P-389 Elevated BMI in oocyte donors or recipients is associated with a higher risk of miscarriage after blastocyst transfer: a multicenter analysis of 1544 procedures

Study question

Is an elevated BMI in either oocyte donors or recipients associated with a higher risk of miscarriage after blastocyst transfer?

Summary answer

Overweight in oocyte donors and/or obesity in recipients are associated with a 2X-higher risk of miscarriage in egg donation cycles.

What is known already

Several basic-science, clinical and epidemiological studies revealed an association between BMI and infertility, suggesting a J-shaped relationship: both underweight and especially overweight/obese women can suffer from reproductive impairments. In particular, overweight-obese women are more prone to suffer from a miscarriage even when euploid blastocysts are transferred. Yet, it is still unclear whether this is the consequence of an altered oocyte (and then embryonic) competence and/or an impaired endometrial receptivity. In this context, oocyte donation cycles represent the ideal clinical setting to shed some light on an issue with numerous social, clinical, and logistic implications.

Study design, size, duration

Retrospective study including 1544 blastocyst single embryo transfers (SETs) conducted in oocyte donation cycles (Jan2019-May2021). All oocytes were vitrified at 2 egg banks in Spain and warmed at 8 clinics part of the same network. The primary outcome was the miscarriage rate (<22nd gestational weeks) per clinical pregnancy according to donors’ and/or recipients’ BMI. Four BMI clusters were defined (underweight: <18.5; normal-weight: 18.5-24.9; over-weight: 25-30; obese: >30).

Participants/materials, setting, methods

66.1%,4.9%,20.3% and 8.7% of SETs were conducted in normal-weight, underweight, overweight, and obese recipients. 81.4%,4.5% and 14.1% of SETs with oocytes derived from normal-weight, underweight, and overweight donors. The putative confounders investigated were egg bank, IVF center, fresh/vitrified-warmed SET, blastocyst quality/day, recipient/donor age, endometrial preparation protocol, number of consecutive SET. Before SET, we requested blood test for infections and TORCH, thyroid function, coagulation and immunological assessment, cardiological, gynecologic and breast evaluation.

Main results and the role of chance

Overweight-obese recipients were slightly older (43.0±4.0yr) than normal-weight ones (42.2±3.8yr; p < 0.01). Similarly, overweight donors were slightly older (27.5±4.5yr) than normal-weight ones (26.4±4.3yr; p < 0.01). Therefore, all outcomes were adjusted for recipients’/donors’ age. The overall positive pregnancy rate per blastocyst SET and biochemical pregnancy loss rate were 51.8% and 12.6%. No association was reported between either recipients’ or donors’ BMI and both these secondary outcomes. Conversely, higher recipients’ and donors’ BMI were significantly associated with a higher risk of miscarriage after blastocyst SET (multivariate-OR 1.05, 95%CI 1.01-1.1, adjusted-p=0.05; multivariate-OR 1.1, 95%CI 1.04-1.2, adjusted-p<0.01). The most significant differences were reported for obese versus normal-weight recipients (N = 18/64,28.1% versus N = 73/448,16.3%; p = 0.03, power=60%; multivariate-OR 1.8, 95%CI 1.01-3.4, adjusted-p=0.05) and for overweight versus normo-weight donors (N = 31/111,27.9% versus N = 94/561,16.8%; p < 0.01, power=73%; multivariate-OR 1.9, 95%CI 1.16-3.0, adjusted-p=0.01). In the 14 clinical pregnancies where the oocytes derived from overweight donors and the blastocysts were transferred to obese women the miscarriage rate was 50%; the same outcome in normal-weight recipients using oocytes from normal-weight donors was 15% (N = 55/366; p < 0.01, power=85%; OR 5.6, 95%CI 1.8-16.8, p < 0.01). The data were similar across both egg banks and all IVF centers. All other parameters assessed were not associated with the primary outcome under investigation.

Limitations, reasons for caution

The study is retrospective, and the sample size in each sub-group shall be increased. Moreover, BMI is a gross marker of an individual’s metabolic status. Future studies on more accurate markers like percentage and localization of adipose tissue assessed through techniques like bioelectrical impedance analyses are desirable.

