Women in low-and middle-income countries struggle to maintain good menstrual hygiene. This is in part due to a lack of affordable sanitary products . Poor menstrual hygiene can cause increased vulnerability to urinary and reproductive tract infections, which can lead to infertility and other reproductive organ issues [2, 3]. Moreover, unaffordability of sanitary products restricts active participation of girls in school, contributing to gender inequality. For example, as high as 40% of girls in India are absent from school when menstruating  and in Africa it increases to 66% . If sanitary products could be made affordable in terms of cost and product quality, then it will be possible to significantly increase school attendance, allowing girls to complete their basic education . As widely reported in literature, females staying longer in school is linked to reduced maternal death; improved population health; increased contraceptive uptake; improved child health; increased vaccination rates and decreased HIV infection rates [7, 8].
The traditional ways of managing menstrual bleeding in such countries is the use of old clothes, paper, cotton, wool pieces, and even leaves which have unreliable levels of absorbency. These unreliable absorbents of traditional menstrual hygiene products can keep girls away from attending school. Therefore, provision of superior absorbents and cost-effective menstrual hygiene products can reduce fears of soiling outer garments allowing better school attendance . Further, schools have insufficient private changing areas, poor water/sanitation, and inadequate disposal facilities. This results in disposal of menstrual hygiene products in deserted areas or in latrines to avoid embarrassment, causing environmental pollution . One of the ways to address this matter is the use of fabric pads and/or disposable pads manufactured from biodegradable materials such as bamboo fibres, hyacinth and banana fibres. Having said that, commercial biodegradable products are not readily available and cost-effective which restricts broad penetration of these products into low-and middle-income communities . Thus, an alternative approach is required that will address how commonly available fabrics of biodegradable natural fibres can be used as sanitary pads. This could help billions of women in low-and middle-income countries to improve menstrual hygiene management. Additionally, this paper is in line with the broader “MHM in Ten” 2014-2024 global agenda of providing girls with support in the school environment to manage menstruation with dignity, safety and comfort. Specifically, it responds to the recommendations to advance the agenda of ‘Priority 1: Build a strong cross-sectoral evidence base for MHM in schools for prioritization of policies, resource allocation, and programming at scale’. It could address the need for ‘natural experiments’ to understand the funding and policy implications of MHM programs in schools that provide menstrual products to girls in middle and low income countries . Further, this study which provides new preliminary evidence in the area of health, efficacy, environmental safety of menstrual products is in line with the global consensus regarding adolescent menstrual health in low-and middle income countries and suggestions for future action and research .
The aim of this investigation is to analyse the absorption capacity of readily available, natural biodegradable materials for the purpose of feminine sanitary hygiene products in low-and middle-income countries. Together with that, strategies of using these natural biodegradable materials in a cost-effective way by involving local NGOs were also discussed.
Biodegradable materials for sanitary pads
The most common material used for commercial sanitary pads is superabsorbent polymer (SAP). The challenges regarding SAP are that it is expensive, and the production is more technical, requiring a high level of capital and complex machinery.
In contrast to SAP, natural plant fibres are cellulose-based and attract water which make them highly absorbent. The structure of plant fibres changes dimensions with changing moisture content because the cell wall contains hydroxyl and other oxygen containing groups that attract moisture through hydrogen bonding. Moisture swells the cell wall, and the fibre expands until the cell wall is saturated with water. Beyond this saturation point, moisture exists as free water in the void structure and does not contribute to further expansion. Superabsorbent polymer can absorb up to 200 times of its own weight of water . Cotton fibres, from cotton plants, typically hold water up to 24-27 times their own weight .
Linen fibres, which are obtained from the flax plant, have less absorbency than cotton fibres . Cotton terry cloth, where cotton fibres are woven in loops, is more absorbent than standard cotton. The surface area of the loops is designed to absorb liquids and the ability of absorption is driven by fabric weight, thickness, and pile yarn twist . Hemp or industrial hemp is a natural fibre from a variety of the Cannabis sativa plant. Hemp has mildew resistance, fast water absorbency and good wicking properties [18, 19]. Hemp is more water absorbent than cotton . Bamboo fibre or bamboo textile is another highly absorbent material. Bamboo fibre is also more absorbent than cotton . The cross-section of the fibre is filled with numerous micro-holes and micro-gaps. Bamboo fibres’ cellulose composition consists of crystalline and hierarchal structures which differs from the other natural materials. Bamboo is also found to contain a unique anti-bacterial and bacteriostasis bio-agent called ‘Bamboo Kun’. This feature of bamboo fibre makes it useful for sanitary products, as it will not gather as much bacteria as other alternatives, when worn for extended periods. Bamboo fibre appears to be an excellent alternative to SAP’s, as it is highly absorbent, biodegradable, has excellent ventilation and several anti-bacterial properties. However, processing of bamboo fibre and sealing it into a sanitary pad is expensive, which in turn increases the user cost. In view of that, direct usage of bamboo wadding fabric instead of bamboo fibres was investigated in this current study. Bamboo wadding fabric has been used previously only inside quilts and children's coats.