
First Trimester (weeks 1-12)
Baby, let’s go – what vitamins should I take when pregnant?
Jessie Day, in partnership with Zita West Products | 18 Jan 2024
Step one, know what you’re looking for on the jar, bottle or box. Or sachet. Or spray. And that’s the point, really – when picking a pregnancy supplement, the choice can be overwhelming.
Step two, in that case, is to go for a brand backed by serious expertise, who you know and trust to get quality ingredients spot on, at an effective dosage, right across pregnancy and the postpartum period. For us, it’s Zita West. And here’s why.
Looking for the Zita West discount code? TRB readers get 10% off the entire Zita West supplement range (US and UK), with code TRB10* at checkout.
Why Zita West?
For TRB founder – and IVF mum of three – Eloise, Zita West products have formed the baseline of pregnancy nutrition for all three babies.
Now expecting twins, and over halfway through her pregnancy, Eloise expects a lot from her prenatal supplements. But what is it about the globally-revered range that keeps Eloise – and myself, for the preconception products – coming back, time after time?
Zita West Products has over 20 years of experience in supporting fertility, pregnancy and postpartum nutrition and wellbeing, across a broad range of targeted supplements, backed by cutting-edge research.
We choose them, because they go beyond the basics needed for healthy pregnancy – they do that too, of course, with the NHS Recommended Folate & Vitamin D for Fertility & Pregnancy pack – and get seriously granular about the unique balance of micronutrients required to really optimise fertility, each trimester of pregnancy and the building back strong, postpartum.
This range elevates pregnancy nutritional support, with a targeted formula for each trimester. So if you’re picky – like us – about what’s in each capsule, it’s worth a deep-dive.

Upgrading your pregnancy supplements
Always ahead of the curve when it comes to the science of each product, team Zita West have announced an upgrade to their best-selling Vital Essence pregnancy supplement range, which supports mother and baby(s) across trimester 1, 2, 3 and into the fourth trimester.
What prompted this specific upgrade? Zita says,
“Our reformulation is informed (as always!) by cutting-edge research on pregnancy nutrition. These updates address specific needs for each stage of pregnancy and focus on vital nutrients such as calcium, magnesium, vitamin K, iodine and choline.
We’re proud to be at the forefront of prenatal nutrition, committed to improving and updating with the new guidance and research for maternal health. And we’re dedicated to providing the best support for both you and your baby – particularly during the critical window of the first 1,000 days, from conception to age 2.”
Another big plus for Eloise and team TRB is that the dosage across the Vital Essence Range has dropped to 2 capsules – more bang for your buck, but not as many swallows to stomach, which we know can be so tricky with morning sickness and nausea, or heartburn, further into pregnancy.
What vitamins should I take when pregnant?
Online or on the supermarket shelf, prenatals range in vitamin/mineral content and formulation. For the expert team at Zita West, micronutrients of focus here include:
- folate
- vitamin D
- essential B vitamins
- iodine
- calcium
- choline
- magnesium
- vitamin K2
- iron
- vitamin C
Note, we’ve covered the NHS guidelines for which vitamins and minerals to supplement during pregnancy – catch up here – and these cover two core players – folic acid (or folate) and vitamin D. But aside from these, where should our focus be during each trimester?
Let’s deep-dive, with team Zita West. They know the science (and experience) of each trimester, inside-out.

First trimester (early pregnancy, weeks 0-12)
The first three months of pregnancy, from the moment of conception, are often seen as the most crucial stage of development. This is the time when organs and systems are forming, plus hands, feet and limbs. And, it’s now recognised that your diet immediately before conception and in the first trimester can influence the way the embryo develops.
Superstar micronutrients to look for in your prenatal in the first trimester include:
1. Folate, for neural tube development
Folate is the natural form of vitamin B9 which we get from the food we eat, while folic acid is the synthetic form. More easily absorbed by the body, team Zita West opt for folate in all formulations across the line.
Adequate folate levels are crucial for DNA synthesis and cell division, promoting healthy egg and sperm development. And because some people may have difficulty converting folic acid to its active form, including natural folate-rich foods (think leafy greens, green vegetables like asparagus and avocados) in your diet is a great tactic during early pregnancy.
2. Niacin, for energy metabolism & nausea support
Niacin (vitamin B3) is an essential B vitamin involved in energy metabolism, this is particularly important during the rapid cell division and growth occurring in the early stages of foetal development. It can also manage nausea and morning sickness.
Check for niacin in your prenatal, and boost your dietary intake with good-quality meat and fish – poultry, tuna and salmon are great. For plant-based support, go for sunflower seeds, peanut butter, green peas, brown rice and mushrooms.
3. Iodine, for thyroid function
Iodine is a vital nutrient during the first trimester of pregnancy, as it plays a crucial role in supporting maternal thyroid function and ensuring proper development of your baby’s brain and nervous system. During pregnancy, the demand for thyroid hormones increases, and iodine is an essential component of these hormones.
So look out for iodine in your prenatal – Vital Essence 1 provides 150 mcg – and factor it into your diet with dried kelp, nori and wakame – all really tasty when sprinkled on salad, soup or noodles – good-quality dairy products and eggs.
You can tick off all three of the above with Vital Essence 1,specifically formulated to address you and your baby’s needs in weeks 0-12 of pregnancy – that often-gruelling first trimester. It’s just been reformulated too, in line with the very latest maternal health research, to feature a streamlined ingredients list, with an increase in:
- niacin (vitamin B3) – alongside the benefits we’ve covered above, research suggests that niacin might also help prevent birth defects and miscarriage
- pyridoxine (vitamin B6) – increase in the first trimester, which plays a significant role in the first trimester of pregnancy, particularly in managing nausea and vomiting

