I thought it might be useful to share the process of adapting a sloper pattern to actual body measurements, and what more extreme sport version of this could I do than showing how I adjusted my usual sloper size to fit the ever shifting, radical transformations of the pregnant bod? Things have shifted, swollen, and rapidly expanded in ways that I have never drafted for before. These changes are specific to certain body parts, so simply sizing up till something fits wouldn’t give me anything that fits my actual skeletal structure. I have to bust out the scissors, tape, scrap paper, and all the best swear words I learned from my time in the restaurant industry for this transformation.
I’m starting with my high bust measurement, which pre-pregnancy was 36″. (With swelling and rib cage expansion as everything gets displaced upward, my current measurement is *slightly* larger, but I’m choosing to disregard the slight discrepancy since the bones of my neck, shoulders, and upper chest are still basically the same. These bony structures are the place that most garments will hang from, so I’m choosing to prioritize this over the softer fleshy areas that have slightly swollen (or vastly expanded) where adjustments are easier to make because fewer planes of the body are intersecting.
After printing and assembling the sloper, I’m using my Body Measurements for Sloper Comparison worksheet to record the sloper measurements and my own body measurements.
First, I check the vertical positioning of my front waist length, back waist length, and bust position. For my size, the front waist length of the sloper (taken from the high point of the shoulder to the waistline) is approximately 16.25.” My body measurement from high point shoulder to the area previously known as my waistline is approximately 15″. Since this is imprecise at best given my current shape, and because I know I’ll need additional length in the bodice front to cover my baby bump, I’m choosing not to adjust the waist position.
For the back waist length, the sloper measurement is approximately 16.75″ and my body measurement is 17″, so I’m not going to make any adjustments here.
For the bust position, I measure the pattern from the high point shoulder to the bust point/apex/nipple, and the measurement is 9.5″. My actual body measurement is 10.5″, so for this area, I’m cutting the entire dart area out and shifting it 1″ lower and redrawing the side seam, and comparing to make sure the length still matches the back side seam length.
Then I move on to the horizontal girth measurements, where things get really intense. The total waist circumference of my sloper is approximately 30.5″. My body measurement is about 41.5″ right now. The sloper measurement includes .5″ total ease at the waist for this size, so my total desired waist circumference in my adjusted sloper should include .5″ over my body measurement as well, so the total width of my personal sloper after adjustment should be 42″ total. The majority of that difference is in the front of my body, so when adjusting the sloper, most of the adjusting will be taking place in the front. From previous pattern work, though, I do know that my waist is proportionately larger than most patterns’ standard sizing, so for the sake of balanced distribution, I will add a bit to the back waist width as well.
The front waist measurement of the sloper is 16″, .25″ of which is ease, and my body measurement is 23.75″, which is 7.75″ of difference. If I add .25″ of ease, the total front adjustment I need is 8″. (I want to maintain at least about a half inch of wearing ease in my pattern, I want to be sure to add about a half inch over my total body measurement at the waist.)
24″ actual body and ease – 16″ sloper measurement = 8″ adjustment needed to full front bodice at the waist.
So I’ll be adding 8″ of extra width to the front waist, total. Since I’m working with the pattern piece that covers a quarter of the body, I’ll only be adding 4″ to the actual pattern piece. (All of these changes will be doubled in the actual fabric since this piece is cut out twice.)
For the pregnancy shape, the front waist darts are definitely not needed, (unless you’re going for something super fitted at the underbust, in which case you could shorten the dart to the length needed and end it higher, well above the waist). For my current purposes, I don’t need the dart at all. It’s 1″ wide at the waistline, so eliminating this dart adds 2″ of total width to the front bodice, or 1″ of the needed 4″ width in the quarter body pattern piece.
I still need to add 3″ to the quarter body front bodice piece, or 6″ to the full front bodice, at the waist. To determine where and how to add this extra width, I’m going to consider what amount I need for the back as well. The sloper measurement is 14.5″ in back, which is .25″ ease. My body measurement at the back waist is 17.75″. If I add .25″ to that body measurement for ease, the width I want the back waist to be is 18″. So for the back, the total adjustment I need is going to be:
18″ actual body and ease – 14.5″ sloper measurement = 3.5″ adjustment needed to full back bodice at the waist.
This means I’ll need 1.75″ added to the quarter body back pattern piece. The back dart is 1.25″ wide at the waist line, so one possibility would be to eliminate it, but I don’t want to do that and entirely lose the shaping it provides. Though my waist is wider than typical proportions, my back definitely does have curvature there that a dart allows the fabric to follow. I may narrow it slightly to add some width, but I’ll wait to see how much. Another possibility would be to slash and spread the pattern along something like a princess line hinged at the underarm area, but this is probably more complicated than what I need, and would involve changing the hip, too.
