Sunday 26 January 2020

Abena Abri-Form M4 Adult Diaper Review (Original X-Plus)

*For information on how I do reviews see Diaper Test Methodology


The Abri-Form M4 (Original X-Plus) is a highly absorbent plastic-backed adult diaper with thick, extensive padding coverage. In North America it's regarded as one of the premium European diapers and was one of the earliest such diapers to enter this market. In recent years the market for high end diapers has become more competitive and it is now regarded as one among many in this space. Even so, the M4 can still be found at a competitive price-point in online shops. This is a diaper for heavy wetters and it was not designed with discretion in mind; it should provide particularly good protection for bedwetting or for wear during days of low activity. It does have its shortcomings and during the course of this review I had issues with the refastenable tapes, surface dampness and padding deterioration. In spite of that I found this diaper is quite comfortable and would recommend it wherever it can be found for a good price, but it's not worth the premium that some shops charge for it. It should also be noted that there is an almost identical cloth-backed version of this called Abri-Form Air Plus, which often comes in a dark blue rather than green package.

Key Features:
  • Refastenable tapes
  • Plastic-backing
  • Standing inner leak guards
  • Thick absorbent padding

  • Thick padding extends well up the back of the diaper
  • Soft padding, backing and leg gathers
  • High rate of overall absorption

  • Padding becomes damp to the touch when wet
  • Refastenable tapes can become stuck to the backsheet
  • Expensive unit price

Product Details

For the purpose of this post I will be reviewing and referring to the medium (M4) Abri-Form diaper. However, other available sizes are listed below.


Brand: Abri-Form
Manufacturer: Abena A/S
Origin: Denmark
Units Per Bag: 14
Cost Per Unit: $$$
Dimensions (L x W x H): 38 cm (15”) x 18 cm (7.1”) x 26 cm (10.2”)
Weight: 2.63 kg (5.8 lbs)
Available Sizes: M, L
Advertised Absorbency: X-Plus

1.1 Abri-Form M4 Packaging


Backsheet: Plastic (Poly)
Wetness Indicator: Yes (two solid yellow lines down the middle, turn blue when wet)
Standing Inner Leak Guards: Yes
Leg Gathers: Yes
Product Style: Tab-Style Brief
Refastenable Tabs: Yes
Number of Tapes: 2
Repositionable Tabs: No
Outer Color: White (with blue lines next to the wetness indicator)
Inner Color: White
Front Waistband: No
Rear Waistband: No
Folded Thickness: 2.8 cm (1.1”)
Folded Length: 26.5 cm (10.4”)
Dry Weight: 183 g (6.5 oz)
Fragrance: None
Diaper Dimensions (L x fW x mW x bW):
80 cm (31.5") x 62.2 cm (24.5") x 28 cm (11") x 61 cm (24")
Wing Shape (Front, Rear): Rectangular, Rectangular
Padding Dimensions (L x fW x mW x bW):
69 cm (27.2") x 30 cm (11.8") x 17 cm (6.7") x 33 cm (13")
Padding Wing Dimensions (fPW x fPH x bPW x bPH):
6.5 cm (2.6") x 16 cm (6.3") x 8 cm (3.2") x 20 cm (7.9") (height averaged)
Padding Wing Shape (Front, Rear): Semicircle, Semicircle
Total Padding Area: 1701 cm2 (264 in2)
Tape Spacing (t1 x t2): 2 cm (0.8”) x 15 cm (5.9")
Tape (W x L): 3cm (1.18) x 4.5 cm (1.77)

1.2 Abri-Form M4 Diaper

Laboratory Absorbency Tests

Total Absorption Volume (after press out): 1442 ml (50.9 oz)
Total Absorption Volume (before press out): 1617 ml (57 oz)
Time to Absorb Wettings (first to last): (53 s, 49 s, 51 s, 53 s, 57 s, 56 s, 60 s)
Wet Folded Thickness: 5.5 cm (2.17 in)
Used to Total Padding Ratio: 91%
Total Padding to Absorbency Ratio: 1442 ml / 1701 cm2 = 0.85 ml / cm2  (0.19 oz / in2)
Press Out Volume: 175 ml (6.2 oz)

Surface Dampness Rating: 4

The Abri-Form M4 performed very well in terms of absolute absorption but showed signs of surface dampness from the very first wetting. In all subsequent wettings the paper towel test was a failure as moisture bubbled up from the M4 whenever it was pressed. The M4 was relatively slow in its ability to wick moisture, which resulted in temporary pooling and may have contributed to the surface dampness; however, it was also clear that the padding itself was not particularly resilient to leaks under pressure. The M4 has an impressive amount of padding and is unlikely to leak until the 3rd wetting for that reason alone, but I couldn't rate it higher than a 4 for surface dampness based on the paper towel tests.

