR 1.04, 95% CI 0.98-1.11, p = 0.22). CONCLUSION(S): Singletons born following FET had a higher rate of female sex than male. Allowing sex selection per institutional policy did not increase this ratio. These results contrast with those of prior publications and should motivate individual centers to monitor their own sex ratios. As utilization of PGT increases, local, regional, and national monitoring will become increasingly important.

Chronic endometritis: screening, treatment, and pregnancy outcomes in an academic fertility center.

PURPOSE: To identify the prevalence of chronic endometritis (CE), compare the efficacy of antibiotic regimens for CE, and examine pregnancy outcomes after treatment for CE among patients in an academic fertility clinic. METHODS: In this retrospective cohort study, data from patients who underwent endometrial sampling (ES) for CE evaluation at a single academic institution from 2014 to 2020 were collected and analyzed. Rates of CE were compared by indication for ES including recurrent pregnancy loss (RPL), implantation failure (IF), and recent first-trimester pregnancy loss. Treatment and pregnancy outcomes were also evaluated. RESULTS: Six hundred fifty-three individuals underwent ES to evaluate for CE. The overall prevalence of CE was 28.5%; when stratified by indication, the prevalence of CE was 66.2% for recent first-trimester loss, 27.9% for RPL, and 13.1% for IF (p < .001). Of those with CE, 91.9% received antibiotics, most commonly doxycycline (76.0%). CE clearance was not significantly different when doxycycline was compared to all other regimens (71.3% vs. 58.8%, p = .17), and 68.5% of patients cleared CE after one course of antibiotics. Following two antibiotic courses, CE was cleared in 88.3% of patients. Live birth rates (LBRs) were higher for those with cleared CE compared to patients with untreated CE (34.1% vs. 5.6%, p = .014) and similar for those with cleared CE versus those without CE (34.1% vs. 29.3%, p = .297). CONCLUSION: CE is common among patients with infertility, particularly those with a recent first-trimester loss. Treatment and clearance of CE were associated with higher LBRs; however, persistent CE was common despite treatment with antibiotics.

Childbearing, Infertility, and Career Trajectories Among Women in Medicine.

Importance: Although women are increasingly represented within medicine, gender disparities persist in time to promotion, achievement of academic rank, and appointment to leadership positions, with no narrowing of this gap over time. Career-specific fertility and family building challenges among women physicians may contribute to ongoing disparities and academic attrition. Objective: To evaluate delayed childbearing and infertility among women in medicine and investigate the extent to which women physicians may alter career trajectories to accommodate family building and parenthood. Design, Setting, and Participants: This survey study was conducted among women physicians, with surveys distributed through medical society electronic mailing lists (listserves) and social media from March to August 2022. Main Outcomes and Measures: Baseline demographic information and fertility knowledge were assessed. Descriptive data on delayed childbearing, infertility, use of assisted reproductive technology, and career alterations to accommodate parenthood were collected. Factors associated with timing of pregnancy and family building regret were assessed using Likert-type scales. Group differences in fertility knowledge, delayed childbearing, infertility, and family building regret were evaluated using χ2 analyses. Results: A total of 1056 cisgender women (mean [SD] age, 38.3 [7.7] years) were surveyed across level of training (714 attending physicians [67.6%] and 283 residents or fellows [26.8%]), specialty (408 surgical [38.6%] and 638 nonsurgical [60.4%] specialties), and practice setting (323 academic [45.2%], 263 private [24.9%], and 222 community [21.0%] settings). Among respondents, 1036 individuals [98.1%] resided in the US. Overall, 910 respondents (86.2%) were married or partnered and 690 respondents (65.3%) had children. While 824 physicians (78.0%) correctly identified the age of precipitous fertility decline, 798 individuals (75.6%) reported delaying family building and 389 individuals (36.8%) had experienced infertility. Concerning measures taken to accommodate childbearing or parenthood, 199 women (28.8%) said they had taken extended leave, 171 women (24.8%) said they had chosen a different specialty, 325 women (47.1%) said they had reduced their work hours, 171women (24.8%) said they had changed their practice setting, and 326 women (47.2%) said they had passed up opportunities for career advancement among those with children. Additionally, 30 women with children (4.3%) had left medicine entirely. Conclusions and Relevance: In this survey study, women physicians reported that career-related pressures influenced the timing of childbearing and led to marked alterations to career trajectories to accommodate family building and parenthood. These findings suggest that fertility and family building concerns among women in medicine may contribute to ongoing gender disparities and attrition and represent a potentially critical area for policy reform and future change.

