Relationship of reactive oxygen species levels in day 3 culture media to the outcome of in vitro fertilization/intracytoplasmic sperm injection cycles.

OBJECTIVE: To examine the relationship of early human embryonic development parameters to day 3 reactive oxygen species (D-3 ROS) levels in culture media.
DESIGN: Prospective study.
SETTING: Tertiary care hospital. PATIENT(S): Patients were undergoing IVF (n=92; 36 with intracytoplasmic sperm injection [ICSI]). INTERVENTION(S): The D-3 ROS levels in sample and control of each embryo culture dish were measured by the chemiluminescence method using a luminol probe. MAIN OUTCOME MEASURE(S): Embryo quality (days 3 and 5) and pregnancy rates (PR). RESULT(S): The D-3 ROS level was significantly lower in pregnant cycles 26.8±13.9×10(6) cpm (counted photon per minute) versus nonpregnant cycles 66.4±39.4×10(6) cpm. This relationship was maintained when the cycles were stratified to conventional IVF (27.1±14.95 vs. 67.0±39.9×10(6) cpm) or ICSI (25.6±12.75 vs. 65.5±39.7×10(6) cpm). After controlling for all variables, D-3 ROS levels were negatively correlated with blastocyst development rate as well as PR. Odds ratio (OR) (95% confidence interval [CI]) of clinical pregnancy corresponding to a 10×10(6) cpm increase in D-3 ROS was 0.47 (0.30-0.74) for ICSI and 0.56 (0.37-0.85) for IVF. CONCLUSION(S): During extended in vitro culture, ROS generated in culture media by day 3 may be an important biochemical marker for blastulation. An increase of 10 units in D-3 ROS may decrease the clinical pregnancy by 41%.