A police spokesman said all three were rushed to King Edward VII Memorial Hospital in a private vehicle to be treated for injuries not believed to be life-threatening.
One of the female victims remains in hospital.
Police say the incident occurred just before 1am at a birthday celebration at John Smith’s Bay in Smith’s Parish.
“It is understood an altercation broke out around 12.30am and resulted in a 20-year-old male and two 19-year-old females being injured with what was believed to be a bladed article,” the spokesman said.
Police are now appealing for witnesses or anyone with mobile phone footage of the incident, to contact 211, the Criminal Investigation Department at 247-1744, or the confidential Crime Stoppers number on 800-8477.