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Objective: To measure antioxidant enzyme activities and lipid peroxidation levels within follicular fluid (FF) and evaluate correlations with early embryo quality., Design: Individual FF samples were obtained prospectively on the day of oocyte collection and assessed for lipid peroxidation as specific positional isomers of hydroperoxy and hydroxy fatty acids by high-performance liquid chromatography and antioxidant enzyme activities by automated kinetic enzyme assays. Spearman rank correlation coefficients, adjusted for age and day of transfer, were used to assess associations between antioxidant enzymes and lipid peroxidation products and embryo quality using a 1 follicle-1 oocyte/embryo approach. Post hoc power analysis was conducted to help interpret null results., Setting: A university clinic., Patient(s): Thirty-nine women undergoing IVF., Intervention(s): None., Main Outcome Measure(s): Embryo cell number and embryo fragmentation score (EFS) at transfer., Result(s): No significant correlations between lipid peroxidation derivatives or antioxidant enzyme activities and embryo quality were obtained. Post hoc power analysis indicated possible undetected associations between EFS and 13-hydroxy octadecatrienoic acid and 13-hydroperoxy octadecadieneoic acid., Conclusion(s): Our preliminary dataset suggests that most lipid peroxidation products and antioxidant enzyme activities within FF are not associated with the quality of embryos, using EFS and embryo cell number as end points. However, further consideration of associations between EFS and 13-hydroxy octadecatrienoic acid and 13-hydroperoxy octadecadieneoic acid is warranted., (Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Here we assess bisphenol A (BPA) in couples undergoing in vitro fertilization (IVF) and indicators of embryo quality; embryo cell number (ECN) and embryo fragmentation score (EFS). Twenty-seven couples provided serum on the day of oocyte retrieval. Unconjugated BPA was measured by HPLC with Coularray detection. Odds ratios (OR) were generated using ordinal logistic regression including female and male BPA concentrations, age and race, and day of embryo transfer for ECN. Inverse associations are suggested for male BPA with ECN (OR=0.70, P=0.069), and EFS (OR=0.54, P=0.009), but not for women. Male BPA exposure may affect embryo quality during IVF., (Copyright © 2011 Elsevier B.V. All rights reserved.)

This narrative review summarizes the current state of knowledge about human embryo fragmentation during IVF. The clinical relevance of fragmentation is discussed and evidence supporting a central role for the oocyte in the pathogenesis of fragmentation is presented. A mechanism of fragmentation as aberrant cell division involving the cytoskeleton is described along with the novel concept of membrane instability in relation to follicular high-density lipoprotein metabolism and cholesterol transport., (Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Trace exposures to the toxic metals mercury (Hg), cadmium (Cd) and lead (Pb) may interfere with in vitro fertilization (IVF). The aim of this study is to explore biologically plausible hypotheses concerning associations between metals and embryo quality indicators during IVF. For 24 female patients, a multivariable ordinal logistic regression model suggests a 75% reduction in the odds for higher embryo cell cleavage per μg/dL increase in blood Pb (adjusted odds ratio (aOR) 0.25, 95% confidence interval (CI) 0.07-0.86). For 15 male partners, each μg/L increase in blood Hg (aOR 0.60, 95% CI 0.45-0.79) and μg/dL increase in blood Pb (aOR 0.58, 95% CI 0.37-0.91) is associated with a decrease in the analogous odds. Embryo fragmentation is reduced by higher blood Hg (aOR 0.85, 95% CI 0.72-1.00), but increased by higher blood Pb (aOR 1.47, 95% CI 1.11-1.94) in men. The magnitude of these suggested effects warrants confirmation in a larger study., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Background: High-density lipoprotein (HDL) appears to be the dominant lipoprotein particle in human follicular fluid (FF). The reported anti-atherogenic properties of HDL have been attributed in part to reverse cholesterol transport. The discoveries of the scavenger receptor class B type I (SR-BI) and the ATP-binding cassette A1 lipid (ABCA1) transporter have generated studies aimed at unraveling the pathways of HDL biogenesis, remodeling and catabolism. The production of SR-BI and ABCA1 knockout mice as well as other lipoprotein metabolism-associated mutants has resulted in reduced or absent fertility, leading us to postulate the existence of a human hepatic-ovarian HDL-associated axis of fertility. Here, we review an evolving literature on the role of HDL metabolism on mammalian fertility and oocyte development., Methods: An extensive online search was conducted of published articles relevant to the section topics discussed. All relevant English language articles contained in Pubmed/Medline, with no specific time frame for publication, were considered for this narrative review. Cardiovascular literature was highly cited due to the wealth of relevant knowledge on HDL metabolism, and the dearth thereof in the reproductive field., Results: Various vertebrate models demonstrate a role for HDL in embryo development and fertility. In our clinical studies, FF levels of HDL cholesterol and apolipoprotein AI levels were negatively associated with embryo fragmentation, but not with embryo cell cleavage rate. However, the HDL component, paraoxonase 1 arylesterase activity, was positively associated with embryo cell cleavage rate., Conclusions: HDL contributes to intra-follicular cholesterol homeostasis which appears to be important for successful oocyte and embryo development.

