It’s Not Just Thirst

When you’re pregnant and waking up with headaches, feeling foggy by midday, or nauseated without any clear reason, it might not just be hormones. It could be dehydration,  and not the kind that leaves you parched and reaching for a bottle of water. We’re talking about subtle, persistent fluid loss that chips away at your energy, focus, and wellbeing without waving red flags.

Many women mistake the symptoms of dehydration in pregnancy for normal discomforts or simply being tired. But these symptoms can escalate quickly, and what feels like "just part of the journey" might actually be your body asking for help.

Why Hydration During Pregnancy Matters More Than Ever

Pregnancy changes everything,  including how your body uses water. Your blood volume increases by up to 50%, your kidneys work overtime, and amniotic fluid needs constant replenishment. According to the NHS, staying well hydrated during pregnancy is essential to support increased blood volume, amniotic fluid levels, and overall maternal wellbeing. While there’s no strict UK guideline on exact fluid intake, aiming for around 6–8 glasses (1.5–2 litres) per day is generally recommended, with more needed in hot weather or when experiencing vomiting or diarrhoea. 

Yet studies show that 1 in 3 pregnant women don’t meet their hydration needs. 

Without enough fluids:

• Your digestion slows
  
  

• Fatigue worsens
  
  

• Headaches become more frequent
  
  

• Muscle cramps and joint pain increase
  
  

• You’re more prone to urinary tract infections
  
  

• Braxton Hicks contractions may intensify
  
  

The Overlap Between Dehydration and Pregnancy Symptoms

Here’s why dehydration gets missed so often: it mimics the very symptoms we’re told to expect during pregnancy.

This overlap makes it easy to ignore hydration as a root cause. Even worse? When you’re already nauseated, drinking water often makes it worse.

Why Plain Water Isn’t Always Enough

Many women are told, "Just drink more water." But when you're already feeling sick, or constantly peeing, plain water can actually make symptoms worse by diluting electrolytes.

Electrolytes,  minerals like sodium, potassium, and magnesium,  are vital for nerve function, fluid balance, and muscle coordination. During pregnancy, they help regulate your blood pressure, support fetal development, and reduce leg cramps and headaches.

Low electrolytes can feel like anxiety, exhaustion, or a looming migraine.

What you need: Smart hydration. That means sipping fluids that include electrolytes and are designed for pregnant bodies,  not just repurposed sports drinks.

Real Stories, Real Symptoms

Darcey, the founder of ISOMUM and a practising midwife, recalls how often women would arrive at maternity triage convinced something was seriously wrong, with elevated heart rate, lightheadedness, and nausea, only to discover they were simply dehydrated. “It was startling how often it happened,” she shares. “We’d see women with symptoms that looked like pre-eclampsia, and it turned out to be dehydration.”

One of Isomum's customers, Alice, 32, shared:
"I kept thinking I was just really tired or if I was getting ill. My legs ached, and I couldn’t focus. It wasn’t until my midwife suggested I try an electrolyte drink that things clicked. Within a day, I felt like my brain came back online."

The Science of Hydration and Maternal Health

A growing body of research connects hydration to maternal health outcomes:

• Dehydration increases the risk of neural tube defects, low amniotic fluid, and preterm labor. [Source]
  
  

• Even mild dehydration reduces cognitive performance, mood, and memory in women. [Source]
  
  

• Hydration affects blood pressure regulation, a key concern in preventing hypertensive disorders during pregnancy. [Source]
  
  

How to Know If You're Dehydrated (When You're Pregnant)

Beyond thirst, look out for these signs:

• Dark yellow urine (ideal: pale straw colour)
  
  

• Dry mouth or lips
  
  

• Headaches or pressure behind the eyes
  
  

• Feeling woozy when standing up
  
  

• Trouble concentrating
  
  

• Rapid heart rate
  
  

If you’re unsure, try this 3-day hydration self-check:

(1 = low energy/fog/dark urine, 5 = high energy/clear urine/no fog)

Notice a trend? It might be time to rethink how you're hydrating.

Safe Solutions That Actually Work

Not all hydration products are created equal. Some are packed with sugar, caffeine, or ingredients that aren’t safe in pregnancy. Here’s what to look for:

• Backed by clinical insight (preferably from maternal health experts)
  
  

• Contains essential electrolytes like sodium, magnesium, and potassium
  
  

• No artificial dyes, excess sugar, or stimulants
  
  

• Safe for pregnancy and breastfeeding
  
  

• Gentle on the stomach
  
  

This is where Isomum steps in. It’s the only hydration formula developed by a midwife specifically for pregnant and postnatal women. It’s low in sugar, easy on nausea, and formulated to restore what your body actually needs.

• Clinically informed

• Backed by midwifery expertise

• Created for mothers, not athletes, (unless you count growing a human as the ultimate endurance sport!).

Learn more about how Isomum supports your hydration journey here.

When to Seek Medical Support

While mild dehydration can be corrected with rest and hydration, call your midwife or GP if you experience:

• No urination for over 8 hours
  
  

• Inability to keep fluids down
  
  

• Dizziness that doesn’t improve
  
  

• Signs of preterm labour (e.g., contractions, back pain)
  
  

Don’t ignore your body’s signals. You’re not being dramatic. You’re being proactive.

It’s Time We Took Hydration Seriously in Pregnancy

Hydration is not a luxury or an afterthought. It’s a core part of maternal wellness. When we stop telling women to "just rest" and start giving them tools that actually work, we shift the narrative from survival to support.

You deserve to feel strong, clear, and seen during pregnancy.

Try Isomum today, hydration with purpose.

P.S. Want to stay ahead of pregnancy fatigue and fog?
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