Previously, the longest amount of time scientists have been able to keep an embryo alive for experimentation was a few days.
Some fertility experts have hailed the development as a breakthrough which will help them prevent miscarriages and improve IVF treatment.
It's prompted calls to extend the legal limit that an embryo can be kept alive and tested on above the current two-week maximum.
Speaking to Premier, James Mildred, from the Christian charity CARE said: "The specific condition of life itself at the moment, and how it's treated by the scientific community at that very early stage, is under real, real threat.
"I would urge caution on this. I would urge greater respect for the dignity of human life. Human life shouldn't be experimented upon in petri dishes in laboratories.
Peter Williams, executive officer for the charity Right to Life has also raised concerns.
Speaking on Premier's News Hour, he said: "I don't believe that you can do an evil thing that good may come of it - that's Romans 3:8.
"Human beings are ends, not means.
"We're destroying human beings, we're destroying people uniquely created and made in the image of God."
Listen to Premier's Aaron James speaking to James Mildred:
Listen to Premier's Antony Bushfield speaking to Peter Williams on the News Hour: