Her mother, Jo Hansford, is one of the most experienced and internationally respected names in hairdressing, credited with maintaining the glossy manes of celebrities such as Liz Hurley, Angelina Jolie and Yasmin Le Bon. So you would expect hair to be the last of Joanna Hansford’s worries; and it was, until she discovered just what an effect becoming a mother can have on hair, when her first baby, Elsie (a redhead), was born in July.

“My hair tends to be greasy and lank, and I still try to wash and blow-dry it every day,” she says, “but half an hour later it’s up in a ponytail. Elsie is starting to grab handfuls of my hair when I change her nappy.”

As managing director of the family firm, Joanna, 31, was used to running not only a high-profile business, but her own life. “I thought the baby would fit into it,” she says, laughing. “It’s hard when you are older to break a well-established routine.”

Despite first-trimester longings for cheese and pickle, an untypical aversion to green vegetables — Joanna is vegetarian — and a huge carbohydrate craving, she managed to maintain a healthy lifestyle, getting extra protein with “meaty” fish such as tuna, and swimming regularly. It seemed to pay off. “For the first three months my hair did seem to get thicker, which was nice because I’m not used to having much!” If locks look more lush and glossy during pregnancy, it’s not because more of it is growing but because the normal cycle of hair loss stops. The flip side is that after delivery all the hair that should have been shed during the previous nine months can come out, sometimes all at once. The precise cause is not clear, but one theory is a link between a huge increase in the hormone progesterone produced during pregnancy, which falls post-partum.

What about the controversial question of chemicals in hair dye damaging the foetus? Granny Jo, who started the Jo Hansford hair salon in 1993, says reassuringly that the products are less harsh than they used to be and are tested more rigorously, although she sounds a note of caution about the dye paraphenylene diamene (PPD), which in rare cases can cause an allergic reaction.

But the Hansfords understand that some women just don’t fancy the idea of chemical dyes while expecting, and they suggest highlights instead, which colour only the hair shaft and don’t enter the bloodstream via the scalp. They also last longer than a tint — up to 12 weeks — saving time and money.

While there isn’t a great deal of scientific evidence on the link between diet and hair quality, some nutritionists argue that a deficiency in omega-3s and fatty acid can make hair dull and dry. Full marks to Joannna for eating lots of omega-3-rich tuna, then. Diet, however, is something that both the Hansfords believe contributes far more to a healthy hair than a load of fancy products.

Joanna took over-the-counter pregnancy supplements, but since Elsie’s birth she has been getting all her nutrients from her diet. Jo, on the other hand, is particularly enthusiastic about the benefits of vitamin B12. The World Health Organisation recommends a 40 per cent increase in intake of the nutrient for pregnant mothers, and while a healthy diet will take care of any deficiency for most of us, Jo took it in the form of intra-muscular injections while expecting Joanna and her brother, Daniel. “I saw a few of my clients losing their hairline about six months after giving birth and thought that’s not going to happen to me. A bald hairdresser? That’s terrible!”

Jo Hansford, 19 Mount Street, London W1 (020-7495 7774)

Hints with a tint

If you don’t have much time to linger in the bathroom, leave the conditioner in your hair, and tie up with a clip if it’s long, or stick it under a shower cap until you have time to rinse it off. The cap will create heat, which helps to open the follicles and allows the conditioner to penetrate more deeply.

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