Inflammatory Activity After Diverse Fertility Treatments: A Multicenter Analysis in the Modern Multiple Sclerosis Treatment Era.

BACKGROUND AND OBJECTIVES: Patients with multiple sclerosis (MS) may seek fertility treatment (FT)-including in vitro fertilization (IVF). Variable relapse risk after IVF has been reported in small historical cohorts, with more recent studies suggesting no change in annualized relapse rate (ARR). The objective of this study was to evaluate ARR 12 months pre-FT and 3 months post-FT in a multicenter cohort and identify factors associated with an increased risk of relapse. METHODS: Patients with clinically isolated syndrome (CIS) or MS aged 18-45 years with at least 1 FT from January 1, 2010, to October 14, 2021, were retrospectively identified at 4 large academic MS centers. The exposed period of 3 months after FT was compared with the unexposed period of 12 months before FT. FTs included controlled ovarian stimulation followed by fresh embryo transfer (COS-ET), COS alone, embryo transfer (ET) alone, and oral ovulation induction (OI). The Wilcoxon signed rank test and mixed Poisson regression models with random effects were used to compare ARR pre-FT vs post-FT, with the incidence rate ratio (IRR) and 95% CI reported. RESULTS: One hundred twenty-four FT cycles among 65 patients with MS (n = 56) or CIS (n = 9) were included: 61 COS-ET, 19 COS alone, 30 ET alone, and 14 OI. The mean age at FT was 36.5 ± 3.8 years, and the mean disease duration was 8.2 ± 5.0 years. Across 80 cycles with COS, only 5 relapses occurred among 4 unique patients within 3 months of treatment. The mean ARR after COS and before was not different (0.26 vs 0.25, p = 0.37), and the IRR was 0.95 (95% CI: 0.52-1.76, p = 0.88). No cycles with therapeutic disease-modifying therapies (DMTs) during COS had 3 months relapse (ARR 0 post-COS vs 0.18 pre-COS, p = 0.02, n = 34). Relapse rates did not vary by COS protocol. Among COS-ET cycles that achieved pregnancy (n = 43), ARR decreased from 0.26 to 0.09 (p = 0.04) within the first trimester of pregnancy. There were no relapses 3 months after ET alone and 1 relapse after OI. DISCUSSION: In this modern multicenter cohort of patients with MS undergoing diverse FTs, which included 43% on DMTs, we did not observe an elevated relapse risk after FT.

Natural Cycle Frozen Embryo Transfer: Evaluating Optimal Protocols for Preparation and Timing.

Background: While natural cycle frozen embryo transfer (NC-FET) is becoming increasingly common, significant practice variation exists in the use of ovulation induction medications, administration of ovulation trigger, and timing of embryo transfer without consensus as to the optimal protocol. Aims: The objective of this study is to evaluate the association of key aspects of the NC-FET protocol with implantation, pregnancy and live birth. Settings and Design: This was a retrospective cohort study of blastocyst stage NC-FET cycles from October 2019 to July 2021 at a single academic fertility centre. Materials and Methods: Protocols varied between cycles across three key parameters which were evaluated as primary predictors of cycle outcomes: (1) use of letrozole for mild ovarian stimulation/ovulation induction, (2) administration of exogenous ovulation trigger versus spontaneous luteinising hormone surge and (3) transfer timing based on ovulation trigger versus sequential progesterone monitoring. Primary outcomes included implantation rate, clinical pregnancy and ongoing pregnancy. Statistical Analysis Used: Generalised estimating equations were fitted to obtain adjusted odds ratios or rate ratios as appropriate with 95% confidence intervals for each outcome across the three primary predictors. Results: A total of 183 cycles from 170 unique patients were eligible for inclusion. The average implantation rate was 0.58, resulting in an overall clinical pregnancy and ongoing pregnancy rate of 59.0% and 51.4%, respectively. After adjusting for age at embryo freeze and history of a failed embryo transfer, there were no significant associations between any predictor and implantation rate, clinical pregnancy, ongoing pregnancy, or live birth. Conclusion: In NC-FET, a variety of preparation and timing protocols may lead to comparable cycle outcomes, potentially allowing for flexibility on the basis of patient and physician preference. These findings warrant validation in a larger, randomised trial.

