Intra‐follicular kisspeptin levels are related to oocyte maturation and gonadal hormones in patients who are undergoing assisted reproductive technology

PURPOSE: To assess the kisspeptin concentrations in follicular fluid and their relationship with clinical outcomes during assisted reproductive technology. METHODS: Thirty‐nine patients who were aged 24‐40 years and underwent oocyte retrieval for in vitro fertilization/intracytoplasmic sperm injection participated in this study. In 65 follicular fluid samples that had been obtained from 30 patients and their blood samples, the kisspeptin levels were measured in order to investigate the correlations with their gonadal hormone levels. Venous blood samples were collected from 14 patients to investigate their plasma kisspeptin levels across different phases of assisted reproductive technology. RESULTS: The follicular fluid kisspeptin level was significantly higher than that of the plasma level and was positively associated with the follicular fluid estradiol concentration and with the serum estradiol and number of mature oocytes. In the plasma, the maximum concentration of kisspeptin was observed on the day of ovum pick‐up and on the day of embryo transfer during ovarian stimulation for assisted reproductive technology. CONCLUSION: Kisspeptin was present in the follicular fluid and the plasma kisspeptin concentration was affected by ovarian stimulation. Kisspeptin appears to affect oocyte maturation and ovulation.