The only supplements that are recommended for every pregnant woman are folic acid and vitamin D.
Ideally, 400 micrograms of folic acid should be taken before you become pregnant up until you’re about 12 weeks pregnant. This is to support your baby’s development and prevent neural tube defects, as folic acid helps form the connection between the spinal tissue in and around your spinal cord. You would only need to take more than the recommended amount if you or your partner has a history of neural tube defects, if you have diabetes, if you’re taking anti-epilepsy drugs, if you’re taking antiviral drugs for HIV or if your BMI is over 30. If you’re unsure, speak to your doctor.
All pregnant women should also take 10 micrograms of vitamin D a day, which is exactly the same recommendation as the rest of the adult population. This is to help with your child’s development (particularly bone development) and make sure they have enough vitamin D to get them through the first few months of life.
Other than that, you might find it helpful to take a multivitamin, an iron supplement, B12 and Omega 3, depending on your diet. Do not take cod liver oil or vitamin A (retinol) when you’re pregnant, as these could harm the baby. Also check the skincare products you use, as some of these now contain retinoids.