A SART data cost-effectiveness analysis of planned oocyte cryopreservation versus in vitro fertilization with preimplantation genetic testing for aneuploidy considering ideal family size.

OBJECTIVE: To determine the cost-effectiveness of planned oocyte cryopreservation (OC) as a strategy for delayed childbearing to achieve 1 or 2 live births (LB) compared with in vitro fertilization (IVF) and preimplantation genetic testing for aneuploidy (PGT-A) at advanced reproductive age. DESIGN: Decision tree model with sensitivity analyses using data from the Society for Assisted Reproductive Technology Clinical Outcome Reporting System and other clinical sources. SETTING: Not applicable. PATIENT(S): A data-driven simulated cohort of patients desiring delayed childbearing with an ideal family size of 1 or 2 LB. INTERVENTION(S): Not applicable. MAIN OUTCOME MEASURE(S): Probability of achieving ≥1 or 2 LB, average and maximum cost per patient, cost per percentage point increase in chance of LB, and population-level cost/LB. RESULT(S): For those desiring 1 LB, planned OC at age 33 with warming at age 43 decreased the average total cost per patient from $62,308 to $30,333 and increased the likelihood of LB from 50% to 73% when compared with no OC with up to 3 cycles of IVF/PGT-A at age 43. For those desiring 2 LB, 2 cycles of OC at age 33 and warming at age 40 yielded the lowest cost per patient and highest likelihood of achieving 2 LB ($51,250 and 77%, respectively) when compared withpursuing only 1 cycle of OC ($75,373 and 61%, respectively), no OC and IVF/PGT-A with embryo banking ($79,728 and 48%, respectively), or no OC and IVF/PGT-A without embryo banking ($79,057 and 19%, respectively). Sensitivity analyses showed that OC remained cost-effective across a wide range of ages at cryopreservation. For 1 LB, OC achieved the highest likelihood of success when pursued before age 32 and remained more effective than IVF/PGT-A when pursued before age 39, and for 2 LB, 2 cycles of OC achieved the highest likelihood of success when pursued before age 31 and remained more effective than IVF/PGT-A when pursued before age 39. CONCLUSION(S): Among patients planning to postpone childbearing, OC is cost-effective and increases the odds of achieving 1 or 2 LB when compared with IVF/PGT-A at a more advanced reproductive age.

Knowledge of Fertility and Perspectives About Family Planning Among Female Physicians.

Importance: Pervasive gender disparities exist in medicine regarding promotion, achievement of academic rank, and appointment to leadership positions. Fertility and childbearing concerns may contribute to these disparities. Objective: To assess fertility knowledge and concerns and evaluate barriers to family building and impact on academic attrition reported by female physicians. Design, Setting, and Participants: This qualitative study used mixed methods; first, structured 1:1 interviews exploring fertility knowledge and family-building concerns were conducted among 16 female physicians between November 2019 and May 2020. Transcripts were coded in Dedoose and used to develop a survey instrument with subsequent pilot testing conducted among 24 female physicians between April 2020 and September 2020. Data analysis was performed from January 2021 to March 2021. Main Outcomes and Measures: Fertility knowledge, perceptions of peer and institutional support surrounding childbearing, factors contributing to delayed childbearing, and impact of family planning on career decisions. Results: Among 16 women who completed qualitative interviews, 4 (25%) were Asian, 1 (6%) was Black, 1 (6%) was multiracial, and 10 (63%) were White; mean (SD) age was 34.9 (4.0) years. Evaluation of fertility knowledge revealed 3 notable themes: (1) inadequate formal fertility education, (2) informal learning through infertility experiences of patients, peers, or personal struggles, and (3) desire to improve medical education through early introduction and transparent discussions about infertility. Exploration of childbearing concerns similarly revealed several salient themes: (1) high incidence of delayed childbearing, (2) perceived lack of peer and administrative support, and (3) impact of family building on career trajectory. These themes were borne out in pilot testing of the survey instrument: of 24 female physicians (7 Asian women [27%], 1 Black woman [4%], 1 Hispanic or Latinx woman [4%], 1 multiracial woman [4%], 15 White women [58%]; mean [SD] age, 36.1 [6.7] years), 17 (71%) had delayed childbearing and 16 (67%) had altered their career for family-building reasons. Conclusions and Relevance: Qualitative interviews identified fertility and family building concerns among female physicians and were used to develop a tailored survey for women in medicine. These findings suggest that female physicians may delay childbearing and make substantial accommodations in their careers to support family building. A large-scale national survey is needed to better characterize the unique fertility, childbearing, and parenting needs of women in academic medicine to better understand how these concerns may contribute to academic attrition.

