To stand or not to stand? That is the question.

I am sitting on a packed underground train and have come to from my far-too-early-in-the–morning fug to find my eyes level with a belly. It is quite a big belly, swollen and round and clearly straining the fabric in which it is enveloped. It leaves me with a split-second and difficult decision. Namely - fat or pregnant?

If it is the latter then I am in no doubt as to what I should do. I should proffer my seat with good wishes and without further delay. But is the woman in question in fact with child?

A quick upward glance. There are jowls, which could signify that weight is the issue. But then, are double chins and gestation mutually exclusive? I believe they are not.

Upon her lapel I can see no "baby on board" badge (something I never left the house without during my own pregnancy, mainly out of terror that someone would think I'd been at the pies rather than that I was six months up the duff). But then, she might not actually have one.

In those early months it is nothing short of a minefield

And therein lies the dilemma.

If, like me, you have spent the best part of a week consoling a friend who has been offered a seat when their "unborn child" is actually two large lokshen puddings and a family-size vat of cholent, then you too will be wary of making any kind of assumption.

Indeed, some might say that it is better to allow a pregnant woman to stand than to publicly humiliate someone who is not actually expecting.

There does, of course, come a stage when the ambiguity is less, well, ambiguous. But in those early months it is nothing short of a minefield.

Other public transport predicaments are generally far more clear-cut. Elderly? Crutches? Babe in arms? Heavy bags? My seat, with pleasure. Although I am constantly amazed by how many people on public transport can happily turn a blind eye to those in need.

Why not stick your toddler on your knee, for heaven's sake, rather than allowing the child to jump up and down on a seat that someone else could clearly do with? Why not teach your teens that sometimes there are backsides more deserving of a place of repose than their own? Whatever happened to basic etiquette and common courtesy?

Even when you can justly lay claim to a seat it doesn't necessarily mean others will give it up with good grace. Not long ago I had booked seats on a train back from Manchester only to find them occupied by a youngish man, his suitcase, and his violin. He was most affronted when I showed him our tickets and then asked him to move. "But my instrument is valuable" he cried in protest. "Not as valuable as my sanity or indeed my child" I told him, sticking it (the violin rather than the toddler) in the luggage rack and bidding him good day.

"Quite right" nodded the woman across the aisle. "Outrageous. What with you expecting as well."

There will be no more cholent in this house for a very long time to come.