Those Brits haven't been living up to their polite stereotype, according to a recent article in the Daily Mail, with commuters not offering up their seats to pregnant women.

The reason? Apparently, curves are confusing. It's unclear whether a woman is pregnant or just plain overweight, and rather than risk offending, people are staying put.

The article cites two surveys recently conducted in the U.K., which have found that men (and women, in fact) rarely offer their seats to expectant mothers, who are very likely to be suffering from some kind of ailment, whether it's a backache, swelling or just the irritation of carrying around an extra 30-plus pounds of weight in the sweltering heat.

One survey from parenting website Gurgle, which interviewed over 1,000 pregnant women in their final trimester, found that more than four in five pregnant women (84 percent) had been made to stand on public transportation. Meanwhile, baby charity Tommy's also came to the conclusion (using separate research) that a majority of mothers-to-be were rarely being offered seats.

What's going on here? Has gallantry plunged even further into the abyss, or are people genuinely confused and mortified to mistake a bigger belly for a baby?

Nifa McLaughlin, editor of Gurgle, told the Mail, "It is ridiculous that the health of young mums is being put at risk because of embarrassment. We've all been in that awkward situation, but we would encourage commuters to swallow their pride and offer their seats. It is worth risking a red face if it ensures that a pregnant woman is able to complete a crowded rush hour journey safely."

To ease the confusion, the website has launched a Baby on Board campaign, providing pins for pregnant women to wear and encouraging them to speak up for their right to sit down. Now, we'd be interested in the results of that survey ...