Wider implications of the findings

Both oocyte competence and endometrial receptivity might be impaired from unbalanced nutritional intakes. More studies on this topic are certainly required. Whenever possible, nutritional/lifestyle adjustments should be encouraged in obese patients because of their higher risk of miscarriage, and a BMI limit should be considered also when recruiting egg donors.

Trial registration number

Not applicable

P-442 A new option to thaw slow-frozen human ovarian tissue in cancer patients: efficacy and safety of the combination of different cryopreservation kits

Study question

Is follicular viability of slow-frozen human ovarian tissue preserved if rapid thawing is performed using a solution containing extracellular cryoprotectant only?

Summary answer

Follicular viability is preserved even using thawing solutions containing extracellular cryoprotectant only, combining kits with different composition.

What is known already

Ovarian tissue cryopreservation is an alternative option to oocytes or embryos for fertility preservation in cancer patients facing gonadotoxic treatments. To date, each brand producing kits approved for the slow-freezing of human ovarian tissue recommends the use of its own thawing kit. However, a potential single protocol based on the use of any extracellular cryoprotectant has already been proposed for human oocytes and embryos. The current study aims at finding alternative options to thaw cryopreserved human ovarian tissue when the original kit was withdrawn from the market and only one CE-marked kit was available, even with different composition in cryoprotectants.

Study design, size, duration

Ovarian tissue cryopreservation of ten cancer patients (18.3 ± 7.6 years) undergoing fertility preservation between 2001 and 2012 was performed following a slow-freezing protocol with 1.5M 1,2 PROH and 0.5M Sucrose. Once deceased, for each patient, cortical fragments were prospectively thawed and equally allocated into two groups: i) fragments thawed using 0.5-1M 1,2 PROH and 0.3M Sucrose (PROH+S Group, n = 73); ii) fragments thawed following an adjusted protocol with 0.5M Sucrose only (S Group, n = 73).

Participants/materials, setting, methods

Post thawing follicular density/mm2, integrity (%) and the presence of interstitial oedema were assessed by histological and ultrastructural analysis performed after formalin fixation and haematoxylin/eosin staining. Follicular viability was evaluated by the expression of markers of proliferation (Ki67) and of vascularization (CD31) by immunohistochemistry after a 24h culture in Iscove’s modified Dulbecco’s medium at 37 °C and 6% CO2. A paired comparison was performed referring to the fresh tissue of the same patient as control.

Main results and the role of chance

The histological evaluation performed after thawing revealed that follicles were predominantly primordial (91%), with no follicles larger than the proliferating primary stage. A significant reduction of follicular density per mm2 was observed in both study groups (14.2 ± 12.0 vs. 15.1 ± 14.0 for PROH+S and S Group, respectively; p = 0.4) compared to the fresh tissue (27.2 ± 31.6; p = 0.04) as well as a remarkable decreased of the proportion of intact follicles (39.3 ± 17.1 vs. 25.5 ± 9.8; p = 0.2) compared to the fresh tissue (98.1 ± 1.4; p = 0.002). Thawed samples equally showed interstitial oedema and increased stromal cell vacuolization and chromatin clumping. Ki67 positive staining of active proliferating cells revealed a comparable proportion of viable follicles between thawed samples (46.3 ± 20.8 vs. 28.3 ± 27.9 for PROH+S and S Group, respectively; p = 0.2). Finally, the expression of the endothelial marker CD31 in the thawed samples suggested an equivalent number of blood vessels per mm2 (43.8 ± 34.3 vs. 41.7 ± 44.8; p = 0.6).

Limitations, reasons for caution

Single centre study with a limited sample size. Only 24h of in vitro culture was assessed. The use of the freezing medium corresponding to the Sucrose only solution was not tested. Clinical outcomes after ovarian tissue transplantation should be evaluated before drawing final conclusion.

Wider implications of the findings

First evidence of the feasible application of a “Universal Warming” protocol, irrespective of brand and cryoprotectants, for the rapid thawing of slow-frozen human ovarian tissue. IVF centres would be provided with alternative options to thaw ovarian tissue for restoring reproductive potential in cancer patient undergoing ovarian transplantation.

