Swimming and Water Exercise During Pregnancy

Your belly is growing, your back aches, and your shoes feel tight. But in the water, you're almost weightless. Swimming is one of the few forms of exercise where your body actually feels lighter the further along in pregnancy you get.

Water supports up to 90 percent of your body weight. That means less strain on joints, pelvis, and back — exactly the areas that trouble most pregnant women. At the same time, the water provides natural resistance that strengthens your muscles without overloading your body.

Here's everything you need to know to exercise safely in water throughout your entire pregnancy.

Why swimming is perfect for pregnant women

Swimming offers a unique combination of benefits that few other forms of exercise can match:

Relief: The buoyancy of the water takes the weight off your belly, pelvis, and back. Many pregnant women find that pain and discomfort disappear entirely while in the water.

Cardiovascular fitness: Swimming is a full-body workout that maintains fitness without hard impact. The heart and lungs work efficiently.

Swelling: Water pressure pushes excess fluid back into the bloodstream. Many notice that swollen legs and ankles improve after a swim.

Pelvic pain: Women with pelvic girdle pain (symphysis pubis dysfunction) can often swim when they can't walk. The water stabilizes the pelvis.

Sleep: Moderate water exercise can improve sleep quality, which is often challenging during pregnancy.

Mood: Like all exercise, swimming releases endorphins. In addition, the quiet, rhythmic movement through water has a meditative effect.

Trimester by trimester

First trimester (weeks 1–12)

In the first trimester, you can swim as normal, provided you have the energy for it. Nausea and fatigue mean many have little energy.

• Swim at your own pace
• Listen to your body — if you're tired, take breaks
• Drink water (you sweat even when in the pool)
• Avoid overheating — stick to heated pools, no sauna afterwards

Second trimester (weeks 13–27)

Many find this is the best period for swimming. The nausea has eased, energy has returned, and your belly isn't too large yet.

• Increase activity somewhat if you feel good
• Try different strokes — backstroke and sidestroke are nice alternatives to freestyle
• Use a kickboard for variety
• This is a good period for aqua aerobics classes

Third trimester (weeks 28–40)

Your belly is large, breath is short, and everything feels heavy — except in the water. Many pregnant women find the third trimester is when swimming brings the most joy.

• Breaststroke can cause pelvic discomfort — switch to sidestroke or backstroke
• Shorter sessions (20–30 minutes) may work better than long ones
• Use a pull buoy between your legs to reduce pelvic strain
• Gentle swimming and water walking are just as good as intervals

Strokes and exercises

Breaststroke

The most popular stroke for pregnant women. But be aware: the frog-like leg kick can strain the pelvis in the last trimester. If you notice discomfort, switch to another stroke.

Backstroke

Good for relieving back strain. Note that some pregnant women may feel dizzy from lying on their back from week 28 onwards. If this happens, roll onto your side.

Sidestroke

A gentle stroke that is easy to learn and relieves the pelvis. Perfect for the third trimester.

Freestyle (front crawl)

Works well for those who already have the technique. Can become challenging with a large belly, but many swim freestyle all the way to their due date.

Water aerobics

Many pools offer dedicated classes for pregnant women. These include:

• Strength exercises with water resistance
• Cardiovascular training
• Pelvic floor exercises
• Relaxation and breathing exercises
• Social connection with other pregnant women

Safety and precautions

General safety tips

• Water temperature: Stick to pools between 28 and 34°C (82–93°F). Avoid hot tubs above 38°C (100°F) and saunas
• Hygiene: Shower before and after swimming. Wear pool shoes in the changing room
• Stay hydrated: Drink water before, during, and after your workout
• Avoid diving and jumping: The impact on your belly from diving can be too great
• Walk carefully: Pool edges are slippery. Wear non-slip shoes

When to avoid swimming

Talk to your midwife or doctor before swimming if you have:

• Ruptured membranes or bleeding
• Risk of preterm labor
• Placenta previa
• Severe preeclampsia
• Multiple pregnancy with complications
• Been advised to rest

Open water swimming

If you prefer outdoor swimming, keep these things in mind:

Sea or lake swimming

• Check that the water is clean before entering
• Enter the water gradually — temperature shock can cause cramps
• Always have someone with you
• Stay close to the shore
• Avoid rivers or areas with unpredictable currents
• Check water quality for algae or bacteria, especially in summer

Cold water/ice swimming

Cold water immersion is not recommended during pregnancy. The sudden cold can cause a spike in blood pressure and cramping. Stick to heated pools.

Equipment you need

You need minimal equipment:

• Swimsuit: Find one with room for a growing belly. Many brands make dedicated maternity swimsuits, but a regular suit in a larger size works too
• Swimming goggles: Protect your eyes from chlorine
• Pool shoes: Prevent slipping in the changing room
• Water bottle: Keep it at the poolside
• Optional: Kickboard, pull buoy, or flotation devices for exercise variety

A sample swimming session

Here is a simple 30-minute session adapted for pregnant women:

1. Warm-up (5 min): Easy swimming, any stroke
2. Main set (20 min):
   • 4 lengths breaststroke (easy)
   • 4 lengths backstroke
   • 2 lengths leg work with kickboard
   • 2 lengths arm work with pull buoy
   • 4 lengths choice of stroke
3. Cool-down (5 min): Water walking or easy backstroke with focus on breathing

Adapt the length and intensity to how you feel. Some days 15 minutes is enough. Other days you might swim for 45 minutes. Your body will tell you what's right.

Frequently asked questions

Is it safe to swim in a chlorinated pool during pregnancy?

Yes. Chlorine levels in public pools are regulated and pose no risk to pregnant women or the fetus. Shower after swimming to rinse chlorine off your skin.

Can I swim all the way to my due date?

Most women can swim right up until labor starts, as long as the pregnancy is uncomplicated. Many find that swimming at the end of pregnancy is the only thing that provides pain relief. Talk to your midwife.

How often should I swim?

2–3 times per week is ideal, but once a week is better than none. Start with short sessions and increase gradually.

Can swimming trigger contractions?

No, there is no evidence that swimming triggers contractions. On the contrary, the relaxing effect of water can calm irregular practice contractions (Braxton Hicks).

What if I can't swim?

Water walking and aqua aerobics provide many of the same benefits without needing to know how to swim. You just need to stand in the water (chest-deep) and do exercises.

Sources

1. WHO — Physical activity guidelines during pregnancy
2. American College of Obstetricians and Gynecologists (ACOG) — Exercise in water during pregnancy
3. American College of Nurse-Midwives