How to Have a Healthy Pregnancy: The Ultimate Trimester-by-Trimester Guide

A healthy pregnancy in Australia is one where you eat a varied, mostly whole-food diet; take folic acid and iodine supplements; attend regular antenatal appointments with a midwife, GP or obstetrician; stay physically active most days; avoid alcohol, smoking and high-mercury foods; and pay attention to your mental wellbeing. There's no perfect formula — just consistent, sensible choices.

Pregnancy is calculated from the first day of your last menstrual period and lasts roughly 40 weeks, divided into three trimesters of about 13 weeks each. According to Pregnancy, Birth and Baby, the basics of looking after yourself stay largely the same throughout — but the priorities shift as your body and baby change.

It's also worth dropping the idea that pregnancy needs to be a project of perfection. Eating a sausage roll because you couldn't face anything else for a week of morning sickness will not undo your baby's development. The headline is consistency, not flawlessness.

What is worth being deliberate about is the small list of things with strong evidence behind them: folate, iodine, food safety, alcohol, smoking, regular check-ups, gentle daily movement, and asking for help when something feels off — emotionally or physically.

Before you're pregnant — or in the very early weeks before you know — three things matter most: starting a folic acid and iodine supplement, getting your routine vaccinations up to date, and booking a pre-conception check with your GP. These steps reduce the risk of neural tube defects, protect against preventable infections, and flag any health conditions worth managing early.

The Australian recommendation, supported by the Department of Health and your GP's standard advice, is to start a folic acid supplement of at least 500 μg (0.5 mg) per day for one month before conception and continue through the first trimester. Folate dramatically reduces the risk of neural tube defects like spina bifida, and most damage is done before many people even realise they're pregnant.

A few other practical things to handle in the months before trying:

• See your GP for a pre-conception check, including a review of any current medications. Some prescriptions need swapping out before pregnancy.
• Update vaccinations — particularly whooping cough, flu, and MMR (measles-mumps-rubella) where needed. Some live vaccines can't be given during pregnancy, so timing matters.
• Have a dental check. Hormonal changes during pregnancy can worsen gum issues, and most state health systems offer pregnancy dental care.
• Cut back on alcohol and quit smoking or vaping if either applies. Both directly affect fertility as well as fetal development.
• Aim for a healthy weight range before conceiving where possible — this lowers the risk of gestational diabetes and pre-eclampsia.

If you're already pregnant and reading this thinking "I didn't do any of that," don't panic! Most people's pregnancies are completely unplanned, and a healthy outcome is still very much the norm. Start the supplements today, book the GP appointment this week, and move forward.

The first trimester is about three things: nailing your nutrition (especially folic acid and iodine), booking your first antenatal appointments, and surviving the symptoms — nausea, exhaustion, sore breasts, and food aversions can all hit hard. Most pregnancies feel hardest in this stretch, partly because you're often keeping the news quiet while feeling rough.

Your first antenatal appointment is usually booked between weeks 8 and 10. By around week 11–13 you'll be offered a first-trimester combined screening test (the nuchal translucency ultrasound and blood test), and many people choose to add non-invasive prenatal testing (NIPT). Your care team will also run a routine blood panel, urine test, and discuss your model of care — public hospital, private obstetrician, midwifery group practice, or shared care with your GP.

Nutrition is the biggest lever in the first trimester. Continue your prenatal multivitamin (or take folic acid plus iodine separately), aim for a varied diet across the five food groups, and stay well hydrated. According to Pregnancy, Birth and Baby{:target="_blank"}, the safest caffeine intake during pregnancy is no more than 200 mg per day — that's roughly two espressos, three cups of instant coffee, or four cups of medium-strength tea. Energy drinks are best avoided entirely.

