Tulip Siddiq, who backs a second referendum, told the Evening Standard she has postponed her caesarean section by two days because she fears underhand tactics by the government.
Under House of Commons tradition, an MP from one party who is unable to attend a parliamentary vote can ask for a “pair” from another party – an agreement that sees one of their MPs also miss the vote.
Last year, the government broke one of its pairs when an opposition MP – Lib Dem Jo Swinson – was on maternity leave.
Conservative Party chair Brandon Lewis was meant to abstain as well to cancel out her absence, but ended up voting with the government.
Mr Lewis said it was an “honest mistake”, while chief whip Julian Smith said sorry and claimed the Tory chair had been “asked to vote in error”.
The row prompted accusations from opposition parties of underhand tactics.
Ms Siddiq, MP for the northwest London constituency of Hampstead and Kilburn, told the Standard that her husband Chris will take her through the lobby in a wheelchair to vote.
“If the pairing system is not honoured, there’s nothing I can do, and it’s going to be a very close vote,” she said.
“I’ve had no pressure at all from the whips to come and vote but this is the biggest vote of my lifetime.
“I’ve sat down with my husband Chris and he said to me this is my choice but that he would support me.
“I am thinking about my child’s future when I made this decision – his future in the world.
“If it comes to an absolute emergency, I will of course prioritise the baby’s health.”
Ms Siddiq had originally been due to give birth to her second child by elective caesarean on 4 February, the Standard reported.
But this was brought forward to either Monday or Tuesday after she developed gestational diabetes.
Ms Siddiq asked to move the date to Thursday, which doctors have agreed to.
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