Registry · media · Vitrolife
G-1 PLUS / G-2 PLUS (sequential culture)
Two-step sequential media: G-1 for day 1–3 cleavage culture, G-2 for day 3–5/6 blastocyst culture.
What it is and how it's used
Embryos are moved from G-1 to G-2 on day 3. Both are bicarbonate-buffered and used under oil. The changeover is a handling step with its own risks (time out, temperature, pH).
Typical failure modes
- Blastocyst rate falls after a G-2 lot change while fertilisation stays normal.
- Slow/arrested embryos when the day-3 changeover is prolonged or done on a cool stage.
- Excess embryos per drop or very small drops altering development in some labs.
What to check first
- Lot dates for G-1 and G-2 versus the KPI change; storage log.
- Day-3 changeover: minutes out of the incubator, stage temperature by probe, dish equilibration.
- Compare blastocyst rate by incubator to separate medium from incubator effects.
IFU and practice notes
Follow the IFU for equilibration, overlay, and shelf life. Record every lot change in the lab lot log.
Neutral, and the IFU wins
This page summarises common experience across labs and is not manufacturer guidance. Always follow the current instructions for use for the exact product and version you have, and validate any change of product or protocol before patient use. Corrections and additions are welcome — tell us.
Shared with you by your clinic · Source: https://embryologics.com/embryologists/registry/vitrolife-g1-g2 · Medical Interventions. Reviewed by a certified clinical embryologist. Educational information — please discuss your own situation with your clinic.
This page is educational and general. It is not a substitute for advice from your own clinic or the manufacturer's instructions for use.