Carrie Johnson, the wife of Boris Johnson, has been hospitalised with severe dehydration just weeks after giving birth.
The incident prompted a stark warning from Ms Johnson about the critical importance of proper food and fluid intake for new mothers.
The 37-year-old welcomed Poppy Eliza Josephine Johnson – her fourth child with the former prime minister – on 21 May.
She revealed her two-night hospital stay on an Instagram story.
Sharing a photo of herself cradling her newborn in hospital, she remarked that the experience was "not on my postpartum bingo card".
Ms Johnson’s personal ordeal comes as Britain prepares for another heatwave this weekend, with temperatures expected to exceed 30C and an amber heat health alert already in place.
She wrote: “Being hospitalised for two nights for severe dehydration was not on my postpartum bingo card.”
She urged breastfeeding mothers to make sure they eat and drink enough, “especially if your babe is clusterfeeding”.
Advice on the NHS website tells new mothers to drink plenty of fluids and to have a drink beside them as the settle down to breastfeed.
Water, lower fat milks, lower sugar or sugar-free drinks are all good choices, according to the NHS.
Ms Johnson thanked everyone who has helped them get through a “brutal” week.
With an Amber Heat Health alert declared for the East Midlands, South East, South West, East of England and London, it's worth watching out for those who might find it difficult to cope with high temperatures. ☀️ 🌡️
— UK Health Security Agency (@UKHSA) June 27, 2025
Check our blog post for handy tips: https://t.co/mCZIFKwOZ5 pic.twitter.com/CSnx4ON86s
She wrote: “This week has honestly been brutal. “Mastitis (me), reflux (her), dehydration (me). What a pair we are!
“But thank you for all the kind messages, especially all the brilliant advice on reflux. Really appreciate it and made me feel way less alone going thru it all.
“And as ever, thanks to our amazing NHS.”
The amber heat health alert, which covers London, the East Midlands, South East, South West and East of England, came into force on Friday and will last until 6pm on Tuesday.
The UK Health Security Agency (UKHSA) has also issued a yellow alert for Yorkshire and Humber and the West Midlands for the same time period, with the agency warning of significant impacts across health and social care services.
The heatwave is also affecting broad parts of mainland Europe, and a Dutch tourist died of heatstroke in Mallorca, according to local reports.
The 34-year-old collapsed while hiking with friends in Camí de Son Sales, the Majorca Daily Bulletin reported.
Emergency services attempted to resuscitate him but were unable to, according to the publication.
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Temperatures could hit 30C on Saturday amid amber heat health alert