Detectives also say the fatal stabbing of Tory MP Sir David Amess has a potential link to Islamist extremism.
Boris Johnson has led tributes from the political world for Sir David Amess.
Kim Leadbeater was elected as MP for her murdered sister's constituency in a by-election in July.
A lab in Wolverhampton is suspended as 43,000 people in England and Wales are potentially affected.
Paige Thomas lost her baby to pre-eclampsia and wants tests rolled out for all women.