Heavily pregnant Sonari toils under the burning sun in fields dotted with bright yellow melons in Jacobabad, which last month became the hottest city on Earth.

Her 17-year-old neighbour Waderi, who gave birth a few weeks ago, is back working in temperatures that can exceed 50 degrees Celsius (122 degrees Fahrenheit), with her newborn lying on a blanket in the shade nearby so she can feed him when he cries.

¡°When the heat is coming and we¡¯re pregnant, we feel stressed,¡± said Sonari, who is in her mid-20s.