Morning sickness affects most people to some degree, despite the misleading name (it can hit any time of day). What tends to help:

• Smaller, more frequent meals rather than three big ones — an empty stomach often makes nausea worse.
• Bland, carb-heavy snacks like dry crackers, toast or rice cakes by the bed for the first 10 minutes of the morning.
• Ginger in tea, capsule or lolly form has reasonable evidence for mild-to-moderate nausea.
• Vitamin B6 supplements — talk to your pharmacist or GP before starting.
• Staying well hydrated, even if it's small sips throughout the day.

If you can't keep fluids down or you're losing weight, see your GP or midwife. Hyperemesis gravidarum is more than just bad morning sickness and there are effective treatments.

You'll also want to start thinking about food safety — soft cheeses, deli meats, raw seafood, and high-mercury fish are the main risks. We've covered the full list in the dedicated section further down this guide.

The second trimester is often called the "honeymoon" of pregnancy. Energy returns, nausea usually settles, and you start to feel — and look — visibly pregnant. This is the window for big-picture preparation: anatomy scan, glucose screening, registry, nursery planning, skin care, and starting to think about the practical side of life with a newborn.

The 20-week morphology scan is the major medical milestone of the second trimester. It checks your baby's growth, organ development, and placental position. Around weeks 24–28 you'll also be offered a glucose tolerance test to screen for gestational diabetes, which the Australian Diabetes Society estimates affects 12–14% of Australian pregnancies.

This is also when most parents start their baby registry, with the second-trimester sweet spot typically falling between weeks 18 and 28 — early enough to give friends and family time, late enough to know what you actually need. If you're not sure how to approach it, our guide on how to create a baby registry for your lifestyle walks through what to add, what to skip, and how to think about it without feeling like you're writing a shopping list to the moon.

A few other priorities for these months:

• Skin care. Your skin will likely change — pigmentation, dryness, sensitivity, and the linea nigra often appear in the second trimester. Some active ingredients (like retinoids and high-dose salicylic acid) aren't recommended during pregnancy. Our complete guide to pregnancy safe skin care covers what to swap and what to keep.
• Maternity clothing. Most people grow out of their pre-pregnancy waistbands somewhere around weeks 16–20. A small, well-chosen capsule of maternity wear — a few pairs of stretchy bottoms, two or three tops that fit, a supportive bra and a belly band — gets most people comfortably through to birth without overspending.
• Move your body regularly. Energy levels make this the easiest trimester to build a sustainable routine — walking, swimming, prenatal yoga or Pilates are all great.
• Start birth education. Hospital antenatal classes typically run in the second or early third trimester. Book early; popular weekend slots fill fast.
• Think about leave. This is also a good time to confirm your parental leave entitlements with your employer and Services Australia.

The third trimester is the home stretch — a mix of nesting energy, growing fatigue, and the very real physical reality of carrying a near-full-term baby. The priorities now are rest, recognising warning signs, finalising hospital prep, and keeping your mind as well-rested as your body. Antenatal appointments become more frequent, and your team will be watching for any signs of pre-eclampsia, growth concerns, or reduced movements.

From around week 28 you'll move to fortnightly appointments, and from week 36 to weekly. At each visit your midwife or obstetrician will check your blood pressure, urine, baby's growth, position, and heart rate. From the third trimester onwards, you should also start tracking your baby's movements daily — most parents notice a regular pattern, and any significant change is worth ringing your hospital about.

Sleep gets harder. Hormonal changes, an active baby, frequent toilet trips, heartburn, and the simple physics of a third-trimester belly all conspire against good rest. A few things that genuinely help:

• A wedge pillow or full pregnancy pillow to support your bump and align your hips.
• Sleeping on your left side — the standard recommendation in the third trimester, as it improves blood flow to the placenta.
• A consistent wind-down routine, screens off about an hour before bed, and keeping the bedroom cool.

For more on this — including positions, products, and managing 3am insomnia — see our guide on how to sleep comfortably during the third trimester.

