Do women with severely diminished ovarian reserve undergoing modified natural cycles benefit from earlier trigger at smaller follicle size?

OBJECTIVE: Would trigger and oocyte collection at smaller follicle sizes decrease the risk of premature ovulation while maintaining the reproductive potential of oocytes in women with severely diminished ovarian reserve in modified natural cycle IVF? METHODS: Retrospective cohort study including women who had at least one unsuccessful cycle (due to no response) of conventional ovarian stimulation with a high dosage of gonadotropins and subsequently underwent a modified natural cycle with a solitary growing follicle (i.e., only one follicle above >10mm at the time of trigger). The association between follicle size at trigger and various cycle outcomes was tested with regression analyses. RESULTS: A total of 160 cycles from 110 patients were included in the analysis. Oocyte pick-up (OPU) was performed in 153 cycles, 7 cycles were canceled due to premature ovulation. Patients who received their trigger shot at smaller follicle sizes (≤15mm) had significantly lower premature ovulation and thus higher OPU rates (98.3% vs. 94.0%, adjusted OR: 8.55, 95% CI: 1.30 - 172.2, P=0.048) compared to those who received it at larger follicle sizes (>15mm). In the multivariable analyses, smaller follicle sizes at trigger (>10 to ≤13mm, >13 to ≤15mm, >15mm to ≤17mm) were not significantly associated with a lower rate of cumulus-oocyte-complex (COC), metaphase II oocytes (MIIs), or blastulation compared to the >17mm group. In sensitivity analyses including the first cycle of each couple, the maturity rate among those with a COC retrieval was highest in follicle sizes >15 to ≤17mm (92.3%) and >13 to ≤15mm (91.7%), followed by >10 to ≤13mm (85.7%) and lowest in the >17mm group (58.8%). Five euploid blastocysts developed from 48 fertilized MIIs during the study period with follicle sizes at trigger 12mm (3), 14 mm (1), and 16mm (1). Four were transferred resulting in two live births, both developing from follicles with a size at trigger of 12mm. CONCLUSION: The ideal follicle size for triggering oocyte maturation may be smaller in women with severely diminished ovarian reserve managed on a modified natural cycle compared to conventional cut-offs. The risk of OPU cancellation was higher in women triggered above 15 mm, and the yield of mature oocytes was not adversely affected in women triggered at >13 to ≤15mm compared to >15mm to ≤17mm. Waiting for follicles to reach sizes above 17mm may be detrimental to achieving optimal outcomes. This article is protected by copyright. All rights reserved.

The combination of dydrogesterone and micronized vaginal progesterone can render serum progesterone level measurements on the day of embryo transfer and rescue attempts unnecessary in an HRT FET cycle.

PURPOSE: To evaluate the role of serum progesterone (P4) on the day of embryo transfer (ET) when dydrogesterone (DYD) and micronized vaginal progesterone (MVP) are combined as luteal phase support (LPS) in a hormone replacement therapy (HRT) frozen ET (FET) cycles. METHODS: Retrospective study, including single euploid HRT FET cycles with DYD and MVP as LPS and P4 measurement on ET day. Initially, patients with P4 levels < 10 ng/ml increased MVP to 400 mg/day; this "rescue" was abandoned later. RESULTS: 560 cycles of 507 couples were included. In 275 women, serum P4 level was < 10 ng/ml on the ET day. Among those with low P4 levels, MVP dose remained unchanged in 65 women (11.6%) and was increased in 210 women (37.5%). Women with P4 levels ≥ 10 ng/ml continued LPS without modification. Overall pregnancy rates in these groups were 61.5% (40/65), 54.8% (115/210), and 48.4% (138/285), respectively (p = n.s.). Association of serum P4 levels with ongoing pregnancy rates was analyzed in women without any additional MVP regardless of serum P4 levels (n = 350); multivariable analysis (adjusted for age, BMI, embryo quality (EQ)) did not show a significant association of serum P4 levels with OPR (OR 0.96, 95% CI 0.90-1.02; p = 0.185). Using inverse probability treatment weights, regression analysis in the weighted sample showed no significant association between P4 treatment groups and OP. Compared to fair EQ, the transfer of good EQ increased (OR 1.61, 95% CI 1.22-2.15; p = 0.001) and the transfer of a poor EQ decreased the odds of OP (OR 0.73, 95% CI 0.55-0.97; p = 0.029). CONCLUSION: In HRT FET cycle, using LPS with 300 mg/day MVP and 30 mg/day DYD, it appears that serum P4 measurement and increase of MVP in patients with P4 < 10 ng/ml are not necessary.

How to identify patients who would benefit from delayed-matured oocytes insemination: a sibling oocyte and ploidy outcome study.

