Many women choose to take a general pregnancy vitamin supplement, and one of the popular ones is Elevit with Iodine. This contains Folic Acid, Iron, Vitamin D and Iodine, which are the mains ones that have some evidence to indicate possible benefit (although see Vitamin D comments in 'investigations' above). If you are not keen on taking a multivitamin the following should be considered:
Iodine: Low levels of iodine in our diets can result in poor thyroid development in the fetus which affects brain function. There is good evidence that iodine supplementation prevents this. Iodised salt or bread made with iodised salt is one of the main supplements in our community which reduces the risk of severe deficiency, but requirements increase in pregnancy and many Australians have low levels. The National Health and Medical Research Council of Australia (NHMRC) recommends that pregnant women take 150mcg of iodine daily.
More information on Iodine: NHMRC Guidelines
Folic Acid: Low levels of Folate or Folic Acid are associated with neural tube defects such as spina bifida. This can be reduced by taking 400mcg of Folate daily from 4 weeks prior to pregnancy and for the first 12 weeks. Higher risk women on anticonvulsants or with a previous affected pregnancy should take 5mg, a higher dose.
Iron: Routine iron supplementation is not essential but may help to reduce iron deficiency and low haemoglobin levels later in pregnancy. There is some evidence that treating low ferritin levels also helps prevent anaemia later in pregnancy (see investigations). On average you will need 30mg of elemental iron per day to maintain normal levels. Iron is found in meat, green vegetables, pulses and supplemented cereals. All pregnancy multivitamins contain iron but have amounts that vary from 5mg to 90mg. Iron supplements can be equally effective if taken 3-4 times per week rather than daily.
If you have become anaemic due to iron deficiency, I would recommend a much higher dose of 100-200mg iron per day. Products such as Fefol and Ferrograd Forte contain these higher doses, but can be constipating.
Herbal and liquid irons can be used as a preventative supplement but many are unlikely to meet requirements to treat anaemia unless taken in large amounts. Ferro Liquid is one exception and requires a prescription. Check the amount of elemental iron on the pack.
Vitamin D: (also see Investigations)
According to the UK based National Institute for Clinical Excellence (NICE), a routine Vitamin D supplement of 1000iu or 25mcg should be considered for women with risk factors including:
women of South Asian, African, Caribbean or Middle Eastern family origin
women who have limited exposure to sunlight, such as women who are predominantly housebound, or usually remain covered when outdoors
women who eat a diet particularly low in vitamin D, such as women who consume no oily fish, eggs, meat, vitamin D-fortified margarine or breakfast cereal
women with a pre-pregnancy body mass index above 30 kg/m
Many units now routinely check Vitamin D levels in pregnancy, but at this stage there is no evidence to suggest this approach is beneficial. Personally I feel that if you taking a general pregnancy multivitamin it is not essential that you take additional Vitamin D. Elevit contains 12.5mcg of vitamin D equal to 500units.
Calcium is important for bone, teeth, and milk development. For most women, the consumption of dairy products in pregnancy is enough to maintain calcium levels, however if you have a dairy free diet you should consider a calcium supplement (1000mg per day). There is some evidence that women at risk of blood pressure problems may benefit from calcium supplements.
More Information on supplements and diet: guidance.nice.org.uk/CG62