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10. Do women with severely diminished ovarian reserve undergoing modified natural‐cycle in‐vitro fertilization benefit from earlier trigger at smaller follicle size?

Author

Lawrenz, B., Kalafat, E., Ata, B., Melado, L., Del Gallego, R., Elkhatib, I., and Fatemi, H.

Abstract

ABSTRACT Objective Methods Results Conclusions To evaluate whether trigger and oocyte collection at a smaller follicle size decreases the risk of premature ovulation while maintaining the reproductive potential of oocytes in women with a severely diminished ovarian reserve undergoing modified natural‐cycle in‐vitro fertilization.This was a 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 > 10 mm at the time of trigger). The association between follicle size at trigger and various cycle outcomes was tested using regression analyses.A total of 160 ovarian stimulation cycles from 110 patients were included in the analysis. Oocyte pick‐up (OPU) was performed in 153 cycles and 7 cycles were canceled due to premature ovulation. Patients who received their trigger at smaller follicle sizes (≤ 15 mm) had significantly lower rates of premature ovulation and thus higher rates of OPU (98.9% vs 90.8%; odds ratio, 9.56 (95% CI, 1.58–182.9); P = 0.039) compared with those who received their trigger at larger follicle sizes (> 15 mm). On multivariable analysis, smaller follicle sizes at trigger (> 10 to 13 mm, > 13 to 15 mm, > 15 mm to 17 mm) were not associated significantly with a lower rate of cumulus–oocyte complex (COC) retrieval, metaphase‐II (MII) oocytes or blastulation when compared to the > 17‐mm group. On sensitivity analysis including only the first cycle of each couple, the maturity rate among those with COC retrieval was highest in follicle sizes > 15 to 17 mm (92.3%) and > 13 to 15 mm (91.7%), followed by > 10 to 13 mm (85.7%) and lowest in the > 17‐mm group (58.8%). During the study period, five euploid blastocysts developed from 48 fertilized MII oocytes with follicle sizes of 12 mm (n = 3), 14 mm (n = 1) and 16 mm (n = 1) at trigger. Of those, four were transferred and resulted in two live births, both of which developed from follicles with a size at trigger of 12 mm.The ideal follicle size for triggering oocyte maturation may be smaller in women with a severely diminished ovarian reserve managed on a modified natural cycle when compared to conventional cut‐offs. The risk of OPU cancellation was significantly higher in women triggered at follicle size > 15 mm and the yield of mature oocytes was not adversely affected in women triggered at follicle size > 13 to 15 mm compared with > 15 to 17 mm. Waiting for follicles to reach sizes > 17mm may be detrimental to achieving optimal outcome. © 2024 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Published
2024
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31. Impact of preimplantation genetic testing for aneuploidies (PGT-A) on first trimester biochemical markers – PAPP-A (placenta-associated plasma protein) and free b-hCG (human chorionic gonadotropin).

Author

Markova, D., Kagan, O., Hoopmann, M., Abele, H., Coughlan, C., Abecia, E., Fatemi, H. M., and Lawrenz, B.

Subjects
CHORIONIC gonadotropins, BLOOD proteins, BIOMARKERS, GENETIC testing, EMBRYO transfer
Abstract

Objective: The objective of the study was to study the effect of preimplantation genetic testing for aneuploidies (PGT-A) performed at blastocyst stage on the levels of first trimester biomarkers. Methods: This is an observational, collaborative, retrospective study. Seven hundred and twenty-eight patients were included in the study. Patients were with singleton pregnancies resulting from either natural conception (NC), or assisted reproductive techniques (ARTs) with PGT-A and frozen embryo transfer (FET) (ART/PGT-A/FET) or after ART without PGT-A and fresh ET (ART/no PGT-A/fresh ET) or FET (ART/no PGT-A/FET), who had first trimester combined screening test between 11 and 14 gestational weeks. They were stratified into four groups: group A (ART/PGT-A/FET) – 143 patients; group B (ART/no PGT-A/FET) – 100 patients; group C (ART/no PGT-A/fresh ET) – 346 patients, and group D (NC) – 139 patients. Results: Statistically significant differences among the examined groups were observed for maternal age, BMI, ethnicity, and parity. The median placenta-associated plasma protein (PAPPA) was lowest in the group with ART/PGT-A/FET and the highest result was obtained in the group with ART/no PGT-A/FET. Statistically significant difference in the median PAPP-A levels was identified among the examined groups (p = .0186). When a subgroup analysis was performed, a statistically significant difference was observed in the median PAPP-A between ART/ PGT-A/FET group versus ART/no PGT-A/FET group (p = .01) and NC versus ART/no PGT-A/FET (p = .01). A similar trend toward statistical significance was noted when comparing NC versus ART/no PGT-A/fresh ET (p = .06). Multivariate analysis elucidated that when age is present in the model, the effect of any method of conception or testing for aneuploidy disappears. The other factors (BMI, ethnicity, and parity) do not influence the levels of PAPP-A. The lowest median free human chorionic gonadotropin (b-HCG) was recorded in the NC group and the highest result was identified in the group with IVF/PGT-A/FET. No statistically significant difference was observed in the median concentration levels of free b-hCG among the compared groups (p = .5789) and when subgroup analysis was performed (p>.05). The normality of the distribution of variables was analyzed by the Kolmogorov–Smirnov test and the median PAPP-A and free bhCG concentration difference by the Wilcoxon rank-sum test with nonparametric ANOVA. Conclusions: Testing for aneuploidy (PGT-A) and the decision to transfer either fresh or cryopreserved embryos (ET) appear not to affect the levels of first trimester biochemical markers. The findings of the present study should be a baseline for future studies and could be used to improve the antenatal screening counseling for women with ART pregnancies and PGT-A. [ABSTRACT FROM AUTHOR]

Published
2022
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34. Muskuloskelettale Schmerzen bei Kindern und Jugendlichen -Ein Algorithmus zur differenzialdiagnostischen Abklärung eines onkologischen Leitsymptoms (S2)

Author

TALLEN, G., primary, BIELACK, S., additional, HENZE, G., additional, HORNEFF, G., additional, KORINTHENBERG, R., additional, LAWRENZ, B., additional, NIEHUES, T., additional, PEITZ, J., additional, PLACZEK, R., additional, SCHMITTENBECHER, P., additional, SCHÖNAU, E., additional, WESSEL, L., additional, WIRTH, T., additional, MENTZEL, H.-J., additional, and CREUTZIG, U., additional

Published
2015
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