Tokyo railways are providing pregnant women with badges in the hope of prompting other passengers to offer them seats.

The pink and blue badges reading "There is a baby in my belly" are being handed out at stations in the Kanto region to try to make train journeys easier for pregnant women, who are often left standing. No proof of pregnancy is required.

"Especially in the early stages, it is difficult to tell from someone's appearance whether they are pregnant," said an official at the health ministry, which came up with the idea. "But these early stages are rather unstable and it is important to take care."

The move comes as Japan scrambles for ways to persuade women to have more babies.