Congratulations on the new little one on the way!! What a beautiful experience!! I have 2 kiddos, and this is my experience, and a little science, about stretch marks. First and foremost, genetics is the absolute number one determinate for stretch marks. If her mom has them, more than likely she will too, if her moms are light, hers will be too. Genetics is for first determining factor. Secondly however, there are a few things you can try that may help them to not be so itchy, and afterwards, to help them lighten up a bit quicker, BrotherMat is right though, Time is the best thing. They lighten up to nearly invisible on their own. You can try any number of natural oils, Olive oil if she can stand it, works well to help maintain elasticity. Vitamin E oil is wonderful during and after pregnancy, Vitamin E oil is proven to lighten up scars substantially, and stretch marks are scars where tissues have stretched and broken. You can also make and ointment, calendula is awesome!! You can make a simple ointment that will work wonders for diaper rash as well, that is all natural, no chemicals on that new baby bum!! I use plantain ointment on my son, and the few times he's had a rash (he's usually diaperless, effectively eliminating "diaper" rash!) it takes care of it by the next diaper change.Plantain ointment is made from the plantain plant, not the banana type. Plantain is EVERYWHERE. It grows in your lawn and pops up in the cracks in the sidewalks!!What you need to do is fill a glass jar to the top with roughly chopped plantain, then fill the jar with Extra Virgin Olive Oil. Take a chopstick or pencil and poke the plantain around to remove air bubbles, air = mold. Now put the lid on the jar and keep it in a spot on your counter, out of sunlight, somewhere that won't be harmed by oil, it will leak out, I keep a towel under the jar so it's not so messy. It needs to infuse for 6 weeks. You should check it every couple of days, add more oil if it's low, remember, you're trying to keep air out, so keeping it full is important. After 6 weeks, it's time to strain the oil. I use cheesecloth, you can find it in most arts and crafts departments. You want to remove all the plant matter from the oil. The oil should be a neat green color! To make the ointment you will need beeswax. If you know of anybody that has bee boxes, you can usually get it from them. People who sell local honey can usually point you in the right direction as well, or, perhaps you already have some!! What you do is grate the beeswax, you use 1 ounce of oil to 1 Tablespoon of grated beeswax. Put the oil and beeswax together and heat gently over a low flame, a candle flame is really all that's necessary to melt the beeswax. You just want to melt the beeswax into the oil, then pour it into a glass jar to store it and use it!! If it's to thick, add more oil, if it's too thin add more beeswax. You can use this ointment for stretchmarks, diaper rash, and rash, burns, dry skin. It's really wonderful! you can also add other things to your oil infusion if you'd like to, caledula petals, yarrow, aloe vera, there are alot of great healing herbs that you can infuse the oil with!! It's best to use fresh herbs if you can!Wikipedias page on plantain, alot of pictures!!
http://en.wikipedia.org/wiki/Plantaginaceae Plantain is also called Plantago, and Plantago major is the best for medicinal purposes, but they all work!!This is the USDA plant profile for plantain, this one may help you find your local variety.
http://plants.usda.gov/java/profile?symbol=PLMA2 And if you have any questions. please don't hesitate to ask me!! Best wishes!! Love and Light!!