Second trimester (weeks 13-28)
This is a time of rapid growth and development, and while morning sickness may have subsided (we really hope it has!), your body is handling a spectrum of new tasks and symptoms.
Deciding whether to stick or switch up your prenatal for the second trimester? Alongside maintaining meaningful levels of iron, calcium and folate, as covered above, look out for:
1. Specific B vitamins, including B5 & B7
B vitamins play a vital role in healthy pregnancy, for mum and baby. In the second trimester, two key ones to look for in a prenatal include vitamin B5 (pantothenic acid) and vitamin B7 (biotin).
Both are crucial for healthy metabolism, ultimately contributing to sustained energy as your second trimester ramps up. And by energy, we don’t just mean keeping exhaustion at bay – although that’s part of it – but crucially the energy required at a cellular level.
B vitamins are primarily found in meat and animal produce, leafy greens and legumes.
2. Calcium, for bone formation
Calcium plays a vital role in the second trimester of pregnancy as it contributes to the development of a baby’s bones, teeth, heart and muscle. It also supports proper blood clotting and nerve function in both mother and baby.
Excellent dietary sources to pack in alongside your second trimester prenatal include sardines, dairy products like cheese, milk and yogurt – kefir is also particularly high in calcium – and leafy greens.
3. Choline, for brain development
This powerhouse nutrient is particularly essential for your baby’s brain development during pregnancy, as well as prevention of neural tube defects.
Demand increases during the second trimester, and thanks to its recent reformulation, Vital Essence 2 specifically packs in a higher dose of choline, in line with the very latest research.
Alongside factoring it in when choosing your prenatal for the second trimester, get more choline into your diet with fish – salmon is a particularly good source – and legumes, eggs, beef and poultry. Vegetables like cauliflower and brussels sprouts are also great choices.
4. Magnesium, for muscles, nerves, bones & teeth
The second trimester is an important phase for bone and teeth development, so alongside a good level of calcium, getting enough vitamin D and K is crucial, as well as magnesium.
You’ll find magnesium to be a handy tool too in maintaining a well-functioning nervous system – pesky Charlie horses and pregnancy aches and pains, as well as stress and sleep issues, can all be worked on really effectively with effective magnesium dosage.
Get more magnesium into your diet with a focus on plant sources – from nuts and seeds to spinach and dark chocolate.
Vital Essence 2 is formulated to check off all of these essential nutrients. Plus a few more, with a targeted focus on essential iodine, manganese and chromium – often missed out by prenatals, and the average dietary intake.

Third trimester (weeks 29-40+)
At this stage in your pregnancy your baby and body are all about two things – growth (and prep for the world outside), and getting ready for birth.
You’ll be looking for these key micronutrients in your prenatal (and remember to stock up for post-birth and the 4th trimester with a really great postnatal supplement too):
1. Vitamin K2, for labour & bone support
Vitamin K2 plays a key role in supporting proper blood clotting to help prepare your body for labour. It also directs calcium to the bones to ensure proper bone mineralisation.
Foods rich in vitamin K2 include chicken, cheese (particularly hard cheeses), beef mince and egg yolks, so if you’re vegan or plant-based, supplementing with a prenatal like Vital Essence 3 in your third trimester may be helpful.
2. Iron, for blood supply & oxygen delivery
Iron is crucial right across pregnancy, but during the third trimester it’s essential for expanding the blood supply to meet the increased demands of both you and your growing baby. It also supports oxygen transport, which is very important during labour, and helps prevent maternal anaemia.
So, factor iron into your search for a really good third trimester prenatal supplement, and boost your dietary intake with foods like spinach, dark chocolate, lentils and beef or sardines.
3. Vitamin C, for collagen & iron requirements
Vitamin C is crucial for collagen formation, contributing to the development of skin, bones, and connective tissues in both mother and baby. It also aids in iron absorption and supports the immune system.
Check your prenatal for vitamin C, and get a few easy boosts into your diet with your favourite fruits (guava, blackcurrants and kiwi are vitamin C powerhouses), red and green peppers, and kale.
Next on your list
- Stock up on your prenatals for trimesters 1,2,3 and 4 with our exclusive discount code TRB10* across the complete Zita West range
- Read this next – the NHS says these are the most important vitamins for pregnancy (for a solid baseline)
- Subscribe to our weekly newsletter, for more to-the-minute info and exclusive discounts and giveaways from the experts we love and trust
*TRB10 is valid once per customer only. Excludes subscription purchase. This offer cannot be used in conjunction with any other offer. Zita West terms of the site apply.