The Effect of Media Type, Gas Environment, and Incubator Model on IVF Success Rates

Abstract

Objective: To optimize ongoing clinical pregnancy rates in an unselected IVF population, we retrospectively compared two different media formulations (P1/G1/G2 sequential and LifeGlobal medium), contrasted a 6% CO2 in air with a 6% CO2/5% O2/89% N2 gas incubator environment, and finally evaluated the effectiveness of two different types of incubators (Sanyo MCO-5M vs. Hearus 240). Over a 1-year period between April 2006 and March 2007, treatments were applied in quarterly increments. Methods: All patients experienced controlled ovarian hyperstimulation, followed by egg retrieval 35 h after hCG. Eggs were recovered and placed in P1 medium + 5% HSA until insemination. Eggs were moved to a more complex medium containing 5% HSA/5% SS after ICSI or after IVF fertilization check. Embryos were evaluated on day 3 and transfered on day 3 to 5 depending on the number/quality of embryos available and the IVF history of the patient. Transfers were performed under ultrasound guidance, primarily using a Wallace catheter. Results: Tabled 1Age <35 yr + donor cyclesAge <38 yr + donorsCategorynn (%) + b-hCGn (%) OngPregnn (%) + b-hCGn (%) OngPreg6% CO2/air incubation[2ndQrt06]P1/G1/G2 media4940 (82)aSignificant difference (P<.05) within column subsection.31 (63)aSignificant difference (P<.05) within column subsection.7554 (72)42 (56)[4thQrt06]Global medium4929 (59)24 (49)6542 (65)33 (51)6% CO2/5% O2/90% N2 incubation[1stQrt07]Sanyo Mini2922 (76)21 (72)aSignificant difference (P<.05) within column subsection.3825 (66)24 (63)[LG media]Heraeus 2402115 (71)13 (62)3224 (75)aSignificant difference (P<.05) within column subsection.20 (63)Combined TG5037 (74)34 (68)7049 (70)44 (63a Significant difference (P<.05) within column subsection. Open table in a new tab Conclusions: Overall, both the P1/G1/G2 sequential system and the LG all-in-one medium produced good pregnancy rates under standard 6% CO2 in air conditions. In contrast, the LG system with tri-gas incubation significantly improved pregnancy outcomes by reducing SABs and biochemical pregnancies (50% decrease), resulting in higher ongoing clinical pregnancy rates. No difference was observed in the type of incubator used; however, this is one of the first reports validating the clinical effectiveness of the new Sanyo mini-incubators.