The Implications of the Meiotic Spindle Visualization Technique on In Vitro Fertilization (IVF) Outcome in a Perimenopausal Patient

An infertile couple visited an in vitro fertilization center situated in Maharashtra, India, seeking treatment for primary infertility. The 39-year-old premenopausal woman had a history of two intrauterine inseminations and intracytoplasmic sperm injections (ICSI), along with a history of tuberculosis from six years, and a normal hormonal range. The male was normozoospermic. The patient was given a gonadotropin-releasing hormone antagonist treatment and triggered before 36 hours of ovum pickup (OPU), but the cycle failed. Due to normal blood parameters, it was decided to use an optimal microscope using a polarizing filter to check the timing of meiotic spindle (MS) formation in the oocytes. The patient was triggered again for OPU, and during the procedure, 14 oocytes were retrieved. It was decided to perform ICSI after seven and a half hours of OPU post-observation of MS formation around the same hour. On day 21, the patient was suggested for embryo transfer (ET), where two blastocysts (4AA and 3AA) were transferred into the uterus. After a successful ET, the patient was discharged from the hospital. On day 14, a beta-human chronic gonadotrophin report revealed a positive pregnancy (910 mIU/mL).

Morphokinetic parameters using time-lapse technology and day 5 embryo quality: a prospective cohort study

PURPOSE

The aims of this prospective study were to evaluate whether time-lapse parameters can aid in the prediction of day 5 embryo quality and also to assess their discriminatory capacity.

METHODS

In this prospective cohort study, we used time-lapse technology to record specific timings of key events for 380 day 5 blastocysts (originating from 108 patients). Generalized estimating equation regression models were used to evaluate the capacity of these markers to identify a top-quality blastocyst. Multivariable regression models were also constructed, aiming to identify the model with the highest capacity to predict a top-quality blastocyst. The discriminatory capacity of single predictors or composite models was assessed with the use of receiver operating characteristic (ROC) analyses.

RESULTS

Eight significant predictive parameters of a top-quality blastocyst were identified: s3, t6, t7, t8, tM, tSB, tB and tEB. A ROC analysis of the identified parameters found s3 (area under the curve--AUC 0.585, 95 % CI 0.534-0.635) to have the best individual discriminatory capacity to predict a top-quality blastocyst prior to embryo compaction. The parameter tEB (AUC 0.727, 95 % CI 0.675-0.775) was the best predictor regardless of embryo stage. A model containing s3, t8 and tEB showed a slightly increased discriminatory capacity for top-quality blastocyst prediction (AUC 0.748, 95 % CI 0.697-0.794).

CONCLUSIONS

The identified morphokinetic parameters and their cutoffs, albeit of limited clinical value, add to the increasing knowledge concerning the potential predictive markers of a top-quality blastocyst. Additional evidence is necessary before validated time-lapse parameters can be used for embryo selection in IVF laboratories.

Quantification of microfibril angle in secondary cell walls at subcellular resolution by means of polarized light microscopy

The cell walls constitute the mechanical support of plants. Crystalline cellulose building the walls forms rigid microfibrils that set the stiffness of the cell and the direction in which it expands during growth. Therefore, the determination of the directions of the microfibrils is important in both mechanical and developmental assays. We adapted polarized light microscopy to estimate the cellulose microfibril orientations at subcellular resolution. The optical information supplements X-ray scattering data, Raman microspectroscopy, and electron microscopy. We analyzed samples from three plant tissues: cells from an Araucaria excels branch, in which we revealed lower cellulose density in regions where the cell wall curvature becomes bigger, namely, the cell wall corners; a wheat (Triticum turgidum) awn's hygroscopically active region, which revealed a gradient in the cellulose microfibril angles that spans across four cell rows; and a stork's bill's (Erodium gruinum) coiling awn, which revealed that the cellulose in the cell wall is organized in two orientations seamed together, rather than in a continuous helix. The unique spatial information is easily obtained from microscopic specimens and further illuminates new aspects in the mechanical tissues.