Sanitary pads are common external hygiene products designed to absorb and contain fluid discharged from the body. They consist of a multi-layered structure and are secured to the inside of underwear with an adhesive strip. Their primary function is to draw liquid away from the body, trapping it within the product’s core to prevent leakage and maintain dryness.
Managing Menstrual Flow
The most frequent application for sanitary pads is the management of menstrual flow, which varies significantly in volume throughout the cycle and between individuals. Manufacturers categorize pads by absorbency levels—light, regular, heavy, and overnight—to match these fluctuations. Using the correct absorbency is a simple way to prevent leaks and maximize comfort during different phases of the period.
Pads designed for a regular flow are suitable for average days, offering a balanced level of protection and thickness. For the heaviest flow days, pads labeled “heavy” or “maxi” contain a greater concentration of absorbent material and are often longer for increased coverage. Overnight pads are specifically engineered with an extra-long and wider shape, particularly at the back, to provide protection when the wearer is lying down.
The Design and Mechanism of Absorption
The layer that makes direct contact with the skin is the topsheet, typically made from a perforated or non-woven material designed to quickly wick moisture away. This immediate transfer of fluid ensures the surface remains relatively dry, which helps reduce skin irritation.
Beneath the topsheet lies the absorbent core, the central component responsible for fluid retention. This core is often a blend of cellulose pulp, which acts as a sponge, and super-absorbent polymers (SAPs), commonly sodium polyacrylate. These polymers are capable of absorbing hundreds of times their own weight in liquid, instantly transforming it into a contained gel to prevent back-flow and leakage. The final layer is the backsheet, an impermeable, plastic-like film, usually made of polyethylene, that acts as the last barrier to stop the absorbed fluid from reaching clothing. Many pads also feature adhesive wings, which are flaps that fold over the edges of the underwear to provide extra security against shifting and side leaks.
Postpartum Recovery and Other Applications
Beyond menstruation, pads are used for several other hygiene needs. Following childbirth, pads manage lochia, which is the heavy, prolonged vaginal discharge of blood, mucus, and tissue that occurs as the uterus heals. The initial flow of lochia is often much heavier than a regular period, necessitating the use of large, thick, and highly absorbent maternity-style pads.
Panty liners, which are ultra-thin and smaller versions of full pads, address much lighter fluid management. They are frequently used to maintain freshness by absorbing normal daily vaginal discharge. Panty liners also provide protection for light spotting between periods or during the final days of a period. Additionally, they are sometimes used to manage minor bladder leaks associated with stress incontinence.
Proper Usage and Disposal Guidelines
Correct usage of a sanitary pad begins with peeling off the paper strip that covers the adhesive on the back of the pad. The sticky side is then placed centrally within the gusset of the underwear to ensure a secure fit. If the pad has wings, they are folded over the edges of the underwear to anchor the product firmly in place and offer side protection.
Pads should be changed regularly to maintain hygiene and prevent odors, typically every three to five hours, or more frequently if the flow is heavy. For disposal, the used pad must first be wrapped tightly, either in its wrapper, the wrapper of a new pad, or a few sheets of toilet paper. The wrapped pad should then be placed into a designated waste receptacle, such as a trash can or a sanitary bin. Never flush a used sanitary pad down the toilet, as their materials do not dissolve and will cause plumbing blockages.