Suffering your period once a month is enough of an annoyance; the last thing you probably want to deal with is bleeding through your sanitary napkin or tampon and ruining your underwear, pants or bedding. Fortunately, it's not difficult to remove menstrual blood stains and retain your clothing and bedding completely stain-free.
Rinse off any particles of uterine lining from the fabric with cold water; this will promote blood in the fabric to congeal and come out of the fabric before setting. Wring the fabric to remove excess water.
Pour hydrogen peroxide directly onto the blood stain and allow it to sit and fizz for a minute or two. The fizzing is a reaction between the protein in the blood and the peroxide.
Blot at the peroxide with a cleaning rag or paper towels to lift the period blood stains out of the fabric. Rinse the fabric and repeat these steps until all of the blood is removed from the fabric.
Wet the fabric in cold water.
Create a paste with 1 tbsp. of meat tenderizer and 2 tsp. of cold water. Rub the paste into the stain with your fingers and then allow it to sit and dry for ½ to 1 hour.
Shake the dried meat tenderizer from the fabric and launder the fabric in cold water. Inspect the fabric for remnants of the period stain and repeat the above steps until all of the stain has been lifted.
Test the peroxide on a hidden area of colored or printed fabric as it has a tendency to bleach colors from fabric; you may have to dilute the peroxide or attempt other methods of removing the menstrual blood stains.