I know that herbs that are rich in silica (one if the ingredients in the balsam) are not recommended during pregnancy or breastfeeding. For this reason, I would err on the side of caution and not use it. There are safer products you can use to prevent stretch marks, such as cocoa butter, shea butter, mango butter, macadamia oil, rose hip seed oil, and vitamin E. These all work well on their own or in combination. I make a natural anti-stretch mark cream that my clients really love. You can make an easy, quick, home-made version of it yourself. 1) Place 1/4 cup Marshmallow root into a stainless steel sauce pan with 1 cups Macadamia nut oil 2)Cover and leave on the stove-top for 2 hours, on the lowest heat setting. 3)Strain and pour oil back in the pot 4) Add 1/3 cup Cocoa Butter, 1/3 cup Mango Butter, 1/3 cup Shea Butter, and 1/4 cup beeswax. Leave on lowest heat setting, and stir until the wax has melted 5)Then stir in 1 tbsp Vitamin E, 1/4 cup Rosehip seed oil, 5 ml each of Frankincence, Neroli and Sandalwood essential oils 6) Remove from heat and pour into sterile glass jars This will harden to a salve consistency. If you prefer something lighter, you can let the mixture cool in the sauce pan, then whip it in a food processor before putting it in the jars. You can purchase the oils and butters inexpensively at www.newdirectionsaromatics.com. The marshmallow root, if you don't have it locally, can be purchased at www.mountainroseherbs.com