Oxford is second among the top 10 cities where women and girls are struggling to afford sanitary protection.
Period poverty is at its worst in Brighton and Hove where 46 per cent of women and girls say there are times they are unable to afford basic sanitary protection.
Oxford comes second where 40 per cent admit there are some months when they struggle.
The study of 2,000 females, who menstruate, revealed the 10 cities in the UK which are hardest hit by this widespread issue.
Overall, a quarter of the female population admit their menstruation is a challenging time because they now find it more difficult to afford period products compared to 12 months ago.
Of these, 90 per cent say the rising cost in living is already taking its toll, while a fifth now provide for another family member in addition to themselves.
One in 10 women admitted they had found it harder getting work during the pandemic, and an unfortunate seven per cent lost their job.
The study was commissioned by global hygiene and health company Essity, which has supported charity, In Kind Direct for 20 years.
Essity has created an educational video with advice for those affected by period poverty.
A spokesman said: "This is a really tough time for many, and we recognise our responsibility to try and help where we can to address the hardships so many are facing. As a result, we have just extended our commitment to donate 100,000 period products per month until the end of 2023 at least.
"Sanitary protection is a basic human requirement, and through charities like In Kind Direct there are ways women and girls can access the products they need.
"We just need to raise awareness of where to go, and how to get these items without feeling any sense of embarrassment or shame."
To cope at their time of the month, those who can't always afford their own protection have sourced free pads or tampons from work (36 per cent), the local hospital (30 per cent) or a GP (29 per cent).
While three in 10 have chosen to duck out of dinner with friends or work, 27 per cent have missed a party, and a quarter of younger girls have skipped school.
And sadly, 55 per cent of those who struggle have even missed a meal so they could pay for the products they needed.
Understandably, these females feel embarrassed (66 per cent), ashamed (56 per cent) and insecure (44 per cent) about not being able to fulfil their own basic needs.
While others feel smelly (39 per cent), inadequate (36 per cent) and even uneducated (17 per cent).
Of the quarter of women who can't always afford to buy their own sanitary products, 64 per cent have resorted to asking a friend or relative for theirs.
While 63 per cent have asked for money instead, so they could go shopping themselves.
And of those comfortable answering the question, posed in the OnePoll study, 28 per cent confessed to having stolen in the past because they didn't have the option of paying.
Rosanne Gray, CEO at In Kind Direct, said: "We support thousands of UK charitable organisations with donated period products. Many of these organisations provide period products and period education workshops to women and girls in their local community.
"We hear stories of women making their own pads using cloth or loo roll and plastic bags taken from supermarkets, because they simply can't afford these items.
"We don't want women and girls to fall behind through not accessing the products they need each month, missing work and school. Period products power confidence and boost self-esteem, giving people the chance of a brighter future.
"The monthly donation of Bodyform products from Essity has never been more needed. We are so proud of our long-standing partnership as we look to support even more women and girls, enabling them to thrive."
TOP 10 CITIES STRUGGLING TO AFFORD SANITARY PROTECTION
Brighton and Hove - 46 per cent
Birmingham - 34 per cent
Cambridge 32 per cent
York - 32 per cent
Southampton - 29 per cent
Belfast - 29 per cent
London - 28 per cent
Manchester - 28 per cent
Plymouth - 26 per cent ENDS