Former England captain David Beckham handed control of his Instagram account to a Ukrainian doctor in the city of Kharkiv on Sunday.
Dr Iryna, head of a regional perinatal centre, spent the day posting videos about the work medical professionals are doing in the midst of the conflict.
Footage showed newborns being treated and a basement to which patients have had to be moved to escape shelling.
Beckham, 46, has more than 71 million followers on Instagram.
The former Manchester United and Real Madrid star said he wanted to highlight the “amazing work Iryna and health workers like her are doing to save lives in Ukraine”.
Dr Iryna, who as well as running the centre serves as a paediatric anaesthesiologist, said her work had been “24/7” since the Russian invasion.
“The first days were the most difficult. We had to learn how to work with bombings and strikes,” she said.
“We are probably risking our lives but we don’t think about it at all. We love our work. Doctors and nurses here, we worry, we cry but none of us will give up.”
Kharkiv is Ukraine’s second biggest city and has been the target of Russian shelling for more than three weeks.
Dr Iryna described how, on the first day of the war, all pregnant women and mothers had to be moved into the basement of the centre.
“It was a terrible three hours that we spent together,” she said.
She added that babies receiving intensive care had to remain upstairs because the life-saving equipment on which they depended could not be moved.
Beckham also encouraged his followers to donate to Unicef, a UN aid agency for which he serves as an ambassador.
He and wife Victoria, who was a singer with the Spice Girls, are reported to have donated £1million to help fund the organisation’s work in Ukraine.