Pregnancies in women over 35 are often referred to as “high risk”, but this does not take into account a woman’s individual circumstances. How great is the chance of developing problems in reality?

1. How tired am I likely to get?
Persistent tiredness is likely to be the most significant physical change in the early days of the pregnancy. Younger women suffer from it, too, but older women who have had babies in their early 20s and again in their late 30s report that it is greater when older. Give into it if you can, but if, as the likelihood is, you can’t swop a 10am meeting for 40 winks, feel free to skip social events afterwork and go to bed early. You may also be suffering from morning sickness: 75per cent of pregnant women do, although it generally starts to subside after the first trimester.

2. What tests to detect abnormalities should I have?
You will be offered a range of tests but some are more important for older women than for younger ones.

According to Dr Laura Goetzl, the author of the newly published book, Conception and pregnancy over 35: “As women age, there is an increased risk of having a baby with problems caused by extra or missing chromosomes, particularly Down’s syndrome.” The decision to be tested and which tests to have is a question of individual choice.

What you are offered will vary according to where you are, but non-invasive screening tests telling you your risk of having a Down’s syndrome baby are standard. A test known as the maternal serum screening test is almost universally available. It is administered during the second trimester, at 15 weeks, is non- invasive and tests a sample of blood for three chemicals. The risk of Down’s or other chromosomal abnormalities, and spina bifida, is calculated by using these results combined with age.

A report on pregnancy screening and scanning below 24 weeks, published by the Scottish Health Technology Assessment Centre (which assesses the effectiveness of new healthcare innovations) , has recommended that an earlier screening test at 12 weeks - the combined ultrasound and biochemical screening test (Cubs) - should be available all over Scotland by 2007. It is currently not widely available, although it is offered at the Queen Mother’s Hospital in Glasgow.

According to Dr Alan Cameron, a consultant obstetrician at the hospital and president of the British Maternal and Foetal Medicine Society, it is a better test than the 15-week test as it is 90per cent accurate at detecting Down’s syndrome compared to 65per cent.

To get a 100per cent definitive result, you could have an amniocentesis at around 15-18 weeks (when amniotic f luid, which contains cells from the baby, is drawn out using a needle for chromosomal analysis) or chorionic villus sampling (CVS) at around 10 weeks (when a small fragment of the placenta is removed).

3. How many ultrasounds do women have and when?
Women in Scotland have one or two, depending on where you are and what facilities are available.

The first is the nuchal scan at 12 weeks which checks that the baby’s weight matches your due date and assesses the foetus’s development.

The Scottish Health Technology Assessment centre report recommends a second scan at 20 weeks, a foetal anatomy scan which can detect how the baby’s brain and organs are developing and 95per cent of neural tube defects as well as cleft lip and club foot.

4. Are there any risks attached to these tests?
The non-invasive screening tests do not carry any risk but amniocentesis carries a 1per cent risk of miscarriage, while CVS carries a 2per cent risk. Many hospitals discuss the amniocentesis and CVS options with women after 37, because above that age, the risk of Down’s comes down to one in 350.

5. My pregnancy is unplanned and I have mixed feelings about it as I had not planned to make career changes at this stage. Could this be a bad move for me?
It can be difficult to come to terms with feelings of anger, hopelessness or depression at an unplanned pregnancy, especially if you have friends who are trying for children. DrGoetzl says: “Give yourself permission to grieve for the things you have to give up, but remember that you still have many choices.” Every woman is an individual and has to find how to balance her work and social life with the demands of motherhood.

Do not imagine that there is a wrong and a right way to do it.

6. I have a stressful job - could that put stress on the pregnancy?
Dr Cameron says: “There is some evidence to suggest that stressful jobs have an impact, but it’s difficult to show cause and effect.”

It appears to be the case that women with a great deal of stress in their jobs are at higher risk of miscarriage, having small babies and developing high blood pressure.

7. Is vigorous exercise to be avoided during pregnancy?
Aerobic exercise should be avoided, especially late in pregnancy.

Swimming is the best option.

8. Are women over 35 more prone to gain baby weight and will they be stuck with it?
Good news: there is no evidence to suggest that because you are older you will gain more weight during pregnancy or have more trouble shifting it afterwards.

9. I have heard that there is a higher likelihood of gestational diabetes, pre-eclampsia (high blood pressure) and multiple gestations among older mothers. Is this true?

Dr Cameron agrees that all three are more common in older mothers- to-be. He says: “All pregnancy complications are more prevalent in older women. They are also more prevalent in teenagers. The extremes of reproductive life are more at risk.”

This is true of maternal mortality, too, although it is very, very rare at any age. Mothers over 40 are more likely to die, partly as they are more likely to have health problems such as Diabetes or Coronary heart disease at the outset.

10. Am I at higher risk of going into pre-term labour or having labour complications?
“Pre-term labour would not go up with age, ” says Dr Cameron.

As for complications during labour, Dr Goetzl advises that while there is some evidence that in first-time oldermothers “the first stage of active labour can take longer than that of a younger first- time mother”, the principles basically remain the same irrespective of age.

Conception and Labour over 35 by Dr Laura Goetzl, Dorling Kindersley, [pounds]12.99.