It is so important especially when designing new period products and garments that we don’t repeat the mistakes of the past. We need to move away from potentially harmful, unnecessary and fossil fuel derived materials and anti-microbial and anti-odour additives. Yes we do need to divest our period products! 

Cheap should not mean shoddy and reinforcing the age old and tired taboos around menstrual odour is not progressive but regressive. In the absence of proper regulations we are at the mercy of the period product industry in terms of safety, sustainability and transparency when it comes to new and innovative products. 

There are so many producers who go to extraordinary lengths to ensure their product’s are the best they can be and are safe for us humans and our environment. Bold intimates have compiled a thoughtful guide to take period entrepreneurs through concept to finish product.  

In this guide, Nicola Hopkins, Director and Technical Designer at Bold Intimates Ltd a product development studio and consultancy for Intimate Apparel brand, shares insights into their work and outlines some key product development considerations. The hope is that this guide will inspire as well as offer direction to any brands looking to produce or add period apparel to their collection. 


Knowing that the human body is inherently full of wisdom, like nature a bleeding body has seasons, a cycle and a deep intuitive knowing. I am extremely passionate about standing for cyclical living as a guide for creating a thriving future for our planet. 

Reusable fabric period pads and pants can be developed to work in sync with the human body and the environment, remaining in circulation for as long as possible.

With a broad range of period care products including apparel coming to market in recent years and many more in development I believe in the power of communication and collaboration at this time of great opportunity to carve out together new healthy, circular product supply chains which benefit the whole.  


Designing and producing reusable period apparel such as pants and pads.



As you begin your product build journey, you’ll have many ideas about what the product needs to look like and perform like. It’s advisable to work with an experienced apparel designer who will be able to translate your vision into workable and viable CAD designs and a Technical Pack/specification that you can use to communicate with suppliers and manufactures overseas.

The desired aesthetic will depend greatly on your target consumer demographic. It’s a good idea to consider what silhouettes are the most popular amongst your target customer, along with colours and fabrics so you can imagine how your product will work seamlessly with clothing the customer already has. Waist height and leg lines are key considerations here.

Some key questions to consider: What do you imagine your customer will want to do whilst wearing this product? How may they feel physically and emotionally at this time of the month? This may impact your style lines as well as construction and fabric choices.

Consider how the product will be worn, for how long and at what times of day. It is common to develop a range of period apparel for different levels of flow (/absorbency) or for day and night wearing. You can have anything from a panty liner to support with spotting to a super absorbent short that can hold up to 10 tampons worth of blood.

When you get down to the performance level, it’s important to be clear on what deliverables are the most important for your brand and ensure these are included at every stage of the product build. For period apparel key performance indicators often include softness, breathability/air flow, moisture wicking, absorbency and temperature regulation to keep the wearer feeling comfortable, fresh and dry.

Designing and developing new products is exciting, however remember the goal here is slow, conscious, meaningful creation and consumption, so keep a product line small and tight and only look to produce new items based on customer feedback and demand.


Photography by Matthew Pull


When selecting materials for your period apparel there are many elements to consider and I do not recommend this part of the product development to be taken lightly or rushed. Material sourcing is best actioned directly alongside design and supply chain set up as these three fundamentals will need to work in alignment. 

To be truly healthy and sustainable it is important to consider the impact of a material on both the environment (where it originates, where it is produced and where it ends up), the people in the supply chain and on the body of the wearer in garment form and as such an as natural as possible approach is recommended.

Our current fashion and period care landscape has gotten very comfortable and established at using synthetic fibres in performance wear to keep us dry and comfortable. Polyester and nylon fabrics are very good at moving liquid away from the body. 

We know that these synthetic textiles release thousands of micro-plastics into our water systems and marine habitats when washed as well as not being kind to our intimate areas. Period apparel provides us with a unique opportunity to explore a return to natural fibres and properties which may be just as effective as synthetics at keeping us dry and comfortable. You can read more about the plastic problem in the fashion industry on the Bold Intimates website here.

