The Period Pad 3.0 - Sustainable, Menstrual Protection with Smart Detection

Consent was given by participants.

Transcript-

More absorption.

Safety.

Accessibility.

cost.

Comfort.

That's how basically all my interviews went.

So my name is Vidya,

to finally solve these challenges that menstrual pads produce.

A large issue is absorption. Regular pads only absorb 10 millilitres,

while mine absorbs 40 milliliters, which is nearly four times as more.

This is thanks to the sponge made out of invasive plants.

Another concern was safety.

This creation is one of the first to detect some illnesses

that have never been detected before, and it also includes a timer.

Next was accessibility,

where I made disability-friendly packaging and made it affordable.

Next was comfort.

High-pressure areas were thinned out, and the pad was made boxy.

to conform to the body.

Finally, my pad is biodegradable

and can be converted into compost to grow plants like these.

Problem:

Period pads are used by almost 3 billion people, yet their design has barely changed in decades. Most disposable pads contain plastic, take 500–800 years to decompose, and contribute heavily to environmental waste (Figures 1 and 2). More importantly, they offer little support for health or safety.

This becomes more serious when looking at health risks. Studies show that people can be up to 13× more likely to develop infections when they are menstruating. This increases the risk of infections such as Bacterial Vaginosis and yeast infections, and in more severe cases, Toxic Shock Syndrome (TSS) (Figure 3), and Clostridium sordellii, which can be lethal if not detected early. It's estimated that millions of lives are lost each year due to menstrual-related causes.

However, current pads:

Do not detect infections

Do not alert users when to change them

Often have poor fit and leakage issues

Are difficult to use for some individuals with disabilities

Create long-term environmental harm

To better understand these issues, I conducted two years of user research, interviewing 130 participants (ages 15–54), including 30 individuals with physical disabilities.

Key concerns included:

Biodegradibilty

Poor absorbency and comfort

Health monitoring

Affordability (Figure 4)

Limited accessibility

Research Question

How can a menstrual pad be redesigned to improve safety and user experience?

My solution:

I redesigned the pad as a multi-functional system that:

Improves safety → detects infections and signals wear time

Improves performance → better absorbency and flow

Improves accessibility → easier, independent use and affordable

Improves sustainability → biodegradable materials

Material development-

Sponge: I replaced conventional materials with invasive plant fibres such as Japanese knotweed and invasive river reeds. These plants were blended and treated(Figure 5) to improve flexibility and absorbency.

Baking soda treatment: broke down lignin, increasing softness

Tapioca starch binder: provided structural integrity

Citric acid crosslinking: improved bonding between fibres

Packaging: developed using invasive seaweed and made in the same way as the sponge.

Absorbency and comfort-

To replicate real conditions, I developed a blood-like solution using a starch-thickened liquid and agar to simulate clots.

Additionally, I used a virtual model to simulate fluid movement. While doing real-life pressure testing (figure 8) and plotting it in the software.

Key design features included:

Plant-inspired channels: guide flow and reduce turbulence

Cotton mesh layer: prevents blood clot blockage, as blood can seep through

Variable thickness design: to improve body conformity

Infection detection-

The pad incorporates multiple colorimetric detection systems (Figure 7), each targeting a specific biological marker:

Bacterial Vaginosis → detection of unique amines

Yeast infection → detection of β-glucans

Toxic Shock Syndrome → cell wall and toxin targeting reactions

Clostridium sordellii → toxin-based detection

Broad detection → pH-based detection, from polyphenols of the butterfly pea flower

Each reaction was optimized to detect clinically relevant concentrations (~10⁶ cells/mL).

Timer-

A modified iodine clock reaction was used to create a delayed response system of 7-8 hours, by adjusting reactant concentrations,

Once triggered, it produces:

A visual color change

A tactile expansion through gas formation, using baking soda.

Accessibility-

Multiple ways of opening the pad were implemented. It was tested with a glove that inhibited fine joint movement (Figure 9) and used on my non-dominant hand; the glove was also greased with oil. The goal was to open it in under 30 seconds, averaging it over 5 times.

Method #1: Finger loops

Method #2 String

Absorbency & Comfort-

The pad absorbs up to 4x more than conventional pads (40ml).

Channels: distribute flow efficiently, reducing pooling, leaks and friction

Mesh layer: prevents clots from blocking channels.

