TEGUCIGALPA, Honduras — Ruth Pineda stood with her back to the mirror, the strap of her tank top tucked under her arm, revealing a new tattoo: a heart. Inside were three dolphins jumping over the sea at sunset.

“The big dolphin is me — the mom — and the two little ones are my sons,” she said.

With her tattoo complete after a three-hour session, Ms. Pineda studied the artwork etched into her skin with equal parts admiration and disbelief. The tattoo is her first, and a statement the 43-year-old schoolteacher has wanted to make for nearly 20 years, but never quite felt she could.

For decades, tattoos weren’t just unfashionable in religiously conservative Honduras. They were taboo, with a malevolent history as an identifying feature of deadly gangs like Mara Salvatrucha, better known as MS-13, and the 18th Street gang, or Barrio 18.