I am so excited to share this tutorial! I really hope it helps someone out there and that you guys find it useful. It’s a long and picture heavy post, so lets jump right in.
I apologize ahead of time. My phone died half way through me working on these and I switched to my actual camera, which in theory should result in better photos. It didn’t. So halfway through the tutorial you will notice that the photos become more blurry. It is not your computer screen, it is my camera.
First off, this method works best with low rise, stretch jeans. I don’t think this will work with higher rise pants as the waistband of jeans will sit too close to the waist. So you will need a pair of low rise, stretchy jeans.
- A pair of low rise stretchy jeans
- 0.5m jersey fabric – I am using good quality cotton jersey (95% cotton, 5% spandex) with good recovery. This jersey is medium weight and rather soft. I would imagine I would want something soft and comfy on my belly if I was pregnant. I recommend to match the color of your fabric to the denim you are using, but anything will do! Use up those jersey leftovers if you have them.
- 0.5cm wide elastic
- Ballpoint or Stretch needle, thread
- Seam Ripper
- Sewing Machine, Serger (if you have it, if not you can do the whole thing on sewing machine), Tape Measure, and other regular sewing supplies
Before we do anything else, we need to take some measurements. Put the jeans on and make sure you can zip up the zipper. Once the jeans are on, take two measurements – height from the base of the waistband to where you want the maternity waistband to sit and the circumference of where you want the top of the maternity waistband to be.
Asha’s measurements were height of 7 1/4″ and circumference of 29 3/4″.
Next we will prep the jeans. Using the seam ripper remove the waistband and belt loops. Keep the top of the belt loops attached to the waistband. This way nothing will get lost while you store the waist band. Here is what it looked like :
Finish the raw seam edge of the jeans in your preferred method. I used the serger, but a zigzag or faux serger seam on your sewing machine will do. I also like to give the top of the jeans a nice press here. It is so much easier to work with pressed fabric!
Now we gotta make sure that zipper stays close for the next 9 months. Pull the zipper closed and flip the zipper pull to the top. Using regular needle and thread, sew a few loops right under the zipper pull over the zipper teeth. This creates a temporary stop for the zipper and it won’t come undone.
Flip the zipper pull back down and pin the fly shut.
We gotta do one more thing before we can draft the pattern. Measure the seam allowance on the top of the jeans. You will be able to see the darker fabric where the waist band seam used to be so it is pretty easy. Don’t worry if you make your seam allowance a little bigger, it’s all good.
Using the tape measure, measure the top of the jeans. Measure the front from side seam to side seam and the back from side seam to side seam. Front will be a little shorter than the back. Asha’s measurements were 9” for the front and 23” for the back.
Onto the pattern! I started with the back piece since it was easier.
The top of the back waist band seam on the jeans was 23” (from step 4), but the jersey has quite a bit of stretch, so it needs to be slightly less than that. I settled for the back width of 21”. Asha’s height measurement was 7 ¼” (from step 1).
I added ¼” seam allowances on the top and sides, and for the bottom I added ½” seam allowance, which matches the seam allowance on the top of the jeans’ waist band.
This resulted in the final measurement of my back piece being 21.5″x8″.
For the front piece, I wanted to add a slight ruching on the sides so the fabric can accommodate the growing belly better. To do this, I multiplied my measured height of 7 1/4″ by 1.5 and got 10 ¾ “. The width of the front of the waist band on the jeans was 9” and I took it down to 8”.
Adding seam allowances of ¼” on top and sides and ½ on the bottom, resulted in my final piece measurement of 11.5″ x8.5″.
Cut your pattern pieces out of the fabric. You will need two fronts and two backs.
Since the design involves rouching on the sides of the front panels, I basted two gathering stitches (maximum length of regular stitch) on the sides of my front panels. To gather them, pull the bobbing threads.
Note that you don’t have to do this if you are comfortable with working with knits. You can just pin your fronts and backs together and stretch the back piece as you sew.
Pin front pieces to the back pieces and sew them together. Pull the gathering threads out if you’ve used them. Turn both pieces out and give them a nice press, pressing the seams out towards the back. Here is what my pieces looked like after all of that:
We are going to attach the two waist bands together. With right sides facing each other, match up the side seams on one of the raw edges of the waistbands. Pin them together and sew. Here is mine all serged together.
We are going to attach an elastic to the top of the waistband for some extra staying power. Asha’s measurement for the circumference of her lower ribcage, where the waist band would sit, was 29 3/4″ (step 1). My elastic was pretty stiff so I cut 28″, but this will vary with the elastic you use. If you are making the pants for yourself, I recommend measuring the elastic by stretching and wrapping it around where the waist band would be, until it is comfy, and cutting ~1/2″-3/4″ more than what you measured. The extra is for the overlapping seam in the elastic when you attach it.
Divide your elastic into quarters and mark them with pins. Do the same with the top of your waist band. Pin the elastic to the waistband in quarters. I find this is the easiest method, as I stretch the elastic as I sew it on.
Using a regular zig zag stitch attach the elastic to the seam allowance on top of the inside of the waistband.
Turn your waistband out and give it a press.
Pin the lower unfinished edges of the waistband together and finish it in your preferred method. I used my serger, but you can use a regular zig zag or faux serger seam.
Last step! We are going to attach the waist band to the jeans. Align the side seams on the waistband and the jeans and pin the two together with the waist band lying outside of the jeans. This way the seam is on the inside.
Sew the two together using a stretch stitch. I used stitch that looked like a triple stitch, but a lightning bold looking stitch will also do.
Once attached, flip the waistband up and press the seam allowances up towards the waistband. Sew a zig zag seam around the bottom of the waist band, catching the seam allowance on the inside. This will keep the seam allowances lying flat and from flipping around causing all kinds of discomfort.
You are done! Here is what they look like all finished:
Wear them proudly and be comfy because they will accommodate your growing belly.
When you need to convert the jeans back to their pre-maternity state, detach the maternity waist band and sew the regular waist band back on. If you’ve made jeans before, it will be even easier!
Let me know what you think and if you have any questions!
P.S. Now I want to make myself a pair of these, purely as buffet / Christmas Dinner pants…