The other major third-trimester job is preparing for the hospital. Most people aim to have their bag packed by week 36, given that "full term" is anywhere from 37 to 42 weeks. Our ultimate hospital bag checklist for mum and baby breaks down what you'll actually use (versus what gets recommended on every list and stays untouched in the bag).

A few other things worth ticking off in these final weeks:

• Install the car seat or capsule by around week 36 and have it checked by a Type 1 accredited installer.
• Wash and prep newborn clothes, blankets and wraps — a baby-safe detergent makes a difference for sensitive skin.
• Stock the freezer with easy meals.
• Discuss your birth preferences with your team, but stay flexible.

Know the warning signs: reduced movements, severe headaches, vision changes, sudden swelling, vaginal bleeding, or persistent abdominal pain — call your hospital, day or night.

The short list of things to avoid during an Australian pregnancy is alcohol, smoking and vaping, recreational drugs, certain high-risk foods (raw or undercooked meat and seafood, soft cheeses made from unpasteurised milk, pre-prepared salads, deli meats, pâté, and high-mercury fish like shark, marlin and broadbill), excess caffeine over 200 mg a day, and certain skincare and medication ingredients without medical clearance.

The Food Standards Australia New Zealand (FSANZ) listeria advice is the gold-standard source for the food safety side. The headline risks are listeria (rare but serious), salmonella, and methylmercury exposure from large predatory fish.

A few of the most-asked specifics:

• Soft cheeses like brie, camembert, ricotta and feta are fine if cooked through (e.g. on a hot pizza), but should be avoided cold from the deli.
• Smoked salmon, sushi and sashimi are best avoided due to listeria risk. Cooked sushi (teriyaki chicken rolls, tempura prawn) is fine.
• Eggs should be cooked until the white and yolk are firm — no runny yolks, raw mayo, mousse, tiramisu or Caesar dressing.
• Coffee and tea are fine within the 200 mg caffeine limit. Decaf is unlimited. Most herbal teas are fine but check with your pharmacist for anything unusual.
• Alcohol has no known safe level during pregnancy, per the Australian Guidelines from the National Health and Medical Research Council.

For a printable, comprehensive list — including portion guides for fish, soft serve ice cream rules, and the lowdown on hot chips — see our full guide to the foods to avoid during pregnancy.

Staying active and protecting your mental health are two of the most underrated parts of a healthy pregnancy. Australian guidelines recommend 2.5 to 5 hours of moderate-intensity activity per week during a healthy, low-risk pregnancy — and ongoing mental wellbeing checks are now a standard part of antenatal care, with around 1 in 5 Australian women experiencing perinatal anxiety or depression.

On the physical side, walking, swimming, prenatal yoga, prenatal Pilates, light strength training, and stationary cycling are all generally safe through all three trimesters for low-risk pregnancies. The Better Health Channel recommends avoiding contact sports, activities with a high fall risk (skiing, horse riding), scuba diving, and from the second trimester, any exercise that involves lying flat on your back for long periods.

A few practical guidelines:

• You should be able to hold a conversation while exercising — if you can't, ease off.
• Stay hydrated and avoid overheating, especially in the first trimester.
• Listen to your body. Pelvic pain, dizziness, or shortness of breath beyond what you'd expect are reasons to stop and check in with your healthcare provider.
• Pelvic floor work (gentle daily activations) is one of the best investments you can make for both birth and postpartum recovery.

On the mental health side, pregnancy is a huge life transition, and feeling anxious, ambivalent, weepy or just not yourself is incredibly common — and not a sign you'll be a bad parent. Beyond Blue has free, confidential support specifically for the perinatal period, and most antenatal teams now use a screening questionnaire (usually the EPDS) at multiple points during pregnancy.

If something feels off — persistent low mood, intrusive thoughts, panic, sleep that doesn't recover even when you're physically rested, feelings of dread about the baby — say so. Your midwife, GP, or obstetrician can help, and there's no judgment in the room. Talking to your partner, a friend, or a perinatal counsellor early is often the difference between a hard fortnight and a much harder six months.