STUDY QUESTION: Which patients might benefit from insemination of delayed-matured oocytes? SUMMARY ANSWER: Delayed-matured oocytes had a ≥50% contribution to the available cohort of biopsied blastocysts in patients with advanced maternal age, low maturation, and/or low fertilization rates. WHAT IS KNOWN ALREADY: Retrieved immature oocytes that progress to the MII stage in vitro could increase the number of embryos available during ICSI cycles. However, these delayed-matured oocytes are associated with lower fertilization rates and compromised embryo quality. Data on the ploidy of these embryos are controversial, but studies failed to compare euploidy rates of embryos derived from delayed-matured oocytes to patients' own immediate mature sibling oocytes. This strategy efficiently allows to identify the patient population that would benefit from this approach. STUDY DESIGN, SIZE, DURATION: This observational study was performed between January 2019 and June 2021 including a total of 5449 cumulus oocytes complexes from 469 ovarian stimulation cycles, from which 3455 inseminated matured oocytes from ICSI (n = 2911) and IVF (n = 544) were considered as the sibling controls (MII-D0) to the delayed-matured oocytes (MII-D1) (n = 910). Euploidy rates were assessed between delayed-matured (MII-D1) and mature sibling oocytes (MII-D0) in relation to patients' clinical characteristics such as BMI, AMH, age, sperm origin, and the laboratory outcomes, maturation, fertilization, and blastocyst utilization rates. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 390 patients undergoing IVF/ICSI, who had at least one metaphase I (MI) or germinal-vesicle (GV) oocyte on the day of oocyte collection (Day 0), which matured in 20-28 h after denudation were included. MI and GV oocytes that matured overnight were inseminated on the following day (Day 1, MII-D1) by ICSI. Only cycles planned for preimplantation genetic testing for aneuploidy using fresh own oocytes were included. MAIN RESULTS AND THE ROLE OF CHANCE: Fertilization (FR) and blastocyst utilization rates were significantly higher for MII-D0 compared to delayed-matured oocytes (MII-D1) (69.5% versus 55.9%, P < 0.001; and 59.5% versus 18.5%, P < 0.001, respectively). However, no significant difference was observed in the rate of euploid embryos between MII-D0 and MII-D1 (46.3% versus 39.0%, P = 0.163). For evaluation of the benefit of inseminating MI/GV oocytes on D1 per cycle in relation to the total number of biopsied embryos, cycles were split into three groups based on the proportion of MII-D1 embryos that were biopsied in that cycle (0%, 1-50%, and ≥50%). The results demonstrate that patients who had ≥50% contribution of delayed-matured oocytes to the available cohort of biopsied embryos were those of advanced maternal age (mean age 37.7 years), <10 oocytes retrieved presenting <34% maturation rate, and <60% fertilization rate. Every MII oocyte injected next day significantly increased the chances of obtaining a euploid embryo [odds ratio (OR) = 1.83, CI: 1.50-2.24, P < 0.001] among MII-D1. The odds of enhanced euploidy were slightly higher among the MII-D1-GV matured group (OR = 1.78, CI: 1.42-2.22, P < 0.001) than the MII-D1-MI matured group (OR = 1.54, CI: 1.25-1.89, P < 0.001). Inseminating at least eight MII-D1 would have >50% probability of getting a euploid embryo among the MII-D1 group. LIMITATIONS, REASONS FOR CAUTION: ICSI of MII-D1 was performed with the fresh or frozen ejaculates or testicular samples from the previous day. The exact timing of polar body extrusion of delayed-matured MI/GV was not identified. Furthermore, the time point of the final oocyte maturation to MII for the immature oocytes and for the oocytes inseminated by IVF could not be identified. WIDER IMPLICATIONS OF THE FINDINGS: The results of this study might provide guidance to the IVF laboratories for targeting the patient's population who would benefit from MII-D1 ICSI without adhering to unnecessary costs and workload. STUDY FUNDING/COMPETING INTEREST(S): No external funding was received for this study. There are no conflicts of interest to be declared for any of the authors. There are no patents, products in development, or marketed products to declare. TRIAL REGISTRATION NUMBER: N/A.

Are systemic progesterone levels in true natural cycle euploid frozen embryo transfers with luteal phase support predictive for ongoing pregnancy rates?

