19 November 2025
The Ultimate Guide to Prenatal Vitamins: What You Really Need to Know
During pregnancy, your body works overtime to nourish both you and your growing baby. Even with a balanced diet, it can be difficult to get enough of certain key nutrients.
That is why it is essential to take prenatal vitamins to support the healthy development of your baby and to reduce the risk of birth defects. Prenatal vitamins will also help you feel your best throughout your pregnancy journey.
How to Choose the Right Prenatal Vitamin for You
With so many options lining pharmacy shelves and appearing online, choosing a prenatal vitamin can feel confusing. Marketing claims often make every product sound essential. In reality, what matters most is ensuring you are meeting a few key nutrient requirements based on evidence and your individual health needs.
Here is a clear, practical guide to help you understand what truly matters.
Folate
Folate is critical before conception and during early pregnancy. It helps reduce the risk of neural tube defects, including spina bifida, which develop in the first few weeks after conception. This often occurs before many women realise they are pregnant.
If you are planning to conceive, begin taking folate at least three months before trying for a baby.
Dr Peter’s tip
Some women require a higher dose of folate, particularly those with a family history of neural tube defects, certain medical conditions, or those taking specific medications. A preconception consultation and blood test can help determine your individual requirements.
Iron | 27 mg daily
During pregnancy, your blood volume increases significantly. Iron supports this expansion and helps prevent iron deficiency anaemia.
Low iron levels can contribute to fatigue, weakness and, in more severe cases, complications for both mother and baby.
Look for a prenatal vitamin that contains a well absorbed, gentle form of iron. Pairing iron with vitamin C rich foods can further improve absorption.
Be aware that iron may cause constipation. If this occurs, speak with your doctor about adjusting the formulation or dose.
Iodine | 150 micrograms daily
Iodine plays an essential role in your baby’s brain and thyroid development.
In Australia, mild iodine deficiency is not uncommon, which makes supplementation particularly important. Choose a prenatal vitamin that contains at least 150 micrograms of iodine, unless your obstetrician advises otherwise.
Vitamin D | 400 to 1000 IU daily
Vitamin D supports bone health, immune function and overall wellbeing.
Many women have low vitamin D levels, especially during winter months or if they spend limited time outdoors. A simple blood test can determine your levels. If you are deficient, a higher dose may be recommended under medical supervision.
Omega-3 Fatty Acids (DHA)
DHA is an omega-3 fatty acid that supports your baby’s brain, eye and nervous system development.
If you do not eat oily fish at least twice per week, consider a prenatal vitamin that includes DHA or discuss a separate omega-3 supplement with your doctor.
Other Important Nutrients
- Calcium
Supports the development of strong bones and teeth. - Vitamin B12
Particularly important for women who follow vegetarian or vegan diets. - Zinc
Contributes to healthy growth and immune function.
When to Start and How Long You Should Take Your Prenatal Vitamins
If you are planning a pregnancy, it is a good idea to start taking a prenatal vitamin a few months before trying to conceive. This is particularly important for nutrients like folate, which play a key role very early in pregnancy, often before you even realise you are pregnant.
Most women continue their prenatal vitamin throughout pregnancy. Some also keep taking certain supplements while breastfeeding, depending on their diet, recovery and individual needs.
Already pregnant and have not started yet? That is completely okay. Begin as soon as you can and have a chat with your obstetrician or GP at your next appointment to make sure you are taking the right supplement and dose for you.
Can You Take Too Many Prenatal Vitamins?
Yes, it is possible to have too much of a good thing. More is not always better when it comes to supplements, especially during pregnancy.
High doses of certain nutrients, such as vitamin A or selenium, can be harmful if taken in excess. This is why it is important not to double up on supplements or combine multiple products without medical guidance.
If you are unsure whether your prenatal vitamin is appropriate, or if you are considering adding extra supplements, speak with your health care provider to ensure the dose and combination are right for you.
Tips for Choosing the Right Prenatal Vitamin For You
When selecting a prenatal supplement, keep a few practical points in mind.
- Look for a formulation that includes key nutrients such as folate, iron, iodine and vitamin D. These are commonly recommended during pregnancy and preconception.
- Check that the product meets Australian regulatory standards. You can confirm this by looking for an AUST L or AUST R number on the label.
- Avoid unnecessarily high doses or multiple overlapping supplements unless advised by your doctor. More is not always better, particularly during pregnancy.
If you experience nausea, try taking your vitamin with food or at a different time of day. Some women find that switching formulations can also make it easier to tolerate.
Prenatal vitamins can play an important role in supporting nutritional needs during pregnancy. However, they are designed to complement, not replace, a balanced diet, regular movement and routine antenatal care.
If you’re unsure which supplement is right for you, speak with your obstetrician for tailored advice.
Frequently Asked Questions
Can prenatal vitamins make you feel nauseous?
Some women experience nausea, especially if taken on an empty stomach. Taking your supplement with food or switching formulations may help.
What if I forget to take my vitamin?
Missing an occasional dose is unlikely to cause harm. Simply resume your normal schedule the following day.
Can I take additional supplements alongside my prenatal vitamin?
It depends on your individual needs. Taking multiple supplements without medical advice may result in excessive intake of certain nutrients, so it is best to discuss this with your healthcare provider.
We’re Here To Help
If you would like to discuss your prenatal health or explore your options, we invite you to reach out using the contact form below.
