Women who are chronically and severely anaemic (many in developing countries, for example, where haemoglobin levels of 5-6g/dl are, tragically, commonplace) may give birth to smaller babies. Generally, however, it is the mother who suffers as her reserves are diverted to her unborn baby. Severe anaemia is associated with fatigue and depression, increases the risk of infection, and reduces the mother’s ability to deal with bleeding after childbirth. In this country, a woman who is severely anaemic will probably be encouraged to have her baby in hospital, to enable prompt and effective treatment should she bleed heavily following the birth. She may have an intravenous infusion running slowly throughout labour – just in case – and will be encouraged to accept ‘active management’ of the third stage of labour. (‘Active management’ of the third stage means that a drug is given to speed up separation of the placenta, which is then gently pulled out from the cervix/vagina.)There is considerable disagreement amongst experts concerning what constitutes ‘anaemia’ in pregnancy, and the need (or otherwise) for iron tablets. This is because it is normal (even desirable) for the level of haemoglobin in your blood to fall during pregnancy. For most women this means a drop from an average of 13g/dl pre-pregnancy to 10-11 g/dl. (Haemoglobin is the iron component of red blood cells. Haemoglobin levels are routinely measured at intervals during pregnancy.) The normal fall in the haemoglobin is a reflection of the increase in the volume of blood plasma (the liquid part of blood) carried during pregnancy. Although the number of red blood cells also rise, the increase in plasma is proportionately much greater – hence the apparent ‘anaemia’. Experts argue over at what point this normal ‘haemodilution’ (dilution of the haemoglobin) becomes true anaemia. This is not just an academic argument – there are several problems associated with taking iron tablets, so it is important to be sure that they are really needed. Nowadays, most midwives and doctors recommend iron tablets if the haemoglobin level falls below 10.5g/dl. Others accept levels as low as 9g/dl as normal in pregnancy, especially if the woman is feeling fit and well. Your midwife will be able to tell you at what level iron tablets are recommended in your area. If there is doubt, there are further blood tests that can be done to see whether iron tablets are really needed, the most usual being assessment of the ‘mean corpuscular volume’ (MCV).
Whether or not iron tablets are taken during pregnancy, diet remains of vital importance. Include an iron-rich food in each meal, and remember whilst vitamin C increases the absorption of iron from food, tea may reduce it. Iron tablets are best taken 30 minutes or so before a meal.