2.1 Wet vs Dry Diaper After Capacity Test

2.2 Used vs Unused Padding After Capacity Test

"Real World" Absorbency Tests

Posture Tests


Total Absorbed Volume: 1437 ml (50.7 oz)
Total Wettings: 5 (1 standing, 4 sitting)
Leaked After Sitting: No
Used to Total Padding Ratio: 89%
Padding to Absorbency Score: 1437 ml / 1701 cm2 = 0.84 ml / cm2 (0.19 oz / in2)

Standing-Sitting Rating: 9

The Abri-Form M4 performed remarkably well in the standing-sitting test. It had no trouble taking a full void while standing and the initial dampness was barely perceivable. Moreover, there was no sign of leakage upon sitting. While seated, the M4 became progressively more damp on consecutive wettings but failed to leak until the 4th. However, even at the point of leakage only a small amount of moisture leaked out and it felt like it may have been able to take another wetting were it not for its relatively weak wicking ability (hence the unused padding on its backside). The thing that stood out the most during this test was the impressive padding surface area; the padding extends well up both the back and front and the central padding is wide at the crotch. It was quite apparent that this diaper would provide enough protection to avoid leakage from any number of postures. Although it performed very well in terms of absorbance, the surface dampness observed in the laboratory test was also apparent during this test and consequently I couldn't quite rank it a 10.

Lying Down

Total Absorbed Volume: 1217 ml (42.9 oz)
Total Wettings: 4
Used to Total Padding Ratio: 80%
Padding to Absorbency Score: 1217 ml / 1701 cm2 = 0.72 ml / cm2 (0.16 oz / in2)

Lying Down Rating: 8

The Abri-Form M4 is frequently rated among the top diapers for absorption and was easily able to take 3 wettings laying down without leaking. On the first wetting the extensive padding quickly captured the moisture and the diaper felt little different from its dry state. It was clearly slower at absorbing on the second wetting and felt damp for a little under a minute before it has spread through the topsheet. By the third wetting the surface dampness observed in the laboratory test was perceivable, which resulted in the diaper feeling a little less comfortable; by this point the wide padding started to clump in the middle a little as well; yet shear volume of padding again prevented leakage. By the forth wetting much of the padding at the back of the diaper was saturated from previous wettings and the leak guards were quickly overrun, resulting in substantial leakage. Due to its poor wicking ability a large part of the front of the diaper remained dry even as moisture began to leak out the middle and back. Based on this experience I would say the M4 can comfortably take 3 wettings laying down but most likely will always fail on the forth. The diaper deserves at least an 8 for its impressive absorption capacity, but surface dampness and weak wicking have me hesitant to rank it in the 9~10 range.

2.3 Pattern of Used vs Unused Padding Test Stand/Sit (right) / Lying Down (left)

Daily Wear and Bedwetting

The Abri-Form M4 is among the most absorbent adult diapers on the market and lived up to its famed absorbency during testing. It seemed particularly well suited for overnight wear with wide padding at the crotch that extends well up the back. This diaper can be expected to absorb at least 3 wettings laying down, which should be enough for a typical night. In spite of its fairly poor ability to hold back surface dampness the leak guards are very effective and it shouldn't be expected to leak under modest pressure (sitting/laying down). The padding is particularly soft and won't interfere with sleep. The only downside to using this diaper for extended/overnight wear is that the presence of surface moisture can lead to skin irritation. Less relevant to the wearer, but perhaps more to a caregiver, the wetness indicator on the M4 can be slow to respond and will remain yellow for minutes after a wetting before eventually turning blue. Whether this diaper would be a good choice for daytime wear is a harder call. It undoubtedly will be able to handle anything the day will throw at it, in fact I found it was even more absorbent in most daytime circumstances. The main problem you'll find with the diaper is that it's very thick and could be difficult to conceal under most outfits. The size of the diaper also doesn't lend itself to active wear. I believe it could still be effective for a daytime wearer with mobility issues or around-the-house wear, but it's probably not a diaper you'll want to wear for a day in the park under your light summer clothing.

Suitability for Bowel Incontinence: 8

The Abri-Form M4 certainly ranks among the top diapers for potential in managing bowel incontinence. This diaper has some of the widest rear padding on the market and plastic backsheet/inner leak guards. If the fit was a little snugger this would easily rank toward the top, but I do feel it will be a bit more susceptible to the escape of odors than you might otherwise want.

Wear & Tear Tests


The Abri-Form M4 diaper uses a double tape mechanism to fasten with two tapes per side. The tapes can be attached to any part of the backsheet but the blue bottom tapes cannot be reattached if mistakenly placed. If you don't get it right the first time you can re-attach the white tapes over a different part of the backing but that will prevent further fastening. If you get it right the first time the diaper can potentially be unfastened/refastened multiple times; however, in practice I've found when the diaper is fitted snuggly the back of the white outer tapes can become attached to the backsheet and will tear it when removed.

3.1 Abri-Form M4 Fastener

Easy-of-Use Rating: 6

It's not particularly difficult to get a snug fit with the Abri-Form M4 diaper; however, it can be a bit loose at the top as it lacks waistbands. The center lines can assist in positioning up the tapes, but I still found it a little challenging to get them evenly aligned (not that you necessarily need an even alignment for a snug fit). The double-tape mechanism is a plus when it comes to management, but the fact that the refastenable tapes can get stuck to the backsheet over time had me hesitent to give it a higher rating for ease of use. Depending on how the diaper was fastened the tape issue could make it a little challenging to remove.