The natural fibre route is abundant to explore with both centuries old established materials and new developments. Look for familiar fibres such as certified organic cotton, hemp, wool, bamboo and perhaps some new innovations including lyocell, seaweed and pineapple! Bio based fibres such as these tend to have fantastic absorbency, moisture wicking, breathability and natural ability to resist odour as well as being more easily returned to nature at the end of their life.

One of the main challenges we face currently as Intimate apparel designers is the use of elastane. Intimate garments need to be supportive and fit to very contoured areas of the body, they need to stay in place whilst also allowing the body to move freely. They also need to retain their shape over time and multiple wears and washes. Materials with elastane stretch and allow us to achieve all of these things. However, for ultimate vulva health, and biodegradation at end of life we need to consider removing or replacing elastane. In gusset layers and certainly in pads, elastane is not needed. There are some incredible eco-friendly stretch fibres being innovated currently, such as  Creora® by Hyosung, a bio based spandex, certified by Standard Global Services (SGS).

To inform your fabric selection, a level of scientific understanding about how liquid reacts to different fibres and constructions is required. Your product will likely have multiple gusset layers, each doing a different job. Any fabric/layer against the body will need to be soft, stay dry and adept at moving moisture. A second layer will need to have high absorbency to hold the liquid for a length of time. There will also need to be a liquid repellent barrier to stop it moving out through the garment too quickly. Trims and methods of construction are also an important consideration when it comes to dealing with liquid flow. 

Many brands are still using a human-made plastic membrane for the waterproofing layer, such as a PUL (polyurethane laminated polyester), however not all brands use this and it is possible to create period apparel without. There is exciting research and exploration happening on how to create waterproof seals organically and mimicking nature. The inspirational brand Sumo has created nappies derived from seaweed fibres and using a waterproofing technology enabled by a partnership with Swiss textile company Schoeller, which does not affect biodegradability or recyclability.

We can also be mindful of how we can create circular efficiencies within the product build and production choices by minimising and utilising waste. Talk to your suppliers to see what opportunities there are for collaboration. It may be possible to group together with other brands to meet an MOQ (minimum order quantity) or use organic cotton scraps left over from t-shirt production for your period pads. How can you utilise what is already in existence without producing virgin fibres or making large orders that you won’t use?

“On average, 35% of all materials in the supply chain end up as waste before a garment or product reaches the consumer. This could be cutting waste, un-useable stock due to last-minute design changes, spoilage in transport, or excess stock that is not sold on the retail market and, at times, is incinerated by brands.” Pulse report 2017

One example of this approach can be seen by the underwear brand One Essentials, who prioritise reducing virgin cotton, by blending it with recycled cotton thus keeping the yarn in circulation for longer and reducing their energy and water usage as well as CO2 emissions.

For all materials, look for accreditations which show the supplier is following the highest environmental and social regulations. Major ones to look out for include Global Organic Textile Standard (GOTS), GRS, Cradle to Cradle and Bluesign®.



Any chemicals used in producing your product are likely to end up in the environment as well as being in close contact with the humans working in the supply chain and of course directly against the skin of the wearer and one of the most sensitive and absorbent areas of the body. Mucous membranes in the vulva rapidly absorb chemicals without metabolizing them, thus potentially exposing us to higher levels of harmful chemicals in underwear, compared to garments worn on other parts of the body. Educate yourself around EDC’s (Endocrine Disrupting Chemicals) and where these have the potential to show up in the supply chain for menstrual products.

Consider and question any potential chemical treatments used in the process of growing your fibre crop, (such as pesticides), creating the fibre, manufacturing the fabric and final garment, including dyes, bleaches, fixes, softeners, chemical washes and waterproof repellent (DWR) treatments.

Recent research has found potentially harmful ‘forever chemicals’ or PFAS (Per and polyfluoroalkyl substances) in period underwear products, which could potentially end up in our bloodstream for years, not to mention will be released into the environment when the product enters a landfill. The most commonly studied PFAS have been linked to hormone and immune disruption, decreased fertility and increased risk of certain cancers.

