no, the material for bras and bikini is different.
most bra has metal(or something hard) at the bottom to support the
breast, pushing in up, to make them more firm. Most bikinis dont
have that.
most bikinis are made of more elastic material than those for
making bras, for the reason that when u swin or play some sports on
the beach/pool side, the bikini will stick to your breast, to
reduce the change of showing your nipple to others. For bras, the
bottom part is tightly stick to the breast, but the top part is
not.
