Endocrine parameters and cycle outcome in female patients with low level gonosome mosaicism

Abstract

Objective: Data show there might be an increased number of women with low level gonosome mosaicism in patients, who undergo an ICSI cycle. However, there are only limited data on the question, whether these women have more endocrine problems, or have a worse cycle outcome. To have a sufficient basis for counselling, a retrospective analysis was done. Design: Retrospective, controlled, matched-pair analysis. Materials/Methods: Chromosome analysis is routinely performed in couples with male factor infertility, especially with oligospermia and before ICSI. Women with low level gonosome mosaicism were retrospectively identified by chart review. 22 patients could be identified. As a control group, two controls per case were identified with a normal karyotype, a similiar age, and timepoint of chromosome analysis in the same year as the case. Doing this, 41 appropriate controls could be included. The search for cases and controls was done by collaborators of the Department of Human Genetics, who were not aware of the individual cycle outcomes. Anamnestic data as well as all available cycle data were collected and compared to each other. Statistics were done with Mann Whitney test, and chi-square test as appropriate. Results: Regarding anamnestic data there was no statistically significant difference in cycle length (28.98 +/− 3.10 vs. 30.24 +/− 10.27 days). Also duration of menstrual bleeding, number of previous pregnancies, births or abortions were similiar in cases and controls. The age at menarche was slightly but not significantly higher in cases (13.74 +/− 1.63 vs. 13.12 +/− 1.35 years; p = 0.06). Patients had a similiar age at time of oocyte pick up (33.40 +/− 4.96 vs. 35.26 +/− 4.41 years; p = 0.07). The 22 case patients were treated in 20 IVF or IVF/ICSI cycles. 7 cases did not start treatment. 48 treatment cycles were identified in the control group. 16 patients from the control group did not start any cycle. 16% of patients in the study group and 11% of patients in the control group had oocytes retrieved, but showed total fertilization failure. Regarding the ovarian stimulation the duration of gonadotrophin treatment (13.45 +/− 2.58 vs. 13.09 +/− 2.95 days), the total amount of IU FSH (3856 +/− 2426 vs. 3757 +/− 2167 IU), the estradiol level on the day of oocyte pick-up (2232+/− 1812 vs. 1951+/− 1080 μg/ml), the number of oocytes (9.89 +/− 6.07 vs. 9.74 +/− 5.38 ), as well as the fertilization rate (38% vs. 40%), and the cumulative embryo score (23.88 +/− 15.47 vs. 22.85 +/− 13.43) were not statistically significant different between cases and controls. There was a trend towards a higher pregnancy rate (19% vs. 7%), and towards a higher abortion rate (33% vs. 0%) in the study group, the ongoing pregnancy rate, however, was similiar and not statistically significant different (13% vs. 7%). Conclusions: Regarding endocrine parameters and cycle outcome, patients with low level gonosomal mosaicism can be counselled, that there seems to be no increased risk of cycle cancellation or worse cycle outcome. Oocyte number, fertilization rate, and embryo quality seem to be comparable to an age adjusted control group. Supported by: No support.