Channel 4 has said "very serious allegations of wrongdoing" have been made against a small number of past Married At First Sight UK contributors.
The broadcaster said it had removed all previous seasons of MAFS UK from its streaming platforms.
The move follows an external review, commissioned by the broadcaster in April, into the welfare of participants on the programme.
The BBC has reported allegations from two women who alleged they were raped during filming of the show. A third described an allegation of a non-consensual sex act.
They all alleged the show did not do enough to protect them.
In a statement on Monday, Channel 4 said: "In April, Channel 4 was presented with serious allegations of wrongdoing against a small number of past contributors, allegations that we understand those contributors have denied.
"The channel is mindful of the privacy and continuing duty of care towards all contributors, and cannot comment on or disclose details of those allegations.
"Related to those allegations, Channel 4 was asked to respond to claims of failures in welfare protocols. Channel 4 believes that when concerns related to contributor welfare were raised through existing welfare and production protocols, prompt and appropriate action was taken, based on the information available at the time.
"Channel 4 strongly refutes any claim to the contrary."
Priya Dogra, chief executive of Channel 4, said: "I want to express my sympathy to contributors who have clearly been distressed after taking part in Married At First Sight UK. The wellbeing of our contributors is always of paramount importance.
"It would be wholly inappropriate for me to comment on what are very serious allegations made against some MAFS UK contributors.
"Those allegations - which I understand are disputed by the contributors accused - are not something that Channel 4 is in a position to adjudicate on.
"We are also mindful of our ongoing duty of care to all contributors, and the need to preserve the anonymity and privacy of all involved.
"On the claims that Channel 4 may have failed in its duty of care, I believe that when concerns about contributor welfare were raised, and based on the information available at the time, Channel 4 acted quickly, appropriately, sensitively and with wellbeing front and centre."
The show, which is produced for Channel 4 by independent production company CPL, sees single people matched by experts to "marry" strangers who they meet for the first time on their wedding day.
Sky News has contacted CPL for comment.
(c) Sky News 2026: Channel 4 says 'very serious' claims of wrongdoing made against past Married At First Sight
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