Myleene Klass has revealed she has suffered four miscarriages and said she hopes sharing her experiences will help "even one lost soul".
The monarch was joined by her grandson the Duke of Cambridge at the Defence Science and Technology Laboratory near Salisbury.
Moving to Tier 2 will see the nine million people living in the capital banned from mixing with other households indoors, including in pubs and restaurants.
Due to a spike in cases of the virus, Liverpool was placed in tier three - the most serious “very high” risk category.
Experts called for more research as they warned that even people with mild illness can suffer long-term after-effects.
Zoe Powell and three of her children died on the A40 near Oxford on Monday night.
Professor Graham Medley, from Sage, said there was ‘mixed evidence’ that the current three-tier system would work.
Nearly 5,000 people have tested positive for Covid-19 in a week in the Anglia region and cases are doubling in 13 districts.
Labour’s leader has pushed for a short national lockdown.
A late night meeting of the Executive takes place at Stormont, as ministers discuss measures to curb the spread of coronavirus.