Body-conforming shape: with a thinner center and flexible slits. (Figure 15)

Infection detection-

The pad visually signals the presence of infections via color changes:

Bacterial Vaginosis (Gardnerella vaginalis) → purple

Yeast infection (Candida albicans) → yellow

Toxic Shock Syndrome (Staphylococcus aureus) → blue and purple (2 lines) (figure 12)

Clostridium sordellii → green (figure 11)

pH detection → Blue when basic, magenta when neutral and pink when acidic. (3-5)

Science behind it:

Each reaction takes advantage of unique aspects of that bacteria or fungus, and uses chemicals to react with them, and then visualizes the reaction. Polyphenols from Butterfly pea flower react with the surrounding pH and emit colour.

Timer Function-

Timer: Uses a modified iodine clock reaction that activates after 7–8 hours.

Produces colour change (visual) and bubbling (tactile) alerts.

Science behind it: This reaction contains two solutions battling to overtake each other, a vitamin C solution and an iodine solution. Iodine always overtakes vitamin C; by changing the concentrations, the "battle" can last longer. Using the transition of iodine atoms into ions to my advantage, I placed baking soda, which reacts only with the ions, producing CO2 gas.

Accessibility-

finger loops, straps, and multi-opening packaging (figure 13): for one-handed use were used.

It took an average of 13.5 seconds to open, whereas the conventional pads took nearly 20 times longer.

20 cents, which is 40% cheaper then current options.

Biodegradability & Composting-

Fully biodegradable pad composts in 30 days indoors, ~50 days outdoors.

Activated charcoal was added to reduce odour without harming beneficial insects.

Tested compost supported plant growth comparable to commercial compost (French breakfast radishes). (Figure 14)

Science behind it: Invasive plants provide natural fibres that break down quickly, while additives like charcoal control odour and microbial growth.

Packaging-

Made from seaweed fibres, naturally waterproof and fully biodegradable.

Shelf-life tests:

Dark, dry conditions → pad performs perfectly after 1 year

Direct sunlight → dyes fade, pad stiffens

Moist conditions → risk of mould

Last year's pad-

held 30ml, which is 25% than the current iteration.

Original channels created friction = Less absorption.

Only detected two infections, Bacterial Vaginosis and Yeast infection. While not sensitive enough to detect early development.

Boxy shape allows for optimized fluid movement during rapid motion

pH detection offers too wide a scope to detect small, detrimental changes. (2-12)

My pad is more than just a product; it’s a solution to problems millions of people face every day.

Health & Safety

Colormetric detection: detects common and lethal infections like yeast infections, Bacterial Vaginosis, Toxic Shock Syndrome, and Clostridium sordellii before symptoms worsen.

7–8 hour timer: reduces bacterial growth, preventing health risks associated with wearing pads too long.

pH monitoring: adds another layer of safety, alerting users to abnormal changes. (Figure 17)

Impact: Monitering of menstrual health without invasive tests, making periods safer for everyone. This pad also contains the first way to ever diagnose Toxic shock syndrome and Clostridium sordellii. Potentially saving thousands of misdiagnosed lives.

Comfort & Accessibility

Body-conforming shape: improved absorbency and channel (Figure 19) design reduce leaks and discomfort.

Inclusive design: allows people with physical disabilities to use loops, straps, and easy-open packaging to open pads independently

Impact: All implementations used have been created for the first time, and haven't been done before. This allows individuals to move on all axes of movement with ease.

Sustainability

Entire pad is fully biodegradable, composting in 30–50 days.

Made from invasive local plants, reducing reliance on cotton and plastic.

Compost tests show it supports plant growth, making menstrual waste environmentally beneficial. (graph)

Impact: Reduces billions of pads in landfills and turns waste into compost, while safely converting blood into compost. As menstrual blood has too many pathogens to be a beneficial compost alone.

Future Directions-

Digital app integration: for visually impaired users

Finalizing production method: for broader access

App development-

I have been working on an interactive app for people with disabilities and users who have positive results; this scans the period pad and notifies the user about which illnesses are positive and how to dispose of the pad. One of the other functions that I'm working on is a "gynecologist finder", so users can find a health professional and get care immediately.

How it should work:

When a user opens the app, they should be able to put in their personal information, like their city and age. Then scan their pad and get crucial feedback.

I first love to thank my interviewees, as their feedback was the basis for my project and extremely helpful. It allowed me to find the crucial gaps in this industry and fix them.

I'd also love to thank my science teachers for allowing me to access the school laboratory for my project.

I'd also love to thank my family, especially my sister, as she went through the effort of proofreading my project and helped teach me about app development.

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