Effects of malignancies on fertility preservation outcomes and relevant cryobiological advances

Evaluation of the relationship between vitamin D levels with oocyte quality in breast cancer women: a cross-sectional study

Recent evidence suggests that vitamin D deficiency could play an important role in the development of non-skeletal diseases, including cancer. Vitamin D also affects the function of the reproductive system. In the present study, the relationship between 25(OH)D levels with oocyte quality in Breast Cancer (BC) women and control group have been investigated. After initial evaluations, ovarian stimulation began with the GnRH antagonist protocol in the BC group (N = 16) and control group (N = 16). The serum and follicular fluid (FF) 25(OH)D levels were measured at the time of oocyte retrieval and their relationship to oocyte quality was examined. The mean levels of serum and FF 25(OH)D in BC women were significantly lower than in the control group (22.26 ± 7.98 vs. 29.61 ± 9.12, P = 0.02, 21.65 ± 7.59 vs. 28.00 ± 9.05, P = 0.04, respectively). There was a significant correlation between the levels of 25(OH)D in FF and serum in BC women (r = 0.873, P < 0.001). But there was no correlation between the serum or FF 25(OH)D levels with the parameters related to oocytes (P > 0.05). In the BC women, the number of dysmorph and highly dysmorph oocytes was higher than in the control group (P < 0.001). Women with BC referring to infertility centers for fertility preservation are more likely to be deficient in serum 25(OH)D level; this subsequently affects the FF 25(OH)D level. However, serum and FF 25(OH)D levels may not be suitable indicators for examining maturity and quality of oocytes in terms of morphology in BC women, and the poor morphological quality of oocytes in BC women may be due to other factors.

Ru360 protects against vitrification-induced oocyte meiotic defects by restoring mitochondrial function

Oocyte vitrification has been widely application in female fertility preservation. Recent studies found that vitrification of immature (germinal vesicle stage, GV) oocytes increased the risk of aneuploidy during meiotic maturation; however, the underlying mechanisms and the strategies to prevent this defect remain unexplored. In this study, we found that vitrification of GV oocytes decreased the first polarbody extrusion rate (90.51 ± 1.04% vs. 63.89 ± 1.39%, p < 0.05) and increased the aneuploid rate (2.50% vs. 20.00%, p < 0.05), accompanied with a series of defects during meiotic maturation, including aberrant spindle morphology, chromosome misalignment, incorrect Kinetochore-Microtubule attachments (KT-MTs) and weakened spindle assembly checkpoint protein complex (SAC) function. We also found that vitrification disrupted mitochondrial function by increasing mitochondrial Ca²⁺ levels. Importantly, inhibition of mitochondrial Ca²⁺ entry by 1 μM Ru360 significantly restored mitochondrial function and rescued the meiotic defects, indicating that the increase of mitochondrial Ca²⁺, at least, was a cause of meiotic defects in vitrified oocytes. These results shed light on the molecular mechanisms of oocyte vitrification-induced adverse effects of meiotic maturation and provided a potential strategy to improve oocyte cryopreservation protocols further.

Fertility after Cancer: Risks and Successes

The incidence of cancer in reproductive-aged women is 7%, but, despite the increased number of cancer cases, advances in early diagnosis and treatment have raised the survival rate. Furthermore, in the last four decades, there has been a rising trend of delaying childbearing. There has been an increasing number of couples referred to Reproductive Medicine Centers for infertility problems after one partner has been treated for cancer. In these cases, the main cause of reduced fertility derives from treatments. In this review, we describe the effects and the risks of chemotherapy, radiotherapy, and surgery in women with cancer, and we will focus on available fertility preservation techniques and their efficacy in terms of success in pregnancy and live birth rates.

A Survey Study Reveals the Positive Impact of Oncofertility Knowledge and Attitude on Oncofertility Practice Among Oncologists in China

Purpose: The advances of early cancer diagnoses and treatment methods allow many adolescent and young adult-aged cancer patients to live long lives after having cancer. There is a rising concern regarding cancer treatment-induced reproductive toxicities and infertility. Oncologists are the first line of medical professionals interacting with cancer patients and playing essential roles in oncofertility practice. This study aimed to assess the oncofertility knowledge, attitude, and practice of oncologists in China. Methods: We created an online questionnaire survey to examine 927 Chinese oncologists' demographics, knowledge, attitude, experience, and practice regarding young female cancer patients' infertility risk and fertility preservation. Results: Results showed that there is an inadequate oncofertility knowledge among surveyed oncologists, which was affected by oncologists' demographic background of education level, clinical title, and working experience. The majority of surveyed oncologists (84.8%-88.7%) held a positive attitude on young female cancer patients' infertility risk and their fertility preservation demand, but their attitude was impacted by marriage status and patients risk of cancer recurrence. Only 11.8% of surveyed oncologists often referred their patients for fertility preservation, while 66.3% and 21.9% of them have referred once or never, respectively. The oncologists' oncofertility practice was not correlated with their demographic background but was significantly influenced by their oncofertility knowledge and attitude. Conclusion: Our study demonstrates that there is an urgent unmet need to improve oncologists' oncofertility knowledge, attitude, and practice in China as well as remove the communication barrier between oncologists and fertility specialists.