Textile dying traditionally requires a high level of chemical input as well as large volumes of water and energy. Amongst the most harmful are Azo dyes, which can contain hazardous substances such as heavy metals, aromatic amines, and formaldehyde-based compounds.

Natural dyes derived from renewable resources shine as an eco-friendly choice. They are biodegradable and non-toxic, coming from nature and return to nature with minimal ecological footprint. However, they are not without their complexities around colour consistency and fastness and they still use a large amount of water and can impact agriculture.

Reactive/solution dyes are synthetic however are currently considered one of the more environmentally friendly ways to colour fabrics as the dying takes place at the yarn level and uses minimal water and emits minimal carbon. They also achieve a strong level of colour and fastness than natural dues, which often can mean the garment will last longer. You can read more around the status and challenges of creating colour and sustainability in the Intimate Apparel industry on the Bold Intimates website here.

Oeko-tex standard 100 is a globally recognised test for harmful substances, covering numerous regulated and non-regulated substances which may be harmful to human health. Every part of the product can be tested from the thread through to the finished complete garment. The Oeko-tex criteria is updated at least once a year, however, be aware that it doesn’t cover all known PFAS, such as fluorine and is by no means exhaustive.

*Wen notes that there is currently no legal limit on the amount of silver (used to control odour) allowed in textiles and textile standard Oekotex doesn’t currently contain any requirements around silver content.


 The materials you choose will need to be explored directly alongside manufacturers and consideration of the whole supply chain. Whatever route you decide to go it is important that you fully understand the supply chain and how that raw material has been grown, spun and knitted.

You will need to find a garment factory who is able to make your level of product quality at the price point you need, for the quantity you need. Garment factories, as well as fabric suppliers will have MOQ (minimum order quantities) and MCQ (minimum colour quantities) and lead times that you will need to follow in order to do business with them so it’s important to be clear on your business model, target cost and retail prices before starting to make prototypes.

It’s also important to consider logistics of the factory to your raw materials and point of sale. It is advisable to keep your supply chain as local as possible thus limiting carbon footprint from flying fabrics or products around the world unnecessarily. You will often find that a good manufacturer will be able to offer fibres and fabrics that are produced in their region and it may be something you had not considered. There is potential for exciting innovation by building these kinds of supply chain relationships.

Looking for manufacturer compliance accreditations such as WRAP, Sedex and BSCI is very important and reassuring that their set up is regulated for social and environmental global standards. However, do not underestimate the power of establishing mutually caring relationships with your suppliers over time and creating healthy systems together.



Once you have your materials and supply chain in place and your design drawn up with an accompanying Technical specification you are ready to proceed to prototyping. Often prototypes are made by your garment factory. If the product is more complicated (E.g. A new fibre development or scientific theory you wish to apply) you may want to find a local machinist who can create initial concept prototypes for you. This will allow you to test materials and construction methods and refine your technical specification.

Once the factory start working on samples, it is usual to work through several rounds of pattern cutting and samples which will allow you to check the sizing, fit, construction, performance and quality. For samples it’s important all materials used are bulk representative (if not actual bulk material you intend to use). Make sure to check this with your material supplier as sometimes sampling may not be finished in the same way it is for production which may be fine for checking the fit but will impact the performance during wearing.

After each sample round is fitted, inspected and tested you will need to give comments back to the factory/machinist for the next round. It is advisable to work with an experience IA technician for this part to ensure a smooth translation of critical requirements which will be sure to make your sampling process as efficient as possible. Whilst physical sampling and testing is extremely important to ensure the efficacy and longevity of your product, unnecessary rounds of sampling are one of the biggest culprits of waste in the fashion industry.


Photography by Matthew Pull



Apparel sizing varies between countries and brands and we also use a range of ways to communicate it, including numerical, alpha sizing, as well as single or double sizing or one size fits all sizing! Whilst you may be able to take direction from existing brands on the market, it’s important to really understand your customer and the unique product you are creating. 

Fittings are usually carried out by a technician with a professional fit model. In the fitting, the technician will analyse the sample on the model for sizing, style lines, fit, comfort and the wearers overall experience to make improvements for the next sample round. They will consider pattern amendments that could be made to improve the fit and performance as well as the impact of the materials, trims and construction.