Trial registration number

Not applicable

The effect of extended cryo-storage following vitrification on embryo competence: a systematic review and meta-analysis

PURPOSE

Few studies explored whether prolonged cryo-storage after vitrification affects embryo competence and perinatal outcomes. This systematic review and meta-analysis aims at highlighting any putative impact of cryo-storage duration on cryo-survival, miscarriage, live birth and major malformations.

METHODS

A systematic review was performed using MEDLINE (PubMed), ISI Web of Knowledge, Scopus and Embase databases up to June 2021. Data were combined to obtain a pooled OR, and meta-analysis was conducted using a random effects model. Out of 1,389 screened abstracts, 22 papers were assessed for eligibility, and 5 studies were included (N = 18,047 embryos). Prolonged cryo-storage was defined as > 12 months (N = 3389 embryos). Subgroup analysis was performed for untested vitrified cleavage stage embryos (N = 1739 embryos) and for untested and euploid vitrified blastocysts (N = 13,596 and 2712 embryos, respectively).

RESULTS

Survival rate, miscarriage, live birth and major malformation rates were all similar in the two groups.

CONCLUSION

These data further support the safety of long-term cryo-storage of human embryos beyond 12 months. This is reassuring for good prognosis patients with surplus embryos, couples seeking a second child from supernumerary embryos and women postponing the transfer for clinical or personal reasons.

P–606 A second stimulation in the same ovarian cycle rescues advanced-maternal-age patients obtaining ≤ 3 blastocysts after the conventional approach by preventing treatment-discontinuation

Study question

Is double stimulation in the same ovarian cycle (DuoStim) a valuable strategy to rescue advanced-maternal-age patients obtaining ≤ 3 blastocysts for chromosomal-testing after conventional stimulation?

Summary answer

DuoStim is effective to prevent treatment discontinuation thereby increasing the 1-year cumulative-live-birth-rate among advanced-maternal-age patients obtaining 0–3 blastocysts after a first conventional stimulation.

What is known already

Folliculogenesis is characterized by continuous waves of follicular growth. DuoStim approach exploits these dynamics to conduct two stimulations in a single ovarian cycle and improve the prognosis of advanced-maternal-age and/or reduced-ovarian-reserve women. Independent groups worldwide successfully adopted DuoStim with various regimens reporting similar oocyte/embryo competence after both stimulations. Recently, we have demonstrated the fruitful adoption of DuoStim in patients fulfilling the Bologna criteria, especially because of the prevention of treatment discontinuation. Here we aimed at investigating whether DuoStim can be adopted to rescue poor prognosis patients obtaining 0–3 blastocysts after the conventional approach.

Study design, size, duration

Proof-of-concept matched case-control study. All patients obtaining 0–3 blastocysts after conventional-stimulation between 2015–2018 were proposed DuoStim. The 143 couples who accepted were matched for maternal age, sperm factor, cumulus-oocyte-complexes and blastocysts obtained after the first stimulation to 143 couples who did not. The primary outcome was the 1-year cumulative-live-birth-rate. If not delivering, the control group had 1 year to undergo a second attempt with conventional-stimulation. All treatments were concluded (live-birth achieved or no euploid left).

Participants/materials, setting, methods

Only GnRH-antagonist with recombinant-gonadotrophins and agonist trigger stimulation protocols were adopted. All cycles entailed ICSI with ejaculated sperm, blastocyst culture, trophectoderm biopsy, comprehensive-chromosome-testing and vitrified-warmed euploid single-embryo-transfer(s). Cumulative-live-birth-rate was calculated per patient considering both stimulations in the same ovarian cycle (DuoStim group) or up to two stimulations in 1 year (control group). Treatment discontinuation rate in the control group was calculated as patients who did not return for a second stimulation among non-pregnant ones.