Women's preventive services initiative: fertility counseling overlooked.

The 2021 Women's Preventive Services Initiative Well-Woman Chart outlines a framework for incorporating preventive health services recommended by the Women's Preventive Services Initiative, the US Preventive Services Task Force, and Bright Futures based on age, health status, and risk factors. Following the previous guidelines for preventive care, this document failed to offer recommendations or guidelines for infertility screening and fertility counseling in the course of well-woman care. Healthcare providers may be less likely to address fertility with their patients in the absence of clear, evidence-based recommendations, potentially resulting in underinformed reproductive choices and compromised reproductive potential. Given the devastating consequences of infertility and unintended childlessness, we, herein, propose that infertility screening and fertility counseling should become an integral part of well-woman care and that organizations, such as the Women's Preventive Services Initiative, put forth guidelines to assist providers in addressing fertility throughout a woman's reproductive lifespan.

Promises and pitfalls of male contraceptive vaccines.

I have not failed. I've just found 10,000 ways that won't work. -Thomas A. Edison.

Intramuscular progesterone versus 8% Crinone vaginal gel for luteal phase support following blastocyst cryopreserved single embryo transfer: a retrospective cohort study.

BACKGROUND: The optimal route of progesterone administration for luteal support in cryopreserved embryo transfer (CET) has been the subject of much debate. While most published research has pertained to day 3 transfers, recent data on blastocyst CET has suggested that intramuscular progesterone (IMP) is superior to twice daily vaginal Endometrin suppositories for luteal phase support, resulting in significantly higher ongoing pregnancy rates. This study aimed to determine whether IMP is similarly superior to 8% Crinone vaginal gel for luteal phase support following blastocyst CET. METHODS: Autologous and donor oocyte blastocyst cryopreserved single embryo transfer (SET) cycles from January 2014-January 2019 utilizing either 50 mg IMP daily or 90 mg 8% Crinone gel twice daily for luteal support were included. The primary outcome was live birth. Secondary outcomes included biochemical pregnancy, spontaneous abortion, and clinical pregnancy. All analyses were adjusted a priori for oocyte age. Log-binomial regression analysis was performed with differences in outcomes reported as relative risk (RR) with 95% confidence intervals (CI). RESULTS: A total of 1710 cycles were included, of which 1594 utilized IMP and 116 utilized 8% Crinone gel. Demographic and cycles characteristics were similar between the two groups. Compared to cycles utilizing IMP, cycles utilizing Crinone gel resulted in similar rates of live birth (RR 0.91; 95% CI 0.73-1.13), biochemical pregnancy (RR 1.12, 95% CI 0.65-1.92), spontaneous abortion (RR 1.41, 95% CI 0.90-2.20), and clinical pregnancy (RR 1.00, 95% CI 0.86-1.17). CONCLUSIONS: Compared to cryopreserved blastocyst SET cycles utilizing IMP for luteal support, cycles utilizing 8% Crinone gel resulted in similar likelihood of live birth.

The effect of follicular phase length on cycle outcomes and endometrial development in gonadotrophin ovarian stimulation/intrauterine insemination cycles.

