A biosensing wearable that tracks and visualizes natural pH shifts during menstruation.
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roles
Product Designer
User Experience Designer
User Interface Designer
User Researcher
industry
Femtech
timeframe
Oct–Dec 2024
skills
Prototyping
Material Fabrication
Interface Design
Research
the challenge
Many women lack accessible, intuitive tools to track and understand their menstrual health
After conducting interviews with college-aged women, we quickly learned that while tracking menstrual cycles was important, there was a gap in existing menstrual products. Smart underwear, smart menstrual cups, and digital tracking apps on the market were advanced and intuitive, but lacked personalization and tangible factors that interviewees desired.
the outcome
We designed a sustainable, biosensing wearable for personalized data tracking
pHeminine takes a hybrid approach by combining physical and digital modalities to provide users with an intuitive analysis as well as a sustainable alternative to disposable, wasteful products. We envision a panty liner that empowers women to understand their body’s natural rhythms through the visual tracking of pH color changes from cervical fluid. Our panty liner is made with 100% cotton fabric and thread dyed with butterfly pea flower and embroidered into a moon cycle-shaped patch. The companion app has a scanning feature to allow users to digitally catalogue their pH trends and learn from AI-powered insights based on ongoing tracking data.
dive deeper
interviews & personas
How do menstruators track and understand their cycle?
We conducted three interviews with college-aged women (20–22) to ask about their strategies, knowledge, and concerns surrounding tracking menstrual cycles. Our findings revealed that menstruators want simple, non-intrusive tools that help them understand their bodies on their own terms without feelings of shame, clinical coldness, and without overwhelming effort.
From our user insights, we created three detailed personas to guide our product requirements and design. Conversations with users uncovered a clear awareness gap, especially around vaginal discharge, which meant these women, and perhaps other women in their life were lacking body literacy when it came to discharge-related menstrual health knowledge.
competitive analysis
What products already exist that help menstruators better understand their cycle?
Research was done on existing companies in the menstrual health space to conduct a competitive analysis to understand gaps in the market and where we could begin to carve a niche for our product. Products like ALMA Smart Underwear, FLO Living, LOON Cup, and Kegg Fertility Tracker are advanced, well-funded projects targeting a similar problem space to the one we defined for ourselves. However, while many of our key features overlapped with some of these products, what they lacked was a focus on biomaterials, sustainability, and insights on discharge.
biosensing discovery
The natural pH indicating properties of butterfly pea powder informed our product direction
In the early stages of project brainstorming, we discovered that pH fluctuation was an overlooked metric when it came to menstrual tracking and analysis. Early research revealed that fluctuations in vaginal pH during the menstrual cycle can indicate normal changes or signal potential health concerns. The biomaterial reactivity of our product results from a natural material known as butterfly pea powder, a natural bioindicator that changes hue depending on the acidity of what it comes into contact with. We initially explored two natural materials: red cabbage dye and butterfly pea powder, but found that the butterfly pea powder yielded a more reliable and legible swatch of colors.
With the pH-reactive properties of butterfly pea dye, users track pH fluctuations across the four stages of menstruation (menstruation, follicular, ovulation, and luteal) to create a personalized, digital map of their hormonal and physiological changes. This mapping provides actionable insights into both regular symptoms—such as acne or mood changes—and irregular indicators, like infection or imbalance, fostering a proactive approach to health.
material exploration
We experimented with paints, plastics, and embroidery to explore material options
From biopaints to bioplastics, we created a variety of bio materials in a wet lab to ideate our product and explore a wearable that was effective and comfortable. In addition to the method of fabrication, we also tested the environments of the material, such as cotton, silk, and polyester to determine comfort and sustainability. We ended up choosing embroidery on cotton as our most effective combination and proceeded to develop a prototype.
One of the most difficult challenges to overcome was the unpredictable nature of the natural materials, including the butterfly pea powder paint and bioplastics. While we envisioned forms for us to create and test, fabrication rarely went as planned, and we found ourselves surprised every time we entered the wet lab. We overcame this by continuously prototyping and making, pushing our idea forward and see what worked and what didn't.
final prototype
A pH sensing patch embedded into a comfortable, sustainable, reusable pantyliner
Our final prototype combines our research on butterfly pea powder with our material exploration to create a sustainable pantyliner with biosensing capabilities that can be washed and reused. Hovering over the image will showcase the visual reactivity the thread has when it comes into contact with acidic or basic solutions.
We chose embroidery for its consistency, reliability, and assumed comfort factor as a material. The material yielded the best results by far when it came to both fabrication and testing, not to mention that it could be more easily implemented into a cloth wearable.
digital pairing
Pairing the physical product with a digital one would allow for the most insight and data optimization
Along with the physical prototype, the product features a companion app that assists with long-term tracking and cataloguing patch data.
1: Scan Patch allows users to digitize their data by simply using their smartphone's camera and aligning the patch with the shape outlines on the screen.
2: My Patch tracks scanned patches daily and provides an ongoing catalogue patch history. Privacy is a top priority with the product, with scans and data being easily hideable if users are uncomfortable with their data being seen by others.
optional ai tracking
Long-term tracking provides visuals of menstrual cycle trends and predictive insights using AI
Scanning patch data consistently allows the user to see and understand fluctuations in their menstrual cycle over time and keep an ongoing, learning log to refer to.
3. Current Status gives a brief, simple overview showing the user if their daily pH range is in a "normal" range for their scale, removing guesswork and delivering concrete insight immediately.
4. Recent pH Trends visualize daily fluctuation in pH levels over the last 7 days to provide a weekly snapshot, which allows the user to infer if their cycle is occurring according to schedule or irregular.
5. Today's Insights gives a prediction on which phase of the menstrual cycle the user is in for clear understanding and informed menstrual wellbeing.
6. & 7. pH Trends take advantage of long-term tracking to provide the user with sustained data visualization of pH trends over months and years so the user can better understand their vaginal health.
thinking ahead
If I had more time I would...
- Research safety standards and evaluate the safety of our product and the materials we used to create it
- Conduct more user research on older women (post menopause) to understand the frustrations, needs, and preferences of individuals in that demographic
- More in-depth competitive analysis of products in the menstrual health technology space to carve a deeper niche for pHeminine.
- Test the patch prototype more thoroughly and explore additional material options.
how ai assisted
ChatGPT helped us visualize our pH spectrum before creating it
We utilized ChatGPT to help us understand what the pH color spectrum would look like for butterfly pea powder in parallel with the fluctuating pH levels during the menstrual cycle. While not completely accurate, the AI results helped us begin to imagine what our eventual wet lab spectrum would look like, giving us confidence and clarity moving forward.
I used Lovable to generate a quick, skeletal framework outlining basic UI elements and navigation features from which I picked and chose the ones I liked the best and recreated them in Figma using my own assets.
pwtloughlin@gmail.com
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