ANALYSIS OF MENSTRUAL CALENDARS AND SERUM ALPHA(2)-PEG IN WOMEN ON HORMONE REPLACEMENT THERAPY FOR 12 MONTHS

This study was conducted to assess endometrial protection in women on a cyclical combined hormone replacement regimen with 1 mg norethistero ne BP, and to evaluate the use of the bleeding pattern and serum alpha (2)-PEG in monitoring the endometrial response to exogenous hormone th erapy. Fifty-one postmenopausal women attending the Menopause Research Unit at Leicester Royal Infirmary, UK, completed the study. All patie nts were at least 1 year after the menopause, with an average of 26 mo nths since the last menstrual period. All women were prescribed a regi men of two tablets of Hormonin (oestriol 0.27 mg, oestrone 1.4 mg, and oestradiol 0.6 mg) continuously, with 1 mg of norethisterone added fo r 12 days out of each 28-day treatment cycle. Menstrual diaries were c ollected and analysed. The secretory changes were assessed by histolog y, menstrual bleeding pattern and a biological marker of secretory act ivity (alpha(2)-PEG). Withdrawal bleeding occurred on average on days 11, 12, 11, 12 and 13 on months 2, 3, 6, 9 and 12, respectively. There was a poor degree of consistency in the bleeding pattern. The level o f alpha(2)-PEG increased from the average baseline measurement of 2.7 ng/ml (S.D., 4.12) to 8.5 ng/ml (S.D., 4.16) after progestogen treatme nt. This rise, although significant, did not correlate with the uterin e bleeding pattern. There was no statistically significant correlation between the level of alpha 2-PEG and endometrial histology. The findi ngs highlight the fact that cycle predictability on HRT, as exemplifie d in this regimen, is poor. The level of (alpha(2)-PEG is a poor predi ctor of the endometrial histology and has a poor correlation with the day of onset of bleeding.