An unusual topic you may think, but one that needs to be discussed.
Most women in western society wear underpants (knickers, panties – whatever you call them). These are “normal” for us. However it may surprise you to know that underpants in this form have only been around since about the 1920s to 1930s. Before then women would wear loose fitting crotchless “bloomers”, and before then, nothing at all. See the underwear section of the Museum of Menstruation for more information on the history of undergarments.
So, in many countries where menstrual product donations would be needed, they may not have underpants either. This may not be because they cannot afford underpants, but may be because the western tradition of wearing such garments is not “normal” for them.
Usually donations of menstrual pads need to be accompanied with donations of underpants as well. This however is problematic, as underwear must be correctly fitting to be useful with pads (particularly cloth pads), and it is impossible to be able to correctly fit every woman if the underpants aren’t specifically sized for them.
If providing underpants, you may like to consider making your own underpants that use a “string bikini” style. That is a style comprised of 2 triangles joined at the crotch, but with sides that tie up.
This allows the sides to be tied to a point that ensured a correct fit for any sized woman, and can be adjustable as she ages or weight changes. As well as providing the needed coverage that allows pads to be worn.
Lunapads has an underwear design similar to this they created – which appears to have loops on the back with the ties on the front – so that the ties are threaded through the loops and then tied together in front (instead of tying at the side like a regular string bikini)