`Any other life event that leaves 40 per cent of women in some sort of depression would have huge resources channelled into it." So says babycare guru Penelope Leach, speaking to E&L about childbirth and the early weeks of parenthood. "It should be a joyous time."

Today's new mum is likely to have been educated through secondary school, may have had the chance of third-level qualifications, have her own house, car, salary and hold a position of responsibility unimaginable for a woman in previous decades; yet when it comes to dealing with a new baby she may not have a fraction of the confidence or experience of her own mum or granny with their first born.

Many women now live some distance from their original families. They may have little contact with children and may be unfamiliar with babies except for those plump gurgling ones in the ads. However even those who work as teachers looking after 30-plus kids each day can be thrown by the shock of a new baby and the upheaval it entails. Being suddenly responsible for a tiny baby when you're exhausted, and possibly aching in various places, can be quite a daunting experience. "So many young women have never even seen a new baby before. It is impossible to conceive what it is going to be like. A new baby's wobbly head may be very surprising. "And while they know that breast is best for baby, they may not be sure exactly how breast and baby go together."

Many couples see birth as the end of the journey rather than the beginning of a new one. "It's difficult not to see birth as the climax of pregnancy. And it can then be a surprise when you have a baby at the end. It's important to think beyond this astonishingly important life event. "Certain things are very hard to imagine beforehand, such as the whole emotional side - You can't imagine how you'll feel. And it can be shattering for an efficient organiser in a very high-powered job, where she ensures that everything runs smoothly, to be faced with the realty of a little wobbly baby. "But it's not only shock - it's excitement and anticlimax too. We need to let these new mothers know that it is okay to be in your pyjamas in the middle of the afternoon when you have a six-day-old baby; that it's normal in the early days to spend three hours sitting and gazing at your tiny baby and another three hours crying." (That's the new mum crying, not the baby.)

Leach stresses the need to be realistic about the changes that baby will bring. Some parents have unrealistic ideas about parenthood; they plan, for example, for mother to take the baby to the office with her when she returns to work, which may work for a couple of months - depending on the baby - but isn't practical in the long term. They plan holidays, such as treks through the Himalayas, that they have enjoyed before but which could be hell with a young baby.

Some women, particularly those who have been very independent, very much in control of their own lives, find it very difficult to adjust to this tiny scrap who doesn't stick to any routine and who demands huge amounts of time and attention. The state of the previously pristine house - now filled with ever-growing piles of washing and baby paraphernalia amidst the congratulatory flowers and cards - doesn't help.

Helen, a mother of two small children, is a classic example of someone who was overwhelmed by the changes brought about by the birth of her first baby - she was in a state of confusion and depression for weeks. "It was all such a shock. I really loved my baby but I was used to being in charge of my life, to things going to plan and I found it took 45 minutes just to get ready to go out with the baby in the car! "At first my whole day was taken up with looking after her, just feeding her and changing her and all that. I was exhausted and disappointed in myself that it took so much out of me and that I didn't seem to be getting anything else done. I was too tired to cook dinner and I hadn't managed to clean anything in the house. I hated Paul to see me so incompetent. "Then when I went back to work it was hectic. It was great to be in adult company again, but at times I was like a zombie after broken nights. And I missed her terribly during the day, which I hadn't anticipated. It took me a while to realise that life was so very different now and to adjust to that."

Some parents, Leach says, delay the inevitable. "It makes me sad to see a couple trying desperately to keep everything the same with the first baby, then with a second pregnancy finding it all too difficult and too stressful and taking a year off." Society, she says, is not very baby-friendly or even parent-friendly. She feels it should be much easier for working mothers - many of whom have invaluable experience to contribute to the workplace - to be able to negotiate a part-time position for those important early years. Her Baby and Child (Penguin) has been essential reading for thousands of people struggling with the highs and lows of new parenthood, providing the advice, support and comfort they need - much of which was traditionally supplied by the extended family. Over the last 20 years it has sold millions of copies and been reprinted several times. Recently Leach felt the need to update it. "The social context has changed so much. When I wrote the first edition the vast majority of women stayed at home with their children until they were at least three and often five years of age and dads played a very minor role. Now the majority of new mums are working parents and fathers' participation has changed immensely. "In the 1970s only children were the exception, yet now, in some areas, they are practically the norm. And the age at which women have their first baby has changed radically."

Leach's advice for prospective parents to minimise the shock of the new baby is to read the chapters in the baby books on "the early weeks" before the baby is born - and to accept offers of real help after the birth.

Penelope Leach will present a 40-minute seminar, What to Expect Beyond Your Delivery Date, as part of the Baby and Kids Show at the RDS, Dublin, this Saturday at 10 a.m.