Nearly half of women involved in work capability benefits tests have attempted suicide, the Commons has heard.
SNP Westminster leader Ian Blackford demanded the assessments, used to decide whether people are eligible to claim support for ill health, be scrapped to mark World Mental Health Day.
Referring to reports in the Independent, Mr Blackford (pictured) also claimed Tory ministers knew about the level of suffering but had not acted to stop it.
Speaking during Prime Minister's Questions, he said: "Nearly one-in-two women taking part in the Government's work capability assessments say they have attempted suicide after or during the process.
"A series of secret internal inquiries into these revealed that Conservative ministers were repeatedly warned of the policy's shortcomings.
"Will the Prime Minister commit today to ensuring her new Minister for Suicide looks at the impact of her government's own social care policies and, at long last, scrap the appalling work capability assessment?"
Theresa May defended the assessments, which she said are used to "encourage" people back into work.
Mrs May started by blaming the previous government for introducing the assessments, to groans and a call of "come on" from the opposition benches.
But, although she stressed she believed assessing claimants in the current manner was the right thing to do, she added it was important staff at the Department for Work and Pensions (DWP) "get these assessments right".
She said: "I think it is right we are encouraging people into the workplace and wanting to ensure those people who are able to be in the workplace are given the support to enable them to do that.
"Of course we look at the impact of those assessments and the quality of those assessments - that is work the DWP does on a regular basis.
"But I think it is important we are undertaking those assessments."
A DWP spokeswoman said suicide was "a very complex issue" and it was "wrong to link it solely to someone's benefit claim".
She said: "Work Capability Assessments were introduced in 2008, and since then we have made significant improvements.
"This includes implementing changes to address issues raised through five independent reviews and strong quality and customer experience improvements.
"A decision on whether someone is able to work is taken following a thorough independent assessment, and after consideration of all the information provided, including supporting evidence from a GP or medical specialist."
Copyright (c) Press Association Ltd. 2018, All Rights Reserved. Picture (c) Jane Barlow / PA Wire.