What to Know About Drinking Water During Pregnancy

Medically Reviewed by Dany Paul Baby, MD on May 31, 2022
Written by Sharlene Tan
4 min read

When you're pregnant, drinking water is important for yourself and for your baby. Find out more about hydration during pregnancy.

Water makes up 60% of your body. Water is essential because it.

  • Regulates your internal body temperature
  • Builds your cells
  • Transports proteins and carbohydrates via your bloodstream
  • Lubricates your joints
  • Flushes waste from your system
  • Forms your saliva
  • Acts as a shock absorber for your spinal cord and brain

You lose water all the time, though, through regular body processes, including:

  • Sweating
  • Production of urine
  • Bowel movements

You’ll lose even more water when you:

  • Are at higher altitudes or are outdoors during extreme temperatures
  • Are sick
  • Are more physically active 

During pregnancy, though, your body needs more water to:

  • Produce more blood 
  • Promote your baby’s blood circulation
  • Form amniotic fluid, which is the liquid that surrounds your baby 

Constipation is a common problem during pregnancy. Taking iron supplements can make constipation worse. Drinking more water may help relieve your constipation.

Most municipal water has fluoride. This mineral helps in the development of your growing baby’s bones and teeth.

Experts say that pregnant women should drink 8 cups to 12 cups of fluids a day. This equals about 64 ounces to 96 ounces (1.9 liters to 2.8 liters), or a handful of 16.9-ounce disposable water bottles.

A person’s water needs can be calculated based on how much food they need a day. Adults need about 1 milliliter to 1.5 milliliters of water for each calorie they eat.

Your water needs, meanwhile, increase as your pregnancy progresses. So, in early pregnancy, you don’t need to worry about having to drink a lot more water, but you still need to be aware of how much you’re drinking. Like many pregnant women, you may find it hard to keep your food down in your first trimester. When you vomit, you also lose water. To make up for this, try to sip on water or ginger ale throughout the day.

In rare cases, morning sickness can be so severe that it leads to hyperemesis gravidarum. This occurs when you have such severe nausea and vomiting during pregnancy that it leads to a loss of more than 5% of your pre-pregnancy body weight or serious dehydration. This may require hospitalization.

During your second trimester, your morning sickness may be gone, but you’ll still need to start increasing your fluid intake. Doctors recommend that you eat an additional 340 calories a day, which means that you’ll need at least an extra 340 milliliters (11.5 ounces) of water a day.

When you’re in your third trimester, you’ll need 450 more calories above the regular daily recommended amount. This means you’ll need an extra 450 milliliters (about 15 ounces) of water a day.

If you don't drink enough water during pregnancy, you’ll be dehydrated. This means your body is losing more water than you’re taking in. Signs of dehydration include:

  • Urine that’s dark-colored
  • Urinating less frequently
  • Extreme thirst
  • Dizziness
  • Fatigue
  • Confusion

Mild dehydration may affect your memory or your mood. It may also impact how well you process information. Mild dehydration symptoms usually go away after you drink water, but you may need medical help if you have severe or consistent dehydration. 

Dehydration during pregnancy may affect the levels of your amniotic fluid. Oligohydramnios occurs when you have low amniotic fluid. Amniotic fluid is important, as it:

  • Protects your baby from infection
  • Protects your baby’s movements in the womb
  • Keeps your baby’s body from compressing the umbilical cord
  • Helps regulate your baby’s temperature
  • Helps develop your baby’s respiratory and digestive system

The signs of low amniotic fluid may not be obvious to pregnant women, but your doctor may run an ultrasound to check on your uterus if:

  • Your baby isn’t moving often enough
  • You feel fluid leaking from your vagina
  • You’re not gaining enough weight 

Dehydration may also cause other complications during pregnancy. This includes:

  • Swelling
  • Birth defects
  • Kidney stones
  • Urinary tract infections, which may lead to preterm labor and birth

Although it is not as common as dehydration, it may be possible to become overhydrated. People with the following health conditions are at a higher risk for overhydration:

  • Heart problems
  • Kidney problems
  • Liver problems
  • Thyroid disease
  • If you take medicines that make you retain water, like some antidepressants, opiate pain medications, and non-steroidal anti-inflammatory drugs (NSAIDs)

Talk to your doctor to find out the amount of water that's right for you during pregnancy.

Here are some ways to help you drink more water:

  • Listen to your body. You should drink enough fluids so that you don’t feel thirsty often.
  • Exercise. Try to stay out of the heat, though. Exercise early or late in the day, or exercise indoors.
  • Use soups, milk, juice, and herbal tea to increase your fluid intake.
  • Eat more vegetables and fruits, not just for a well-balanced diet, but also because they contain water too.
  • Infuse your water with fruits like lime and frozen berries to make it more appealing.
  • Carry a refillable water bottle wherever you go.

You get about 20% of the water you need from the food that you eat, so try eating more foods that are high in water content. Foods that have 90% to 100% water content include:

  • Vegetables like cabbage, celery, and spinach
  • Fruits like watermelon, cantaloupe, and strawberries
  • Drinks like fat-free milk and water

Foods with 70% to 89% water content include:

  • Dairy products like ricotta cheese and yogurt
  • Fruits like grapes, pears, and oranges
  • Vegetables like avocados and carrots