NEW: Suu now includes Pregnancy Mode
When you're pregnant, your body doesn't just hydrate you — it hydrates your growing baby too. Your blood volume increases by up to 50%, amniotic fluid must be maintained, and your kidneys work harder than ever. All of this demands significantly more water than usual. But exactly how much — and does it change trimester by trimester? Here's what the science says, plus how Suu makes it effortless to track.
Why Water Matters More During Pregnancy
During pregnancy, blood volume increases by approximately 40–50%[1]. This extra blood carries oxygen and nutrients to the placenta and, through it, to your baby. For this to work properly, you need a significantly larger water reserve than usual.
Water also forms the base of amniotic fluid (which protects and cushions your baby), supports digestion, prevents constipation — already a common pregnancy complaint — and helps regulate body temperature. When you're even mildly dehydrated, all of these functions are compromised.
+50%
Increase in blood volume during pregnancy
800ml
Average amniotic fluid volume
+300ml
Extra daily water needed vs. non-pregnant
75%
Water content of the placenta
How Much Water Per Trimester
The American College of Obstetricians and Gynecologists (ACOG) recommends that pregnant women drink at least 8–10 cups (approximately 2–2.5 litres) of fluids per day[2]. However, this baseline shifts based on your trimester, weight, and activity level.
1st Trimester (Weeks 0–12)
2.0–2.3L
daily water target
Morning sickness may make drinking harder. Try cold water in small sips, or add lemon and ginger.
2nd Trimester (Weeks 13–26)
2.3–2.7L
daily water target
Amniotic fluid volume and blood expansion peak here — your need increases noticeably.
3rd Trimester (Weeks 27–40)
2.5–3.0L
daily water target
Baby's growth, rising metabolism, and swelling risk — highest water demand of pregnancy.
Calculate Your Personal Target
A simple formula: Pre-pregnancy weight (kg) × 30ml + 300ml (pregnancy add-on). For example, a 65 kg woman: 65 × 30 + 300 = approximately 2.25 litres/day in the first trimester. Suu's pregnancy mode calculates this automatically — just enter your details and it handles the rest.
Signs of Dehydration in Pregnancy
Dehydration during pregnancy affects both you and your baby. Watch for these signals:
Dark Yellow or Amber Urine
Your urine colour is the most reliable real-time hydration indicator. Aim for pale yellow or near-clear. Dark yellow means drink now.
Headaches and Dizziness
Headaches are common in pregnancy, but dehydration is one of the most frequent triggers. Try a glass of water before reaching for paracetamol.
Braxton Hicks Contractions
Even mild dehydration can trigger Braxton Hicks contractions. If you feel regular tightening, rehydrate first and then contact your midwife or doctor if contractions continue.
Excessive Fatigue
Pregnancy fatigue is real, but dehydration amplifies it significantly. Consistent hydration is one of the simplest ways to maintain energy throughout the day.
When to Call Your Doctor
If you haven't urinated in 8+ hours, are experiencing severe dizziness, vomiting that prevents keeping liquids down, or contractions at regular intervals — contact your healthcare provider immediately. These may indicate severe dehydration or another condition requiring prompt attention.
7 Tips to Stay Hydrated When Nausea Hits
First trimester nausea can make drinking water feel almost impossible. These strategies genuinely help:
- Go cold: Many pregnant women find ice-cold water far easier to keep down than room temperature. Try ice cubes or keep a bottle in the fridge.
- Add lemon or ginger: Both settle nausea while making water more palatable. A slice of lemon and a thin piece of fresh ginger work wonders.
- Eat your water: Watermelon (92% water), cucumber (96%), strawberries (91%) — hydrating foods count towards your daily intake.
- Anchor to routines: One glass when you wake, one before each meal, one before bed. Linking water to existing habits removes the mental effort.
- Keep a bottle visible: A water bottle you can see is a water bottle you'll actually drink from. Leave one on your bedside table, desk, and kitchen counter.
- Use Suu's smart reminders: Context-aware notifications like "You're at 35% of your goal — pick up the pace!" are far more motivating than generic alarms.
- Track your progress visually: Research shows people who measure intake hit targets more consistently. Suu's pregnancy mode shows your trimester goal and daily progress at a glance.
Suu's Pregnancy Mode
Suu now offers dedicated support for pregnant and breastfeeding women. Open the app, go to Profile → Special Conditions → Pregnancy, and Suu will:
- Automatically increase your daily goal by +300ml (base pregnancy add-on)
- Show recommended ranges by trimester
- Calculate net hydration contribution from 100+ drinks including teas, juices, and coffee
- Send smart, goal-aware reminders throughout the day
- Sync with Apple Health and Google Health Connect
Try Pregnancy Mode — Free
Join thousands of expectant mothers tracking hydration with Suu. Your personalised daily target, trimester by trimester.
Frequently Asked Questions
How much water should I drink during pregnancy?
ACOG recommends 8–10 cups (2–2.5 litres) daily as a baseline. This rises to 2.3–3 litres depending on your trimester, weight, activity level, and climate. Suu's pregnancy mode calculates your personal target automatically.
Does tea or fruit juice count towards my pregnancy water intake?
Partially. Caffeine-free herbal teas and diluted juices contribute to your fluid intake. However, caffeinated drinks (tea, coffee) have reduced net hydration due to their diuretic effect. Suu calculates the net hydration value of 100+ drinks — including all common pregnancy-safe beverages.
Is it possible to drink too much water during pregnancy?
Hyponatraemia (low blood sodium from drinking too much water too quickly) is extremely rare. Targeting 2.5–3 litres per day spread over waking hours is perfectly safe for a healthy pregnant woman. If you have a specific medical condition, consult your doctor.
Can dehydration cause early labour?
Moderate dehydration can trigger Braxton Hicks contractions. Severe dehydration may increase the risk of preterm labour in some cases, though this is not fully established by research. Staying well-hydrated is a simple, low-cost way to reduce this risk.
References
- American College of Obstetricians and Gynecologists (ACOG). Nutrition During Pregnancy. 2023. acog.org
- Institute of Medicine. Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate. National Academies Press, 2005.
- Popkin BM, D'Anci KE, Rosenberg IH. Water, Hydration, and Health. Nutrition Reviews. 2010;68(8):439–458.
- World Health Organization. Maternal Nutrition and Pregnancy Outcomes. WHO, 2020.