At the end of last night's Pramface Babies (Channel 4) I scanned the list of names in the production credits: Annabel, Josh, Clancie, Gemma and Charlotte all did their bit, headed up by producer and director Philippa. I made a wild guess that they were rather middle-class.

That's why they knew it would be jolly good fun to make a show that laughed at poor people with names such as Linzi, Kerrie and Krista. Not all poor people - that's just not cricket, and certainly would not get Philippa invited back to dinner parties. But we middle classes - so good at finding loopholes in tax law and grammar school admissions - have found another loophole here. You see, it's OK to laugh at poor people as long as they are lippy, under-educated teenagers (“pramface”, by the way, is a term of abuse for young mums on council estates).

So Pramface Babies may have been billed as a documentary - part of Channel 4's prestigious Cutting Edge series no less - but really it was a comedy with bits of a wildlife show thrown in. Comedy, because Philippa seemed to have the model of Little Britain's Vicky Pollard in mind when she visited the Liverpool Women's Hospital, selecting four teenage girls to follow in the first few weeks of becoming mothers.

It still could have been a good premise for a documentary, if it had found out much about these girls as mothers. Instead, it focused mainly on filming them in labour. Why? Because it was funny, of course! This is where the wildlife show bit came in - intrepid Philippa had ventured into the wilds of working-class Liverpool, persuaded some vulnerable teenagers barely more than children themselves that she was making an informative programme, and then mocked them for the silly things they said and did while enduring many hours of excruciating childbirth. Vicky Pollard may have exchanged her baby for a Westlife CD, but even the makers of Little Britain shied away from degrading their fictional character like this. Maybe they thought it was in bad taste.

More fool them! This stuff was comedy gold. The audience could chuckle at 18-year-old Laura, spending hours of her labour crying into her mobile phone as she failed to find the Awol father of her child. Later, when he finally called back, his first concern for his newborn was whether he had a “big chopper”.

Linzi's mother was too busy with her “ciggies” to care much for the daughter whom she called a “silly cow”. While the 19-year-old writhed in agony, she snapped “do as you're told” and “do you want me to lose my temper?” For any viewers who failed to get the joke, some of the girl's more ridiculous sayings were typed up on screen to frame the segments of the programme. Were we also meant to laugh when Krista mistakenly called her baby daughter “hopeless” rather than “helpless”?

Of course, Philippa would defend herself by saying that her subjects seemed - in the few minutes this was examined - to be good mothers. That four women she had randomly chosen out of the 8,000 who give birth in that hospital every year were not doing too badly did not add any substance. Without wider context, this told us precisely zilch about teenage motherhood. Lazy, unfocused, spoilt: this show was the true “pramface”.

Rather than fan the flames of the heated Ashes to Ashes (BBC One) debate, I will simply list, in as neutral a manner as I can, the notable developments from last night's episode. 1. Keeley Hawes (playing the police heroine Alex Drake) finally hoisted her blouse off her bare shoulder - but for fans of her bra straps, don't worry, they are back next week. 2. Speaking of which, never has the sound effect of a chafing white faux-leather jacket been used so eloquently. Drake's wardrobe deserves its own speaking part. 3. After 28 years, the show has managed the seemingly impossible: it has made Ultravox's Vienna seem meaningful. When Drake lay dying from cold, I found the cheesy voice of Midge Ure (“Walked in the cold air, Freezing breath on a windowpane”) almost moving. That, I never expected. 4. After weeks of racking my brain about who Hawes has based her character on, I had the eureka moment: Kate Bush! She has Bush's hair, Bush's nuttiness, and, last night, a lot of very Bush-ian sequences of rolling through brightly coloured sheets.

Out of the box

Wednesday night saw Channel 4's primetime shamefully stuffed with repeats. Of course it doesn't call them that, because property shows are never “repeated”, they're “revisited”. So in Relocation Relocation, Kirsty and Phil “revisited” a show they made years ago by tacking approximately six minutes of new footage on to an hour-long rehash. This was followed by Kevin McCloud, in Grand Designs Revisited, momentarily popping his head round the door of a house that he'd featured in depth a few series ago. What Channel 4 has failed to grasp is that typical viewers of these property shows are both loyal and obsessive. They remember the original show in every detail. To make a new series and pack half of it with repeats insults their devotion - if you want a follow-up show, at least feature half a dozen cases at the same time.

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