"I think parodies are great," says mum-of-one and HuffPost UK editor Melanie Hick.
"I'd wear a badge that said 'no preggers, just pies,' but it's just polite to offer a seat and because people aren't polite enough, we have to wear flipping badges."
Adam Armitage from Wayward Studio told HuffPost UK:
"This badge series is totally tongue in cheek and meant to be taken as a comment on our need to express our wishes without vocalising them. I believe that's called British stiff upper lip!
"If anyone is wearing this badge in a legitimate attempt to steal a seat from a pregnant women then I would be very surprised. They obviously do not understand this humour.
"There is nothing stopping pregnant ladies from wearing these parodies as well though. Who knows, perhaps it may even get people talking again!"
A second badge in the range reads: "I'm hungover!"
"I think the badges are just a bit funny and tongue in cheek," she says.
"I can't imagine anyone truly thinks something like having a hangover trumps being heavily pregnant.
"I've been hungover (many times). I've been pregnant (twice). And I tell you what? Give me a hangover anytime.
"I can imagine being on a cramped underground whilst feeling sick, or having leg cramps or a tiny human wriggling in your belly as pretty rubbish and hard work.
"Wear the badges but expect angry glares and a weepy/grumpy lady if you don't get up and offer your seat!"
"I'm pretty sure pregnant women would probably love to not have to wear the original baby on board badge at all," adds Hick who blogs at Mumspo.com.
"I was reluctant to wear one when I was pregnant.
"But when you've got 10 pounds of human bearing down on your bladder, smashing your lower back and core muscles to smithereens while peeling your pelvis in half and most people can't be arsed to give you a seat in case they miss out on stroking their iPhone for a minute, then we'll have to keep on wearing the Baby on Board badge.
"For me, the baby on board badge meant not having to talk to people and ask for a seat on every. single. transport interchange.
"Be honest. No-one wants to talk to people on London transport and when you're pregnant you're forced to engage with people every time you change a bus, train or tube. That's damned annoying."
Tommy's midwife Anna Nella agrees that the importance of the original baby on board badges is often overlooked:
"I think some people have taken to be a little confronted by the baby on board badges," she says.
"They think women are whining and making a fuss, but actually it takes a lot of energy to grow a baby and in that first trimester there's so much going on.
"Actually in early pregnancy you feel probably the worst that you’ll feel throughout the pregnancy.
"All the hormonal, metabolic and structural changes that are going on are completely out of proportion to the size of the baby, who at six weeks is the size of a lentil. At that stage women obviously don’t show that they’re pregnant, but they can feel awful.
"They could be feeling very nauseous, suffering from bleeding, dizziness and/or insomnia and they may be more sensitive to smells on the tube which can make you feel more unwell.
"So if you've got this combination of things and you've got a long commute standing squashed under somebody's armpit, it is likely to compound any symptoms you have.
"Fainting doesn't damage the baby, but it could end up with the poor woman hitting herself on the way down, so there's hundreds of reasons to give a woman a seat in the first trimester."
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