For the sake of simplicity and trying to add girth to the pattern in a way similar to the rectangular body shape I actually have, I’m going to reduce the waistline at the side seam by straightening it, making the same adjustment to the front bodice side seam, because those pieces must match in length and their alignment is crucial to the balance of the final pattern. This adjustment adds 1.25″ width to my quarter body pattern pieces in back and front. The remaining amount I need to add at the waist is .5″ to the quarter body back piece and 1.75″ to the quarter body front piece.
To finish the waist adjustment to the back, I’m going to narrow my back dart width by .5″, leaving me with a .75″ back dart for shaping. To finish the waist adjustment to the front, I’m going to add to the center front by essentially slashing and spreading along the line where the dart was to add space for the additional body volume here.
I want to slash and spread enough to make the waistline 1.75″ larger. (Interestingly, in historical patterns, the center front seam often was curved along this line. To me, this seems like a potentially more accurate two dimensional depiction of the actual body shape in the front of the torso, which is rarely flat, unless you’re very athletic and far more disciplined about food than I.) Another benefit to this pattern adjustment is that in the future, when/if/to whatever extent my body does return to normal, having a center front bodice seam will allow for easy repeat alterations, so my maternity wear isn’t necessarily going to be relegated to the back of the closet for the rest of time, but can shrink back down with me as needed.
Next, I want to look at the high hip. The industry standard for this measurement is approximately 4″ below the waistline, with the full hip approximately 8″ below the waist, though of course this varies from person to person and between different figure types. I want to compare the high hip of the sloper (36″, .5″ of which is ease) to my high hip body measurement (39″), remembering to add .5″ of ease to my body measurement. I know from previous pattern work and from my belly bump that the entirety of this discrepancy is in the front of the pattern.
39.5″ actual body and ease – 36″ sloper measurement = 3.5″ adjustment needed to full front bodice at the high hip.
This will be 1.75″ needed in the quarter body front pattern piece. If I weren’t pregnant, I would probably slash and spread outward at the side seam to add the needed amount, but since the protrusion of my figure is along the center line, I’m going to add it to the center instead. Since I already slashed and spread at the waist to angle the sloper pattern outward and didn’t yet adjust the hip area, I can just measure this amount and alter the center front curvature to add or reduce as needed here. The amount that was already added at the hip by my previous waist adjustments works just fine here.
Then I want to look at the low hip measurement, which is approximately 8″ below the waist, give or take based on height and figure type. In my case, and in the case of any full abdomen to some extent, since the belly bump expands both vertically and horizontally, it will be a bit lower than this, especially in the center front. I’ll be adding extra length to the bottom center front to cover everything. The sloper measures 39.5″ here, with .5″ of that being ease. My body measurement is 41″ here. So I’ll add ease to the body measurement and then calculate to find my needed adjustment:
41.5″ actual body and ease – 39.5″ sloper measurement = 2″ adjustment needed to full front bodice.
So I only need to add 1″ horizontally to the quarter body front pattern piece at the low hip. My previous waist slash and spread adjustment angled the low hip line outward more than this, so I’m going to curve that line back in towards the original center front line a bit. I’m also going to add length here, too. My sloper measures vertically about 9.75″ from waistline to low hip, but my current body measurement is 12.75″ here. I’m going to add about 3″ vertically to cover this.
And that’s it for the major adjustments for the pregnancy belly. I’ll have to add more to the center front as I continue to expand, but the principle is the same. This is by no means the definitive way or the only way to do this in the flat pattern. Most patterns I’ve seen for maternity tend to add extra room/ease at the side seams, which works too, but in a much more drapey way that feels a bit too much like a shower curtain to me. The shape here hugs the curve, much like the cup of a bra pattern curves to encase the shape, rather than just draping over it. The downside of a center front curve like this, though, is that if the curve is bigger than the actual body shape, there will be sagging and wrinkling like a sagging bra cup. But that center seam allows a lot of adjusting as needed to happen during fitting, and changes made there are more independent of the rest of the garment than altering at the side seam might be.
I hope this was helpful, and I hope that my hormone addled brain didn’t make any blatantly obvious, embarrassing simple math errors. 🙂 There are some other adjustments I do to my own sloper for a forward shoulder and broad back that I’ll probably cover in a different post soon. Happy Friday!