Spectrophotometric absorbance of follicular fluid: a selection criterion

The aim of this study was to ascertain the absorbance profiles of uncontaminated follicular fluids (FF) vs blood and medium contaminated FF, and to test the hypothesis that blood contamination alters the biochemical status of FF.

FF (n = 655) from 230 patients were scanned spectrophotometrically during an ongoing in vitro fertilization (IVF) program. Based on spectrophotometric evaluation, blood contaminated and uncontaminated FF (n = 39 patients/FF) were analyzed for electrolyte content, inorganic phosphate, glucose, creatine, urate, total protein, albumin, bilirubin, cholesterol, alkaline phosphatase, gamma-glutamyltransferase, alanine aminotransferase, aspartate transaminase, and lactate dehydrogenase by means of a SMAC analyzer.

Laparoscopic aspiration resulted in the collection of significantly more clear FF compared to the transvaginal procedure (P = 0.001). Uncontaminated fluid depicted a single mean absorbance at 458.0 nm. Blood contaminated FF could be identified by spectrophotometry and revealed three peaks at 418.12, 540.13, and 575.32 nm, respectively, according to the degree of blood contamination. Follicular fluid diluted with Earles Balanced Salt Solution (EBSS) displayed an additional mean peak at 561.4 nm. Potassium, glucose, and all of the above mentioned enzymes revealed significantly higher levels in blood contaminated FF (P < 0.05).

From this study, it is concluded that blood contamination and dilution with culture medium influence the biochemical composition as well as the absorbance spectrum of follicular fluids. This procedure is advocated as a prerequisite before quantifying FF content.