A TRICKY THING sex. You spend your formative years taking elaborate precautions to prevent pregnancy and suffering agonies at the tiniest hint of a baby. Then when you and your partner are ready to embrace parenthood with open arms and can finally enjoy sex without a safety net, you suffer agonies all over again if a baby fails to materialise immediately. Even when pregnancy is achieved, the sex question still looms large: 'To do it or not to do it?' In late pregnancy, the more thoughtful: 'Is it physically possible to do it?' and once the little bundle of joy is delivered safely into your arms: 'We are never doing 'it' again.' Trying to get pregnant can be a frustrating time. Some women conceive merely by thinking about it, while others take infinitely longer. Even if a couple has been trying for a baby for only a couple of months, it is possible to become obsessed with having sex at exactly the right time. Reason flies out the window as you tearfully explain to your partner that he cannot possibly watch football on television ... you are hatching an egg. 'People have to be realistic about this,' says Dr Lucy Lord. 'The chances of a healthy couple conceiving each month are 15 to 25 per cent, depending on age. They really shouldn't panic if it doesn't happen instantly.' Clutching a pregnancy test stick that registers positive is a truly magical moment. But even as you both perform a victory dance around the bathroom, female hormones are disrupting your sex life. Morning sickness in early pregnancy is deeply unsexy and renders most women incapable of doing anything, least of all making love. Fatigue is also insidious, and the best-laid romantic plans often fall apart as the expectant mother falls asleep by candlelight. There is also the fear of harming the baby or causing miscarriage. 'A normal pregnancy is not harmed by having sex,' says Lord, 'but if there is bleeding or discomfort, of course a woman should consult her doctor.' All this can be deeply frustrating to partners who, having thoroughly enjoyed the whole baby-making process, finds it difficult to understand why sex is no longer a priority. As a couple, it is essential to express concerns or worries while assuring each other that normal service will resume as soon as possible. As pregnancy progresses, a woman will not only feel fabulous, but sexual desire can return with a vengeance. Her body is literally blooming. The irony is that, once the 'bump' is very much in evidence, then her partner might worry about whether making love is a good idea. There is the feeling that two is company but three is definitely a crowd. The baby is unaware of what is going on and merely responds to movement or even the sound of voices. In late pregnancy, sex is definitely a challenge. Tiredness returns and most women are struggling to remain upright rather than trying to be a goddess between the sheets. Some men say the sight of their heavily pregnant partner is a real sexual thrill; others are less than impressed. Talk to each other and talk to your doctor, and do what feels right for you. Most women feel an increased need for reassurance at this time, so anything romantic, such as massage, will bring you closer without the anxiety of active sex. 'When to resume your love life after giving birth is an extremely personal decision,' says Lord. 'It depends entirely on the birth experience itself, the woman's physical state afterwards and her own general sense of well-being. It can range from a week to months.' A woman's body undergoes radical change after birth. Hormones must return to pre-pregnancy levels; a milk supply has to be established and the body has to heal. All this happens while you are learning to be the perfect parents with a fiercely demanding new baby in the home. It is vital to appreciate the upheaval you are both going through and give yourselves time to adjust. Sheer fatigue is the most effective sexual turn-off, and the demands of coping with a new baby night and day can be exhausting. Sleep deprivation is long-term torture and this must be recognised by both parents. It is also important for women not to shut out their partners, say experts. Having a baby is an extremely absorbing process and a woman can become so wrapped up in her newborn she has little time for anything else. But a man's emotional needs are just as important now, if not more so, than before the baby's birth, and he is unlikely to enjoy the same intimate level of satisfaction from the baby as a woman does. Mother of four Nicky Loiterton says it is vital to resume your sex life as soon as possible. 'The worst time of all with a new baby is when it is five to 10 weeks old,' she says. 'The novelty has worn off and you are just so knackered and fed up with it all. If you can manage to have sex before it all gets too much, it kind of confirms that everything will be all right and you have reconnected with each other.' However, the bad news is that hormonal changes after the baby is born can make sex uncomfortable. 'It's almost like a mini-menopause, and what many people don't appreciate is that this is the case for both natural and caesarian births,' says Lord. Thankfully, she says, this is a temporary state, but giving birth affects women in different ways and many just don't feel ready to resume sex at an early stage. However, it is vital for a couple to maintain intimacy and communication. The key is to be as relaxed as possible and be prepared that sex may take some time to achieve. If sex feels uncomfortable, don't worry about it. Just go back to kissing and cuddling and try again on another occasion. There may well be several false starts before you both feel ready to go the whole way. The important thing is that you and your partner are together physically. Sex is a natural and intrinsic part of your relationship and there is no need for the process of pregnancy and birth to undermine it. As a couple you will need to talk to each other more, experiment a little bit more and, above all, laugh a lot more. By adapting your physical relationship to a changing body and moods, many couples discover an openness and intimacy that gives a new breadth to their sex life - a happy state of affairs that will continue long after the baby has been born.