Pregnant Labour MPs or those on maternity leave should be automatically reselected as a candidate in the next election, says a former deputy leader.
Harriet Harman warned of a “justified outcry” if an MP going through the selection process miscarried.
Members can trigger a vote if they don’t want their current MP to run as their candidate in a general election.
Some Labour MPs have been threatened with deselection, including Ellie Reeves who is five months pregnant.
In a letter to her party’s National Executive Committee, Ms Harman said it was important for party members to have a say but added “accountability is in conflict with the principles of how we expected pregnant woman and new mothers to be treated”.
Calling for such MPs to be automatically reselected, she said: “Many thousands of women face pregnancy or maternity discrimination every year and we have to be their champions.
“If we don’t automatically reselect pregnant/new mother women MPs, they will have to go through the reselection process,” she said.
She said simply delaying the reselection process until the MP returned from maternity leave would not solve the problem.
“It will be horrible for her to worry during her pregnancy, and then when she has a new baby, about what faces her immediately on her return to work,” she said.
Ms Harman added this situation could force an MP to go back to work earlier than they otherwise would.
She said that if members did want to get rid of their MP “they will only have to wait until the next general election”.
“That is not half as bad as the party becoming tarnished with the stain of maternity discrimination,” she said.
On Sunday, chair of the Parliamentary Labour Party John Cryer told the BBC there was “a lot of worry” about trigger ballots and possible deselections.
His wife, Ms Reeves – the MP for Lewisham West and Penge – had faced calls for a motion of no confidence by one member of her local party, but it was never moved.
Other MPs who faced such a vote – including Joan Ryan and Chris Leslie – chose to leave Labour to found the new party Change UK.
A handful of long-serving MPs – including Brexiteer Kate Hoey – have announced they will not be standing at the next general election.
While the next election is not scheduled to take place until May 2022, many believe there could be a snap poll in the autumn if there is deadlock between the next prime minister and Parliament over a no-deal Brexit.
Pregnant Labour MPs or those on maternity leave should be automatically reselected as a candidate in the next election, says a former deputy leader. Harriet Harman warned of a “justified outcry” if an MP going through the selection process miscarried.