Labour MP Tulip Siddiq has postponed giving birth in order to vote on Britain's divorce deal with the EU on Tuesday (15).
Siddiq, 36, was due to have a Caesarian section on the big day, but medics have agreed to delay the operation until Thursday so that she can vote on the withdrawal agreement struck between London and Brussels.
She plans to be pushed through the voting lobby in parliament in a wheelchair.
"If my son enters the world even one day later than the doctors advised, but it's a world with a better chance of a strong relationship between Britain and Europe, then that's worth fighting for," she told the Evening Standard newspaper.
A source in prime minister Theresa May's Conservative party said it had offered to "pair" Siddiq, meaning a rival MP agreed not to vote to ensure her absence did not affect the outcome.
But Siddiq said she did not trust this informal system after the Conservatives broke a pair for a new mother MP last year.
Labour colleagues asked John Bercow, the speaker of the lower House of Commons, if Siddiq could have a proxy vote, but he said this was not in his power as such a voting system has not been implemented.
Bercow said he would like the procedure known as "nodding through" -- where an MP who is on the parliamentary estate but physically unable to cast their ballot has their vote counted -- extended to Siddiq's hospital bed in north London.
The new baby boy will be a great-grandson of the founding father of Bangladesh.
Siddiq is the grand-daughter of Sheikh Mujibur Rahman, the first president of Bangladesh.
Her aunt is Sheikh Hasina, who was sworn in as Bangladesh's prime minister for a record fourth term last week after a crushing election victory marred by deadly violence and claims of widespread rigging.
Bob Blackman MP speaks during the event