RESEARCH QUESTION: Does a shorter follicular phase length (FPL) affect cycle outcomes and endometrial development among women undergoing gonadotrophin ovarian stimulation/intrauterine insemination (OS/IUI)? DESIGN: Retrospective cohort study of 4773 OS/IUI cycles among 2054 patients. FPL was analysed first continuously, then dichotomously using an arbitrary cut-off at the 15th percentile (8 days) to divide cycles into shorter and longer FPL groups. Receiver operating characteristic (ROC) curves were constructed to further analyse the impact of FPL on all outcomes. Primary outcomes included clinical pregnancy, spontaneous abortion, multiple pregnancy and non-viable (ectopic/biochemical) pregnancy rates (CPR, SABR, MPR and NVPR, respectively). Secondary outcomes included endometrial thickness. All analyses controlled for age, day 3 FSH and body mass index. RESULTS: When analysing FPL continuously, CPR increased by 6.0% (adjusted odds ratio [aOR] 1.06, 95% CI 1.03-1.09, P < 0.001) with each additional follicular phase day. Similarly, in the dichotomous analysis, cycles with a longer FPL resulted in higher CPR with 45% higher odds of clinical pregnancy (aOR 1.45, 95% CI 1.07-1.97, P = 0.018). No effect of FPL was noted on NVPR, SABR or MPR. Endometrial thickness increased by 0.09 mm (95% CI 0.06-0.12, P < 0.001) with each additional FPL day and was increased in the longer compared with the shorter FPL group (adjusted mean difference 1.08 mm, 95% CI 0.81-1.34, P < 0.001). CONCLUSIONS: The data suggest that in gonadotrophin OS/IUI cycles, FPL might impact both chance of clinical pregnancy and endometrial thickness, independent of maternal age and ovarian reserve.

Association between blastocyst morphology and pregnancy and perinatal outcomes following fresh and cryopreserved embryo transfer.

PURPOSE: To assess the importance of each blastocyst morphological criteria with pregnancy and perinatal outcomes. METHODS: This single-center retrospective cohort study included blastocyst single embryo transfers (SET) performed between 1/2012-2/2018. Poisson regression was used to evaluate pregnancy outcomes following fresh and cryopreserved embryo transfer (CET) for association with blastocyst expansion, inner cell mass (ICM) quality, and trophectoderm (TE) quality. Among cycles resulting in live birth, associations with preterm birth, small for gestational age (SGA) and large for gestational age (LGA), were evaluated using logistic regression. RESULTS: A total of 1023 fresh and 1222 CET cycles were included, of which 465 (45.1%) fresh and 600 (48.5%) CET cycles resulted in singleton live birth. Clinical pregnancy rates increased with increasing expansion among fresh transfers (p for trend = 0.001) but not CET (p = 0.221), and with TE quality for both fresh and CET cycles (p = 0.005 and < 0.0001, respectively). Live birth rates increased with increasing expansion (fresh p = 0.005, CET p = 0.018) and TE quality (fresh p = 0.028, CET p = 0.023). ICM grade was not associated with pregnancy outcomes; however, higher ICM quality among CET cycles was associated with increased chance of preterm birth (p = 0.005). CONCLUSIONS: In blastocyst SET, blastocyst expansion and TE quality were each associated with clinical pregnancy and live birth. While higher ICM quality was associated with increased chance of preterm birth among CET, no other associations with perinatal outcomes were identified. Clinicians can be reassured that pregnancies from blastocysts with lower expansion, ICM, or TE qualities are not more likely to result in adverse perinatal outcomes.

Pelvic and pulmonary benign metastasizing leiomyoma: A case report.

Seven years after she had a total abdominal hysterectomy for benign leiomyomas, a 46-year-old woman presented with a pelvic mass and multiple pulmonary nodules. She underwent resection of the mass and core needle biopsy of a pulmonary lesion. Histopathologic analysis revealed that both the pelvic and the pulmonary lesions were consistent with benign leiomyomas. Benign metastasizing leiomyoma should be considered if a woman of reproductive age and with a history of leiomyomas presents with extrauterine nodules without evidence of malignancy. The final diagnosis should be based on histopathological examination. Treatment depends on tumor size, location, receptor positivity, and disease progression.

Embryo transfer: timing and techniques.

Since the first successful human in vitro fertilization (IVF) pregnancy nearly 40 years ago, remarkable progress has been made in assisted reproductive technology (ART). Improvements in oocyte retrieval, embryo culture, genetic screening, and embryo selection have contributed to dramatic improvements in IVF outcomes. A more robust understanding of embryologic development has driven innovation in not only the timing of embryo transfer but also the number of embryos to transfer. Additionally, overcoming the technical hurdle of embryo vitrification has given both physicians and patients several benefits including the flexibility to mitigate effects of superovulation on the endometrium, limit the number of embryos transferred, afforded an opportunity to screen the quality of embryos both by evaluating in vitro development as well as preimplantation genetic testing. Within this review, we highlight in a stepwise fashion the considerations for embryo transfer timing and technique that physicians and patients alike must consider when undergoing an IVF cycle.