After some research, I found that rosemary is a prime ingredient in most postpartum bath soaks as it has been known to help with muscle relief, circulatory problems, as well as mental fatigue and fluid retention (source). Peppermint is one of the main ingredients in many of the athletic muscle relief gels, so adding a bit of peppermint essential oil was a given.
Here's my quick and simple recipe for a DIY Rosemary Mint Bath Soak
1 tbsp ground oats
1/2 tbsp oats
1 tsp baking soda
1/2 tbsp dried rosemary
1 tbsp epsom salts
Combine all of the dry ingredients together, then add 1 drop of peppermint essential oil. Mix well, and tie in a cloth square. I had cotton on hand, so that's what I used, tied with cotton ribbon.
To steep, simply toss your pouch into the bath while you are running the hot water. I left mine in the bath for the duration of my soak, and smushed it around a little bit to get all of the milkiness from the oats into my bath.
Now, this is a bath soak meaning that it is absolutely not for consumption. It is safe to use during pregnancy as there is not enough rosemary in the pouch to be deemed harmful or medicinal grade, however breastfeeding moms may want to skip the peppermint essential oil as mint has been known to decrease breastmilk supply.
For more information on safe herbs during pregnancy, please go here.
Other varieties of this bath soak are....
dried citrus peel
rosemary and sage
lavender and lemon essential oil