P-725: Correlation of antimullerian hormone levels with primordial follicle count in human ovary

Abstract

Previous studies indicated the anti mullerian hormone (AMH) is expressed in preantral follicles and it might be a marker of ovarian reserve. However, there is no direct evidence tying AMH production to primordial follicles in humans. In the human ovary, AMH expression begins at 36 weeks of gestation. Our objective was to investigate if AMH levels directly correlate with primordial follicle numbers in human adult ovarian tissue using an in vitro model. In vitro investigation of AMH production from adult ovarian cortical pieces and fetal ovarian tissue Ovarian cortical pieces from 9 cancer patients undergoing ovarian cryopreservation for fertility preservation and human fetal ovarian tissue from abortuses of 24 weeks gestation were included in the study. 2x2 mm fetal and 5x5 mm adult ovarian pieces were either fixed, paraffin embedded, and serially sectioned to determine baseline follicle density (primordial follicle/mm2) on every fifth section, or cultured in alpha-MEM medium supplemented with 20 % fetal bovine serum and 300-mIU/mL recombinant FSH for seven days. Half of the culture medium was removed every day and stored at - 80 0C until assayed for AMH levels by ELISA. Primordial follicle density was re-evaluated after the 7-day culture. Primordial follicle density was determined as the mean of follicle counts/mm2 in every fifth section. Mean ± [SE] age of the adult patients from whom the tissues were obtained was 27.5 ± 2.7 (range 18-36). The mean primordial follicle density at baseline and after culture was 29.5 ± 3.1 and 3.12 ± 1.3 in fetal ovaries, and 9.31 ± 2.6 and 5.83 ± 2.1 in adult patients, respectively. There were no growing follicles in fetal ovarian tissue before and after culture. In adult tissue 98.2% of follicles were at primordial stage before culture but no growing follicles were seen after the 7-day culture period. In fetal ovarian tissue, 100% of follicles were in primordial stage before and after culture. As expected, AMH was undetectable in fetal ovarian cultures. In adult ovarian tissue cultures, both AMH level on culture day 7 and age correlated with post-culture follicle counts (p<0.01, Fig-1). We provided the first evidence linking the in vitro AMH production to primordial follicle density in human ovarian tissue.