Main results and the role of chance

Among the 286 couples included (41.0±2.9yr;4.9±3.1 cumulus-oocytes-complexes and 0.8±0.9 blastocysts), 126 (63 per group), 98 (49 per group), 52 (26 per group) and 10 (5 per group) obtained 0,1,2 and 3 blastocysts after the first stimulation, respectively. The cumulative-live-birth-rate was 9% in the control group after the first attempt (N = 13/143). Among the 130 non-pregnant patients, only 12 returned within 1-year (165±95days later;discontinuation rate=118/130,91%), and 3 delivered. Thus, the cumulative-live-birth-rate from two stimulations in 1-year was 11% (N = 16/143). In the DuoStim group, the cumulative-live-birth-rate was 24% (N = 35/143; Fisher’s-exact-test< 0.01,power=80%). The odds-ratio of delivering in the DuoStim versus the control group adjusted for all matching criteria was 3.3,95%CI:1.6–7.0,p<0.01. This difference (0%,22%,15% and 20% in the control versus 10%,31%,46% and 40% in the DuoStim group among patients obtaining 0,1,2 and 3 blastocysts at the first stimulation, respectively) is mainly due to treatment discontinuation in the control group (98%,65%,77% and 80% among patients obtaining 0,1,2 and 3 blastocysts at the first stimulation, respectively) and the further increased maternal age at the time of second retrieval (∼6 months). Notably, 2 patients delivered 2 live-births after DuoStim (none in the control) and 14 patients with a live-birth have euploid blastocysts left (2 in the control).

Limitations, reasons for caution

Randomized-controlled-trials and cost-effectiveness analyses are desirable to confirm these data. Moreover, 75% of the patients included were >39yr and 44% obtained no blastocyst after the first stimulation. Therefore future studies among younger women and/or more women obtaining ≥1 blastocyst are advisable to set reasonable cut-off values to apply this strategy.

Wider implications of the findings: A second stimulation in the same ovarian cycle might be envisioned as a rescue strategy for poor IVF outcomes after a first stimulation, so to prevent treatment discontinuation and increase the cumulative-live-birth-rate. This is feasible since 6–7 days span the first and the second stimulation in the DuoStim protocol.

Trial registration number

none

18F-FDG PET/CT is a prognostic biomarker in patients affected by bone metastases from breast cancer in comparison with 18F-NaF PET/CT

Aim: To compare 18F-FDG PET/CT and 18F-NaF PET/CT with respect to disease prognostication and outcome in patients affected by bone metastases from breast cancer (BC). Patients, methods: We retrospectively investigated 32 women with BC and documented bone metastases. Semi-quantitative parameters were applied to 18F-FDG PET/CT and 18F-Na PET/CT in order to evaluate disease extent and tumour metabolism. We used time-to-event analyses (Kaplan Meier and COX proportional hazard methods) to estimate progression-free (PFS) and overall survival (OS) in order to assess the independent prognostic value of 18F-FDG PET/CT and 18F-Na PET/CT. Results: The sensitivity of 18F-NaF PET/CT (100%) was higher (p < 0.05) than that of 18F-FDG PET/CT (72% and 72%). None of the 18F-FDG PET/CT-negative patients showed disease progression at the end of follow-up. After adjustment for age, Ki-67 levels, presence of visceral metastases, hormone therapy, duration of bone disease and response to first-line therapy, only 18F-FDG SUV mean [HR 15.7, 95% confidence interval (CI) 1.15-214.5] and 18F-FDG whole-body bone metabolic burden (WB-B-MB) (HR 16.9; 95%CI 1.87-152.2) were independently and significantly associated with OS. None of the 18F-NaF PET/CT parameters were associated with OS. None of the conventional clinical prognostic parameters remained significantly associated with OS after the inclusion of PET/ CT parameters in the model. Conclusion: 18F-FDG PET/CT is independently associated with OS in BC patients with bone metastases and its prognostic impact seems to be higher than conventional clinical and biological prognostic factors. Although 18F-NaF PET/CT has a higher diagnostic sensitivity than 18F-FDG PET/ CT, it is not independently associated with OS.

Preserved insulin sensitivity and {beta}-cell activity, but decreased glucose effectiveness in normal-weight women with the polycystic ovary syndrome

