Let me start of by saying that there is an awesome tutorial on craftster for maternity jeans, and I'm not trying to copy it. While I really liked that tutorial, and it was the basis for my inspiration to make these jeans, I wanted something a bit different.
First, I wanted the wide elastic band in my jeans rather then just solely using a t-shirt for the knit fabric to hold the jeans up. I've found that some knit fabrics tend to bag and sag pretty badly after one wearing, and I wanted something stronger holding up my jeans!
Also, I wanted to have the option of being able to have more coverage and support then just a wide elastic band. Many of the rtw maternity jeans just have that, and sometimes they don't stay up well. I've actually patterned these after a pair of jeans I had my last pregnancy from Old Navy. The elastic band is there, but there is additional knit fabric that goes up higher for more support, but it can also be folded down if desired.
One thing that's really great about converting non-maternity pants, is that they fit normally through the hips, thighs, and bottom. Most of the rtw maternity pants I've tried on sag and bag funny right under the front waistband. I hate that! These capris I've converted feel just like they used to...only more comfortable now. =) I plan to go thrift store shopping and hopefully convert some more as I need them.
Jeans that fit well though the thighs and bottom
Wide elastic for waistband
Heavy duty needle (size 100) and thread
chalk marker to mark on fabric
Here's what I did
Put the jeans (in my case, capris) on and make a mark to where they will comfortably zip up to. The pair you pick should fit comfortably through the thighs and bottom. Take them off and mark a line from your zipper mark curving up and around to the back of the pants to just under the back belt loops.
Stitch, using heavy thread on this line. You may need to stitch several time over the zipper and fly area to make it really secure. I had trouble getting my machine to sew well through some of the thick layers of denim. Using a jeans needle (size 100) and jeans thread seemed to help.
Cut off excess waistband just above your stitching line, about 5/8 inch. Try them on again for fit. If they seem big, that's ok. You need extra ease, and the elastic band will bring them in. You should be able to pull them up comfortable over your hips.
Next take your wide elastic and sew a band that fits comfortable around your lower belly about where your pants will sit. I used 2inch wide elastic, but you could use wider if desired.
Take your knit fabric and make a long tube. I made mine a bit narrower then my elastic band because I wanted it to have to stretch to go over my tummy, not just loosely fit around it.
My knit tube was about 14 inches tall before I folded it in half (see picture below) If I make these again, I will make it several inches taller because the finished band didn't go up nearly as far as I would have liked on me.
Fold your tube in half wrong sides together. Next you are going to sew a casing from the elastic. Using chalk, mark a line 2 and 5/8inches up from the raw edges. (if you use wider elastic, make your chalk line up higher)
Using a narrow zig-zag stitch (or your favorite stretch stitch) to sew along the line you marked. A regular straight stitch won't work because it will break when you stretch it to pull your jeans on and off. I'm using regular navy colored thread here.
Now you can insert your elastic between the two layers and sew the lower seam to keep it in place.
Finished band should look like this. As you can see, the elastic is sewn in a casing at the lower part of my knit fabric tube. The top is just loose, stretchy knit fabric.
Mark your center front and back, and sides, on your knit tube and pin it, right sides together, to your cut off jeans. Sew together, using a narrow zig-zag, or other stretch stitch. I sewed this seam twice for strength.
It looked like this!
I also serged that final seam to prevent fraying and make it look nicer. This is optional.
Here they are on me with the excess knit fabric folded down over the elastic band part. It would be cute to use a print fabric and then it would look like I had a cute undershirt on if it showed!
This shows it with the knit folded up for more support. I wish I would have make it several inches taller, as the line is at a funny spot on my belly and show under my shirts. Overall though, I am very happy with these pants. Like I said above, they fit like NORMAL, non-maternity jeans. I feel like I'm wearing the same capris I always wear, and that's so nice!!
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