Agata Sojecki

Is the zona pellucida thickness of human embryos influenced by women's age and hormonal levels?

OBJECTIVE To evaluate whether zona pellucida thickness (ZPT) of human embryos is correlated with maternal age, patients hormonal status, embryo quality, and IVF outcomes. DESIGN Prospective study. SETTING University-affiliated IVF clinic. PATIENT(S) Couples undergoing IVF-ET cycles. INTERVENTION(S) Zona measurements, clinical data collection. MAIN OUTCOME MEASURE(S) Correlation between the ZPT and maternal age, basal FSH and E(2) levels, stimulation protocols, cause of infertility, embryo quality, and implantation/pregnancy rates. RESULT(S) The measurements of ZPT were collected from 5,184 day 3 human embryos originated from 744 IVF patients. The overall mean ZPT was 16.18 ± 2.00 μm. No significant correlation was observed between the ZPT and the patients age, E(2) values on the day of hCG administration, basal concentration of serum FSH, stimulation protocol, infertility diagnosis, and implantation/pregnancy rates. The ZPT was strongly influenced only by the embryo quality: Embryos with good morphology exhibited considerably thinner ZP compared with those of less favorable morphology (mean 15.87 ± 2.48 μm vs. 16.36 ± 2.57 μm, respectively). The ZPT had no significant impact on the implantation and pregnancy rates. CONCLUSION(S) The thickness of the human ZP of day 3 embryos is not influenced by womens age and hormonal levels. The strong correlation between ZPT and embryo quality suggests that thickness of ZP depends on inherent embryo properties. The overall ZPT is not a good predictive indicator for IVF clinical outcomes.

Laser zona thinning in women aged ≤37 years: a randomized study

The objective of this prospective randomized double-blind clinical trial was to evaluate whether laser zona pellucida thinning of human embryos improves clinical outcomes in women <or=37 years old undergoing IVF-ET treatment. The study did not reveal any significant beneficial effect of laser zona thinning on clinical pregnancy (16 out of 45 vs. 18 out of 39) and live birth rates (13 out of 45 vs. 16 out of 39) between the laser-treated and nontreated groups of patients, although there was a trend toward an increased incidence of dichorionic multiple pregnancies in the study group compared with the control group (7 out of 13 vs. 4 out of 16).

Comparison of IVF Outcomes between Minimal Stimulation and High-Dose Stimulation for Patients with Poor Ovarian Reserve.

We examined whether treatment with minimum-dose stimulation (MS) protocol enhances clinical pregnancy rates compared to high-dose stimulation (HS) protocol. A retrospective cohort study was performed comparing IVF and pregnancy outcomes between MS and HS gonadotropin-antagonist protocol for patients with poor ovarian reserve (POR). Inclusion criteria included patients with an anti-Müllerian hormone (AMH) ≤8 pmol/L and/or antral follicle count (AFC) ≤5 on days 2-3 of the cycle. Patients from 2008 exclusively had a HS protocol treatment, while patients in 2010 had treatment with a MS protocol exclusively. The MS protocol involved letrozole at 2.5 mg over 5 days, starting from day 2, overlapping with gonadotropins, starting from the third day of letrozole at 150 units daily. GnRH antagonist was introduced once one or more follicles reached 14 mm or larger. The HS group received gonadotropins (≥300 IU/day) throughout their antagonist cycle. Clinical pregnancy rate was significantly higher in the MS protocol compared to the HS protocol (P = 0.007). Furthermore, the live birth rate was significantly higher in the MS group compare to the HS group (P = 0.034). In conclusion, the MS IVF protocol is less expensive (lower gonadotropin dosage) and resulted in a higher clinical pregnancy rate and live birth rate than a HS protocol for poor responders.

Morphologic and cytogenetic analysis of human giant oocytes and giant embryos.

BACKGROUND Giant binuclear oocytes occur with considerable frequency in human ovaries, but their ultimate fate remains unknown. We report the morphology, cytogenetics and developmental potential of human giant oocytes from patients undergoing assisted reproductive technologies. METHODS AND RESULTS A total of 44 giant oocytes was collected from patients aged 22-44 years old, with an overall frequency of 0.3% (44/14 272 oocytes). Giant oocytes were approximately 30% larger in diameter than normal oocytes (mean 200.4 versus 154.7 micro m, P = 0.0001). Two different morphological patterns were observed among giant unfertilized and fertilized oocytes. All unfertilized oocytes appeared to be diploid and contained either one or two metaphase plates (46 or 2 x 23 chromosomes), and one or two polar bodies respectively. Consequently, fertilized giant oocytes exhibited either two or three pronuclei, or two or four polar bodies. Both types of giant zygotes were capable of normal cleavage and development to blastocyst stage. Four giant embryos were analysed by interphase fluorescence in-situ hybridization using probes for chromosomes 9, 22, X and Y, and all appeared chromosomally abnormal with numerical alterations indicative of ploidy change. CONCLUSIONS Giant oocytes might be a possible source of human digynic triploidy. To avoid undesired miscarriages, giant embryos originated from either two- or three-pronuclear giant zygotes should be excluded from uterine transfers.