04/29/2026
Is using a high lactate fertilization medium putting undue stress on your lab?
Exposure to elevated lactate levels prior to day 1 introduces metabolic stress at a time when embryos are most vulnerable, and in a way that later culture interventions cannot fully compensate for.
Clinical studies show that exposure to low-lactate culture from retrieval is associated with measurable improvements in embryo development and clinical outcomes, including:
• Higher Day 5 & Day 6 blastocyst utilization, even after adjusting for patient age*
• Increased utilization in patients over 38†
• Higher euploidy rates compared with CSCM‡
• Improved clinical pregnancy rates with reduced miscarriage§
• Reduced embryo discard rates**
CSCM-NX can be used immediately following retrieval and has the lowest-lactate formulation (1mM), aligned with early embryo metabolism.
References:
* Benini F, Watson L, Dusini S, A Degl”Innocenti, Adversi F, Cammunci S, Di Biase L, F Bertini, Benvenuti M. A low-lactate undisturbed culture medium protocol provides an increase in usable blastocysts on day 5 vs. day 6. Human Reproduction. 2022;37(1). deac107.254
Manzo R, Listorti I, Colasante A, Scarselli F, Greco P, Arrivi C, Watson L, Greco A, Varricchio M.T., Pirastu G, Musella M, Barberi M, Uva D, Pristera’ A, Greco E. A continuous culture medium with a lower concentration of lactate has a pronounced effect on the percentage of usable blastocysts on day 5. Human Reproduction. 2022;37(1). deac107.256
† Hammond E, Morbeck D. Reducing the stress of culture? Low lactate embryo culture medium increases usable blastocyst rate for women of advanced maternal age. Fertility and Sterility. 2020;114(3); e7-e7
‡ Whitney JB, Watson L, Maizar A, VerMilyea M. Positive effects of low-lactate culture medium on embryo development and blastocyst ploidy status: a 3.5-year multi-clinic retrospective review. Human Reproduction. 2022; 37 (1). deac107.217
§ Kobanawa M. Fertilization, embryo culture, and clinical results using low lactate embryo culture medium for pre-culture, insemination, and beyond. Reprod Med Biol. 2022;21(1):e12458. doi:10.1002/rmb2.12458
** Moreno Moya JM, Mansell S, Alland I, Øverlie I, Sørdal T, Finset M. CSCM-NXC media containing a low lactate concentration seems to benefit expansion grade compared to traditional continuous media. Human Reproduction. 2022; 37(1), deac104.080