Purpose: To investigate whether follicular fluid lipid-soluble micronutrients are associated with embryo morphology parameters during IVF., Methods: Follicle fluid and oocytes were obtained prospectively from 81 women. Embryo morphology parameters were used as surrogate markers of oocyte health. HDL lipids and lipid-soluble micronutrients were analyzed by high-pressure liquid chromatography. Non-parametric bi-variate analysis and multivariable ordinal logistic regression models were employed to examine associations between biochemical and embryo morphology parameters., Results: Follicular fluid HDL cholesterol (r = -0.47, p < 0.01), alpha-tocopherol (r = -0.41, p < 0.01), delta-tocopherol (r = -0.38, p < 0.05) and beta-cryptoxanthine (r = -0.42, p < 0.01) are negatively correlated with embryo fragmentation. Ordinal logistic regression models indicate that a 0.1 mumol/L increase in beta-cryptoxanthine, adjusted for gamma-tocopherol, is associated with a 75% decrease in the cumulative odds of higher embryo fragmentation (p = 0.010)., Conclusion: Follicular fluid HDL micronutrients may play an important role in the development of the human oocyte as evident by embryo fragmentation during IVF.

Background: High-density lipoprotein (HDL) is the sole lipoprotein present in follicular fluid (FF). The objectives of this study were to examine HDL lipid composition and associated enzyme activities in FF and serum and to relate these levels to embryo morphology parameters in women undergoing in vitro fertilization (IVF)., Methods: Serum and FF were prospectively obtained from 60 women undergoing IVF. HDL lipids, apolipoprotein AI (ApoAI), paraoxonase 1 (PON1) and paraoxonase 3 (PON3) activities were determined. Bivariate analysis and ordinal logistic regression models were employed to examine the associations between biochemical measures and embryo morphology parameters [embryo cell number (ECN) and embryo fragmentation score (EFS)] as surrogate markers of oocyte health., Results: All biochemical parameters were significantly (P < 0.05) lower in FF than serum except PON3 levels which were significantly higher. FF-HDL cholesterol (OR 0.66, 95%CI 0.46-0.96) and ApoAI (OR 0.13, 95%CI 0.03-0.97) levels were negative predictors for EFS; however, their effects were not independent and the level of one moderated the effect of the other. Limited to Day 3 embryo transfers, FF-PON1-arylesterase activity was a significant positive predictor for ECN (OR 1.09, 95%CI 1.01-1.17)., Conclusions: In this pilot study, our data suggests that HDL and its component proteins within FF may play protective roles in the health of the human oocyte and subsequent early embryo development. We describe for the first time the activities of PON1 and PON3 in FF. We suspect that PON3 activity may be locally generated due to higher activities in FF compared with serum.