Rescuers found the bodies of the women aged between 35 and 40 after the tragedy near Madanganj Ghat on Sunday, Sadar Upazila Executive Officer Nahida Bari said.
The authorities could not immediately identify the victims.
Packed with passengers beyond capacity, the launch Sabit Al Asad sank around 6pm, said Mobarak Hossain, a deputy director at Bangladesh Inland Water Transport Authority or BIWTA.
Some of the rescued passengers were brought to Munshiganj General Hospital for treatment.
Citing the survivors, Kabir said the launch was carrying more passengers than its capacity.
Mobarak said the Munshiganj-bound launch from Narayanganj was hit by cargo vessel SK-3 near the under-construction third Shitalakkhya bridge.
A rescue vessel also started for the site, he added. Many of the passengers swam ashore, according to him.
River Police Sub-Inspector Yunus Munshi said from the scene they feared some of the passengers were still unaccounted for.
BIWTA’s Mobarak said the storm forced a brief suspension of launch services at Sadarghat Terminal in Dhaka.