3.2 Abri-Form M4 Fit


Comfort Rating (dry): 9
Wearing the Abri-Form M4 diaper is a little like wearing a pillow. The padding is thick, soft and extensive, covering much of its surface area, so very little backsheet comes in contact with the skin. The backsheet itself is plastic and also relatively soft. If I had any complaints it would be that the padding at the crotch may be a little too wide; it has a tendency to bunch up. Even so, it doesn't have a substantial impact on the dry diaper comfort. I suspect the M4 could get a bit uncomfortable when warm, but the extensive padding should also lessen any discomfort due to sweating and it's not exactly a diaper you'd wear for exercise.

Comfort Rating (wet): 7
In spite of the surface dampness issues that came up during the laboratory tests, the M4 felt little different from its dry state in terms of comfort after 1~2 wettings. This again was likely due to the extensive padding coverage. Moreover, the M4 was very resistant to clumping when wet. That said, by the 3rd or 4th wetting the surface dampness will become very apparent and the diaper will be substantially less comfortable. For this reason I've given the M4 a compromise score of 7.

3.3 Abri-Form M4 Topsheet and Backsheet


Dry Padding Deterioration Proportion: 8.8% (topsheet), 4.9% (backsheet)
Shake Deterioration Test: 8 shakes to deterioration

Durability Rating (dry): 7
Given the Abri-Form M4 diaper is designed for extended wear I put it through an unrealistically long dry durability test. The test was over 10 hours, but didn't involve much more than sitting and walking short distances. In terms of comfort the diaper did reasonably well, but by the end of the test the padding was clearly starting to break and clump in the center. I believe this to be a result of the padding being a bit too wide at the crotch for daily use, hence the stretching / compressing of sitting/walking started to wear it down. The wetness indicator also seemed to respond to sweat and small amounts of post void dribble. In spite of the relatively high percentage of padding deterioration I still rated it a 7 with respect to dry durability because it can be expected to hold out well in terms of durability in the areas it's best suited for like bedwetting; in these cases the diaper padding likely won't deteriorate as quickly due to less stretching/compression in the crotch area.

Durability Rating (wet): 7
The M4 diaper showed a high degree of resilience during the wet durability shake test, taking a full 8 shakes before the padding began to deteriorate. Moreover, no padding escaped the diaper. However, this was done on a new unworn diaper and you can expect considerably less durability for the M4 when worn. When worn it will suffer the same issues as it does in its dry state with the compression/stretching of the padding around the diaper's crotch leading to deterioration and eventual clumping. I settled on a 7 for M4 wet durability, it's plenty durable for the situations you'd likely use it, but could still use some improvements in this area.

3.4 Abri-Form M4 Dry Test Deterioration

Discretion Tests


Front Rise Above Waistline (Jeans, Sweatpants): 6 cm (2.36"), 6 cm (2.36")
Back Rise Above Waistline (Jeans, Sweatpants): 6 cm (2.36"), 5 cm (1.97")
Side Rise Above Waistline (Jeans, Sweatpants): 3.5 cm (1.38"), 4 cm (1.57")

Profile Discretion Rating: 3

The Abri-Form M4 can hardly be considered a discrete diaper. Under most outfits there will likely be a visible diaper bulge. I'm sure with a careful choice in dress you could hide it, however, your choice of outfits would be limited. It will protrude well above the pant-line so it could be exposed by a slight shift in the shirt. The M4 provides a great level of absorbance, and if you're a very heavy wetter it might be necessary for going out, but I would say it's far better suited for overnight wear.

4.1 Abri-Form M4 Jeans Profile (left) vs Normal Underwear Jeans (right)

4.2 Abri-Form M4 Sweatpants Profile (left) vs Normal Underwear Sweatpants (right)


Noise Rating: 7
In spite of its thickness and plastic backing, the Abri-Form M4 is relatively quiet. If you walk down a quiet hall way it will produce a distinctive crinkling noise, but in most cases where I could see someone wearing this diaper noise won't be an issue. Like most diapers it will be a bit louder when wet but not considerably so. In figure 4.3 you'll see the observed waveform of crinkling produced by the M4 diaper when shifting from sitting to standing multiple times nearby in a very quiet room.

4.3 Abri-Form M4 Sit-Stand Noise Profile

Odor Reduction

Odor Reduction Rating: 5
The Abri-Form M4 doesn't have any perceivable added fragrance, nor does the padding/backsheet emit any. With respect to odor reduction it works well to a point. But, by the 2nd or 3rd wetting it will emit an ammonia odor, perhaps because it doesn't have waistbands/enough topsheet odor protection. For this reason I've rated it a 5 for odor reduction, as it ranks well for overall absorbance but is relatively less effective at retaining odors than other diapers on the market.

Want to give the Abena Abri-Form a try?

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