STUDY QUESTION: Are serum progesterone (P4) levels on the embryo transfer (ET) day predictive of ongoing pregnancy (OP) following a single euploid blastocyst transfer in a natural cycle (NC) when luteal phase support is routinely given? SUMMARY ANSWER: In single euploid frozen ETs in NC, P4 levels on ET day are not predictive for OP, when luteal phase support (LPS) is routinely added after the ET. WHAT IS KNOWN ALREADY: In an NC frozen embryo transfer (FET), P4 produced by the corpus luteum initiates secretory transformation of the endometrium and maintains pregnancy after implantation. There are ongoing controversies on the existence of a P4 cutoff level on the ET day, being predictive for the chance of OP as well as of the possible role of additional LPS after ET. Previous studies in NC FET cycles, evaluating and identifying P4 cutoff levels did not exclude embryo aneuploidy as a possible reason for failure. STUDY DESIGN, SIZE, DURATION: This retrospective study analyzed single, euploid FET in NC, conducted in a tertiary referral IVF centre between September 2019 and June 2022, for which measurement of P4 on the day of ET and the treatment outcomes were available. Patients were only included once into the analysis. Outcome was defined as OP (ongoing clinical pregnancy with heartbeat, >12 weeks) or no-OP (not pregnant, biochemical pregnancy, early miscarriage). PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients with an ovulatory cycle and a single euploid blastocyst in an NC FET cycle were included. Cycles were monitored by ultrasound and repeated measurement of serum LH, estradiol, and P4. LH surge was identified when a rise of 180% above the previous level occurred and P4 levels of ≥1.0 ng/ml were regarded as confirmation of ovulation. The ET was scheduled on the fifth day after P4 rise and vaginal micronized P4 was started on the day of ET after P4 measurement. MAIN RESULTS AND THE ROLE OF CHANCE: Of 266 patients included, 159 (59.8%) patients had an OP. There was no significant difference between the OP- and no-OP-groups for age, BMI, and day of embryo biopsy/cryopreservation (Day 5 versus Day 6). Furthermore, P4 levels were not different between the groups of patients with OP (P4: 14.8 ng/ml (IQR: 12.0-18.5 ng/ml)) versus no-OP (P4: 16.0 ng/ml (IQR: 11.6-18.9 ng/ml)) (P = 0.483), and no differences between both groups, when P4 levels were stratified into categories of P4 levels of >5 to ≤10, >10 to ≤15, >15 to ≤20, and >20 ng/ml (P = 0.341). However, both groups were significantly different for the embryo quality (EQ), defined by inner cell mass/trophectoderm, as well as when stratified into three EQ groups (good, fair, and poor) (P = 0.001 and 0.002, respectively). Stratified EQ groups remained the only significant parameter influencing OP in the uni- and multivariate analyses (P = 0.002 and P = 0.004, respectively), including age, BMI, and P4 levels (each in categories) and embryo cryopreservation day. Receiver operator characteristic curve for the prediction of an OP revealed an AUC of 0.648 when age, BMI and EQ groups were included into the model. The inclusion of P4 measurement on ET day into the model did not add any benefit for OP prediction (AUC = 0.665). LIMITATIONS, REASONS FOR CAUTION: The retrospective design is a limitation. WIDER IMPLICATIONS OF THE FINDINGS: Monitoring serum P4 levels can be abandoned in NC FET cycles with routine LPS as they do not seem to be predictive of live birth. STUDY FUNDING/COMPETING INTEREST(S): No external funding was used for this study. The authors state that they do not have any conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

Effect of chamber characteristics, loading and analysis time on motility and kinetic variables analysed with the CASA-mot system in goat sperm.

Several factors unrelated to the semen samples could be influencing in the sperm motility analysis. The aim of the present research was to study the effect of four chambers with different characteristics, namely; slide-coverslip, Spermtrack, ISAS D4C10, and ISAS D4C20 on the sperm motility. The filling procedure (drop or capillarity) and analysis time (0, 120 and 240s), depth of chamber (10 or 20µm) and field on motility variables were analysed by use of the CASA-mot system in goat sperm. Use of the drop-filling chambers resulted in greater values than capillarity-filling chambers for all sperm motility and kinetic variables, except for LIN (64.5% compared with 56.3% of motility for drop- and capillarity-filling chambers respectively, P<0.05). There were no significant differences in total sperm motility between different chamber depths, however, use of the 20µm-chambers resulted in greater sperm progressive motility rate, VSL and LIN, and less VCL and VAP than chambers with a lesser depth. There was less sperm motility and lesser values for kinetic variables as time that elapsed increased between sample loading and sperm evaluation. For sperm motility, use of droplet-loaded chambers resulted in similar values of MOT in all microscopic fields, but sperm motility assessed in capillarity-loaded chambers was less in the central fields than in the outermost microscopic fields. For goats, it is recommended that sperm motility be analysed using the CASA-mot system with a drop-loaded chamber within 2min after filling the chamber.