Period blood doesn't usually leak out in water primarily because the water pressure slows down the flow of blood (7,8).
Understanding the Physics of Water Pressure
When you are submerged in water, the surrounding pressure works against the flow of period blood. This pressure acts as a counterforce, making it harder for blood to escape the vaginal canal.
How Water Pressure Affects Menstrual Flow:
- Reduced Flow: The water pressure helps minimize the leakage by pushing against the exiting blood.
- Slower Movement: The blood encounters resistance as it tries to flow out, causing a reduced or halted outward flow.
Potential for Minor Leaks
Although the water pressure usually prevents significant leaks, there are exceptions. For example:
- Heavy Flow: If you have a very heavy menstrual flow, the pressure might not be sufficient to completely stop the blood.
- Sudden Actions: Coughing or sneezing can cause increased pressure, making a small leak possible. However, any leak is unlikely to be noticeable in a pool or sea.
Practical Insights:
- Tampons or Cups: If you are concerned, using tampons or menstrual cups offers added protection.
- Timing: Understanding your flow and planning accordingly can minimize any concerns.
- Don't Stress: Minor leakage is rare in water and is unlikely to be noticeable.
Summary
The primary reason period blood tends not to flow out in water is the counter-pressure from the water. While minor leaks are possible with heavy flow or sudden actions, they are usually not noticeable and generally nothing to be concerned about (7,8).