For apparel, where there are multiple sizes, once your base size is approved the pattern will then need to be graded and other sizes sampled and fitted to ensure the fit, styling, materials and performance are suitable for the whole size range.



With Period apparel the performance of the garment needs to be tested extensively. This can be done by actioning wearer trials with professional intimate apparel models or indeed anyone that you know who is willing to test the product and give honest and clear feedback. It’s a good idea to keep well documented records so that all data can be compiled and analysed as a whole.

You may also look at liquid testing your product off the body to capture how much liquid it can absorb over a certain period of time and to determine the absorbency level. Many brands quantify and communicate this in ‘number of tampons worth’.

Once you have selected your materials and confirmed they are suitable in garment form it is common practice to gather your bulk performance tests both from material suppliers and independent test houses. These tests capture physical performance criteria such as pilling, tearing, bursting strength, dimensional stability and colour fastness to ensure the fabrics are fit for the commercial purpose you intend for them.

Finally, when you are happy with the product performance you will be in a position to order your bulk materials and book your production slot with the factory.



Consider the customers’ expectations around washing period apparel, you may need to educate and encourage them to take care of their products to make them last as long as possible and to be as healthy and useful as possible, with minimal use of water and energy.

We recommend rinsing products under cool running water and then machine wash at a low temperature as part of your regular wash and using a plant-based detergent. If your product contains plastics, a lingerie bag designed to catch micro plastics will also help to reduce the amount ending up in our waterways. Hang or flat air dry instead of tumble drying to make the fabric last longer as well as to reduce energy use.


“In Europe, on average, up to 60 percent of the greenhouse gas emissions from laundry come from heating the water in our washing machines—more than packaging or ingredients. Dialing down the temperature by just a few degrees can dramatically reduce energy waste.” – National Geographic


By ensuring care and consideration at each stage of product development, we can create products that our customers love, will wear for a long time and lovingly take care of.

However, a time will come when the garment can no longer be worn. When selecting materials and methods of construction, I would encourage any brand to consider a viable end of life solution for each garment. Can any parts be recycled? Will it bio-degrade? Can you offer take back products for industrial recycling or composting? At present the fashion industry lacks infrastructure and technology to recycle large volumes of discarded clothes, particularly when the fibres are mixed and difficult to separate. Consider what you can do to mitigate this impact and design recycling into your product from the beginning.

A brilliant example of life cycle consideration can be seen by BB pads, their reusable period pads are designed to last between 3-5 years. When they do eventually reach the end of their lives, they are home-compostable as even the thread is non-synthetic, the dyes are plant-based and the buttons are made from coconut shell. 

“Today, only 20% of textiles are collected globally. To achieve a circular fashion system it is essential that we capture the valuable resources currently being lost. Setting up a garment collection scheme is a pragmatic step in the right direction.” Jonas Eder- Hansen, COO at Global Fashion Agenda.


It’s important to note that this blog is by no means exhaustive. The knowledge and data around sustainable, healthy period apparel development is extensive and constantly being advanced.

Be sure to do your own research and be accountable for each step of your product build and supply chain. Being transparent, authentic to your unique brand mission and willing to collaborate with aligned, regulated organisations at this critical stage of systemic development will make the world of difference to both your customers and the planet!


Environmenstrual Coalition member, Bold Intimates is a product development studio and consultancy for Intimate Apparel brands, offering technical design, responsible sourcing and supply chain set up, pattern cutting, grading, prototyping, fitting and garment testing services for pioneering projects and brands who want to have the important conversations and build meaningful products with integrity.

 The studio is born from a deep desire to bring human connection back into how we produce intimate garments, trusting that by being connected to ourselves and others we are in turn connected to mother nature and our planet.


Guest blog by: About Nicola Hopkins, Director and Technical Designer at Bold Intimates Ltd and Founder of the Intimate Apparel Technical Collective.

(Banner photo credit: BB pads by Cat Arwel Photography)

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