There are four major stages in an adult relationship - commitment, parenthood, the plateau and empty nesting. Sue Quilliam prepares you for each level.

Imagine life's a big department store and you're going up in the lift. At level after level you get out, stay for a while, then get back in the lift and move on up to exciting new 'shopping' opportunities, but you leave the lower levels behind.

So which 'level' are you on in your life at the moment? Here are four key stages which happen in most adult lives.

Level 1: Commitment - you find a serious relationship
Level 2: Parenthood - you have children
Level 3: Plateauing out - you reach your career peak
Level 4: Empty nesting - you let your children go

Leaving one life 'level' for another often means you're moving on to wonderful things, like partnership, or having a baby. But it also often means leaving things behind - leaving behind the freedom to please yourself when you take a partner, leaving behind regular sleep when you give birth.

So although many life levels are stages we look forward to, they have their downsides. You may feel sad about moving on and leaving the familiar behind. You may feel worried about rising to new challenges and new responsibilities.

So what can you do? Basically, make sure that at the point where you actually move from one level to the other you get particular support. Because that's when you're likely to be most stressed, even if it's a happy sort of stress. So look after yourself - physically, by taking more rest and getting other people to help; emotionally, by talking though any concerns with friends or your partner.

But also, every level has its own challenges, which need a particular response.

Level 1: Commitment
It's exciting to move in, get engaged or married. But you'll lose the independence of being single, and you'll have to cope with the give and take of partnership.

Adapt to this level by checking out your expectations beforehand - they'll be different to your partner's: everything from where you'll live to who washes the dishes, to how often you entertain his friends. Take the time to check out fully with each other what you each want and need and update that from time to time.

Level 2: Having children
Becoming a parent is wonderful. But it's also a big stress physically and a huge responsibility emotionally. You may go off sex because you're weary, he may feel sidelined because of the new arrival.

Adapt to this level by getting lots of support - from your health visitor, friends and family. If you're feeling particularly lonely and isolated, contact the organisation Meet-A-Mum; help line 020 8768 0123 (7pm-10pm Mon-Fri).

If you're really low, then it could be postnatal depression, so see your GP, and buy Antenatal and Post-natal Depression by Siobhan Curham; published by Vermilion £9.99. Or contact The Association for Post-natal Illness for advice and support. http://www.apni.org/

Also remember that you and your partner need regular time alone to rebuild your relationship now there is a new family member.

Level 3: Plateauing out
At some point, sooner or later, you're going to realise that as far as your working life is concerned, this is as good as it's going to get. Perhaps you get passed over for promotion. Perhaps someone younger than you gets the job you've always wanted. You may lose confidence and motivation - though you may also find it wonderful to simply stop trying and start living more for the moment.

Adapt to this level by... turning this one on its head and making it positive. Use the energy left over now you're easing back on your job to take a course, a new job, get a makeover or travel. If your self-confidence plummets read Overcoming Low Self-esteem by Melanie Fennell; published by Robinson £7.99.

Level 4: Empty nesting
Excellent - the children are off your hands and you can be a couple again. Just one problem. You miss the children, miss being needed, so you now feel a bit of a spare part. And it could be that you and your partner are so used to being parents that you've forgotten how to be close and loving partners.

Adapt to this level by making new friends to fill the spaces where your children used to be. Make plans to travel somewhere new. If you feel your relationship has lost its edge, don't be embarrassed to ask for help - contact your local Relate branch http://www.relate.org.uk/ (number in the phone book) for a list of relationship counsellors in your area.

Some of these Life Levels will be in the future for you. But it's still worthwhile looking ahead. If you know they're coming, and can plan and prepare, then you can be sure - at each level - to rise to the challenge.

For more in-depth reading on Life Levels and how they affect relationships, buy Crunch Points for Couples by Julia Cole; published by Sheldon Press £6.99.

All the best
Sue Quilliam