This article can be reviewed for FREE on reseachgate.net at https://tinyurl.com/trzw6rj. Check out my typed summary of this episode at otovets.com/cuttingedge.  This summary is best viewed in a browser but is mobile friendly as well. Efficacy of repeatedly used CIDR device in cattle reproduction: a metaanalysis review of progesterone concentration and conception rate Published by Muhammad Furqan Asghar CHACHER, Armağan ÇOLAK, Armağan HAYIRLI Hypothesis: Considerable residual P4 concentration exists in used CIDR (U-CIDR) devices and the achieved blood P4 concentration on days 14–15 after insertion suggests that CIDR devices can be reused upon disinfection in order to minimize the cost of using such a device. Objective: To withdraw conclusions from the available literature regarding P4 concentrations in devices and animals as well as conception rate (CR) responses in cases of multiple U-CIDR devices subjected to various disinfection methods in cattle. Location:  Department of Obstetrics and Gynecology and Department of Animal Nutrition and Nutritional Disorders at Ataturk University Turkey. Methods: Two datasets were compiled from 8 and 7 research articles involving 3434 (2653 heifers + 771 lactating cows + 10 ovariectomized cows) and 7301 cattle (3879 heifers + 3422 lactating cows) to evaluate blood P4 concentration and conception rate, respectively, in response to repeatedly used CIDR devices after sanitization via autoclaving and disinfection. Outcomes: As the number of CIDR usages increased, blood P4 concentration decreased linearly (y = –0.484X + 3.135, R2 = 0.99, P < 0.001). Blood P4 concentration (1.52 vs. 2.20 ng/mL; P < 0.002) and conception rate (40.76 vs. 32.96%, P < 0.05) for lactating cows were lower than those for heifers. The sanitization method did not affect blood P4 concentration, but reused CIDR device subjected to disinfection was associated with reduced conception rate. In summary, depending upon the initial P4 load (1.38–1.90 g), the CIDR device could be used twice in lactating cows and four times in heifers after autoclaving to achieve target blood P4 concentrations.