Insulin resistance and hyperinsulinemia are often considered intrinsic features of the polycystic ovary syndrome (PCOS). Nevertheless, conflicting results of insulin sensitivity and secretion have been obtained in the subgroup of normal-weight women with PCOS. Differences in body composition, ethnicity, and diet composition and a family history of metabolic diseases may act as confounding variables in women with PCOS. In the present study, insulin sensitivity and secretion were estimated by an iv glucose tolerance test (IVGTT), analyzed by minimal models, in 20 normal-weight healthy women with PCOS and no family history of type 2 diabetes mellitus and in 20 normally ovulating women, matched for age and body mass index. Insulin sensitivity [mean (95% confidence intervals); PCOS 4.0 (2.8-5.1) vs. controls 4.5 (3.5-5.4) 10(-4) min(-1)/microU.ml], and insulin secretion, expressed as the acute insulin response to glucose [PCOS 3.7 (3.3-4.2) vs. controls 3.7 (3.4-4.0) microU/ml] were similar in the two groups. The women with PCOS showed an increased proportion of total body fat (PCOS 29% vs. controls 27.2%; P < 0.01). They also showed decreased glucose effectiveness, i.e. the proportion of glucose uptake independent from insulin activity [PCOS 2.6 (2.1-3.0) vs. controls 3.8 (3.0-4.6) mg x 100 min(-1); P = 0.01]. The levels of insulin sensitivity and of glucose effectiveness did not correlate in either group. Whether the isolated finding of decreased glucose effectiveness could reflect an early stage in the development of the metabolic aberrations often associated with the syndrome remains to be clarified.

Phase contrast magnetic resonance of the spinal cord preliminary results in spinal cord arterio-venous malformations

In spite of the recent advances in neuroradiology including the CT scan and the spin-echo-magnetic resonance (MR), accurate diagnosis of arteriovenous malformations (AVMs) involving the spinal cord is still based on selective angiography. This last procedure is invasive and needs to be repeated during the follow up. Phase contrast angio MR was performed with a 0.5 Tesla unit on 12 patients with an AVM involving the spinal cord (7 intramedullary AVMs, 4 perimedullary fistulas, and 1 dural fistula with perimedullary venous drainage); 4 of these were investigated before and after treatment. Angio MR showed abnormal vascular patterns within the spinal canal in all cases, without distinguishing between arteries and veins; the nidus of the intramedullary AVMs was displayed in all cases. Angio MR provided images of the whole AVMs comparable to the angiographic pictures, in contrast to the spin-echo MR, which provided only discontinued images of the vessels. The efficient range of velocity providing images varied, according to the type of the malformation (slow for dural fistulas, rapid for intra-medullary AVMs). In the 4 patients investigated after treatment, comparison of the images obtained before and after treatment permitted assessment of the degree of occlusion of the malformation. Finally, angio MR as a complement of spin-echo MR can now be used as a reliable tool for detection of spinal cord AVMs, assessing the indication for angiography, and, furthermore, it can probably replace most of the post-operative control angiographies.(ABSTRACT TRUNCATED AT 250 WORDS)

Sudden cervical pain: spontaneous cervical epidural hematoma

Three cases of cervical epidural hematoma are reported. Acute neck pain usually associated with a mild effort, closely followed by radicular pain and a neurologic deficit below the lesion is the typical presentation of this extremely rare and difficult diagnosis. As prognosis depends on preoperative neurologic state, the authors emphasize the importance of prompt identification of this lesion. The diagnosis is confirmed by computed tomography, and emergency neurosurgical laminectomy is mandatory.

Superposition of ballistic on steady contractions in man

In a visual reaction time task, human subjects superimposed isometric ballistic contractions on a maintained activity in the soleus or anterior tibial muscle. Since there were good reasons to believe that the supraspinal motor commands for the ballistic contractions were independent of those for the background activity, the interaction between the motor commands for the ballistic and for the steady contractions could be studied at the spinal level. If ballistic and steady contractions were in the same direction, the EMG burst and torque changes associated with the ballistic contraction were nearly constant irrespective of the maintained steady flexion force. This was true if a muscle was activated to about 5% of its maximum force as the soleus muscle during plantar flexions and if it was activated to about 40% of its maximum force as the anterior tibial muscle during dorsal flexions. If ballistic and steady contractions were in opposite directions the torque changes related to the ballistic contraction increased linearly with the background activity. This relation was caused by a reduction in antagonist activity starting about 50 ms before the agonist EMG burst and not by an increased agonist burst, the latter remaining independent of background activity. These results imply that the input-output relationship of the motoneuronal pool is nearly linear. The functional basis of this relation is the size principle which is valid during continuous and ballistic contractions. The number of motor units recruited for the ballistic contraction is adjusted according to their force such that the contraction amplitude remains constant.