OBJECTIVE: We have described distinctions in urinary reproductive hormone in young infertile DOR patients (reflected by Day 3 serum FSH >10mIU/ml & poor response to ovarian stimulation) compared to healthy controls. The current study was aimed at assessing if hormone profiles in DOR patients are similar to those seen with natural aging. DESIGN: Prospective observational study. MATERIALS AND METHODS: Gonadotropins (FSH & LH), and metabolites of estrogen & progesterone (E1c & Pdg) were assessed in daily urine samples collected in an unstimulated menstrual cycle in 8 DOR patients (aged 32-37) & in 12 perimenopausal women (aged 43-52). A Pdg algorithm was used to confirm the ovulatory status. Area under the curve (AUC) was estimated for each hormone and comparisons were made between the two groups using student's t test. RESULTS: Distinct differences in hormone profiles were observed between DOR patients and older perimenopausal women. Both the amplitude & duration of the LH surge were more pronounced in DOR vs. perimenopausal women. DOR patients had significantly lower early follicular phase FSH & lower whole-cycle E1c.Tabled 1Hormonal comparisons between DOR & perimenopausal womenPerimenopausalDORControlsFSH of Day -14 to -7 (mU/mgCr)26 ± 2.87.48 ± 0.66‡6.23 ± 0.33∗These numbers are included for references. No comparison done with the other groups.LH peak amp (mU/mgCr)32 ± 7.7564 ± 1641 ± 7.87∗These numbers are included for references. No comparison done with the other groups.LH surge duration (days)1.42 ± 0.153.25 ± 0.45‡p<0.05 when compared with perimenopausal data.1.93 ± 0.24∗These numbers are included for references. No comparison done with the other groups.E1c AUC (ng/mgCr)1646 ± 296654 ± 104‡p<0.05 when compared with perimenopausal data.1054 ± 83∗These numbers are included for references. No comparison done with the other groups.Pdg AUC (ug/mgCr)75 ± 1255 ± 11.5116 ± 19.4∗These numbers are included for references. No comparison done with the other groups.∗ These numbers are included for references. No comparison done with the other groups.‡ p<0.05 when compared with perimenopausal data. Open table in a new tab Luteal Pdg levels were similar in both groups. CONCLUSIONS: Despite having low ovarian reserve, women with DOR had lower FSH, lower E1c and a more robust LH surge than older perimenopausal women. These data suggest that DOR is a distinct entity in the paradigm of reproductive senescence. Age may mitigate the hormonal manifestations of ovarian follicular depletion.