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So, for various reasons, I only have one pair of actual maternity pants. Since I am going to have this baby pretty soon, I really don't want to spend a whole bunch of money on pants I'm only going to wear for a couple of months.
I decided to try making my own instead. I already had the supplies, and the pants came from a thrift store on their 50 cent rack, so I figured it would be no great loss if they were an utter failure. But they ended up working out pretty well (although not perfectly).
Here's how I did it, in case you want to try making your own.
First, start with a pair of pants that are too tight in the waist, but fit well everywhere else. If they're too tight around the thighs or something, this isn't going to help.
Fold them in half so the front of your pants are wrong sides together. Cut off some of the front, as shown (note: I went back and cut more off later).
Use the cut off part to cut a stretchy panel (shown on the fold). Make sure to leave room for an elastic casing and seam allowances.
Add elastic to the top of the panel.
Pin it to your pants around the area you cut out.
Stitch using a stretch stitch and you're done!
Note: These hit in front about the same level as they did before I turned them into maternity jeans. I've seen some that have the panel, and then stretch all the way around the waistband. You could try cutting off the whole waistband too, and replacing it with a yoga type waistband.