Comparison of endometrial biopsy and urinary pregnanediol glucuronide concentration in the diagnosis of luteal phase defect

To determine if pregnanediol glucuronide (PG) excretion is useful in luteal phase assessment, we compared daily first morning urinary PG concentrations during the luteal phase in nine normal and nine deficient cycles. Total luteal pregnanediol excretion (44.1 ± 11.3 versus 64.0 ± 11.6 area units ± SEM) was not different. However, significantly less pregnanediol was excreted by the abnormal group during the 1st 5 days of the luteal phase (12.7 ± 1.2 versus 18.0 ± 1.7 area units ± SEM, respectively). Thus, delayed PG excretion may be characteristic of luteal phase defect and measurement of urinary PG may be useful only if daily samples during the early luteal phase are obtained.