Reeve said his friend "started to look a little pale" and became upset and anxious.
He described the glass as thin, like "old lightbulb glass".
Reeve told the Herald: "I was worried about my friend, it scared the living daylights out of me."
They returned to the store, where staff offered them a refund, which they accepted, and some replacement strawberries, which the pair turned down.
The pair sought treatment for Reeve's friend at the Accident & Medical Clinic at nearby Kenepuru Hospital, where Reeve says a doctor told his friend to drink a fizzy drink and eat some bread to dislodge the glass and help it to pass through her system.
Reeve told the Herald that Pak'nSave offered to pay for their visit to the clinic.
He said that when they returned to Pak'nSave after the hospital visit, the strawberries had been removed from sale.
Reeve said that two other people have contacted him since he went public, saying they had similar experiences.
A spokesperson from Foodstuffs, which operates Pak'nSave, told the Herald: "We are aware of an isolated incident involving strawberries at one of our stores. We can confirm that we have secured and removed all contaminated product from the store.
"This incident is isolated to this particular store and has no impact on similar product at other stores.
"We are currently working closely with our store, the supplier and MPI in investigating the situation and have no further comment to make at this time."
A spokesperson for MPI confirmed to the Herald that the contamination happened in-store: " We have been made aware that glass fragments have been found in a punnet of strawberries purchased from Pak'N Save Porirua. We've confirmed the issue is isolated to this store and is associated with a broken light fitting in the store's walk-in produce chiller.
"The safety and wellbeing of consumers is our number one priority and we are looking into the matter to determine if there is any further risk to the public. If there is, we will take action, including a possible recall."
