Comparing the Absorption of Different Hormone Delivery Systems: A Meta-Analysis

Abstract

Objectives: To create a conversion chart of non-oral estrogen replacement systems based on Cavg. Design: Meta-analysis. Methods: A literature search using two databases, drug manufacturer data, and the online FDA new drug application website was performed in May 2005. Of the original studies identified, those that were selected for analysis met the following inclusion criteria: 1) English in language 2) only included human subjects 3) reported the average blood concentration (Cavg) and 4) were not baseline adjusted. The Cavg data was entered into a spreadsheet and analyzed by an independent statistician. Results: Fifty studies were originally identified. Of these 50 studies, only 22 met inclusion criteria and were used to calculate the mean Cavg of different administration systems. The Cavgs were then used to create a comparison chart. Conclusions: Overall, there has been little research done that examines blood estradiol levels achieved through non-oral administration routes. The chart created from this meta-analysis is vital to health care providers because it allows a patient to be converted from one route to another while assuring the provider that the patient is receiving the same therapeutic benefit.