Invited to bat, a substantial partnership eluded them after a fiery start but India Women still managed to post a competitive 142 for six at the WACA ground.
India were off to a flying start with opener Shafali Verma (39 of 17 balls) coming out all guns blazing in the Group A game.
However, the Indian innings never got the impetuous after the departure of the 16-year-old, who hit four sixes and two fours in her entertaining knock. Later, Veda Krishnamurthy (20 off 11) hit few lusty blows to help India post a fighting total.
Bangladesh fought through Murshida Khatun (30) and Nigar Sultana (35) but Poonam rattled the middle and lower order with her strikes.
In the end, Bangladesh could manage 124 for eight, giving India Women their second straight win in the tournament.
“The way Shafali and Richa played today, they showed how capable they are for the team. Veda’s innings was turning point. We needed boundaries at that point and she did a great job,” India Women skipper Harmanpreet Kaur said.
Poonam, who had helped India halt Australia’s chase in their opening game as well, was the top bowler again. She scalped Sanjida Islam (10), Fahima Khatun (17) and Jahanara Alam (10) to make it tough for Bangladesh.
Bangladesh needed 49 runs from last five overs but they failed to negotiate Poonam’s flighted deliveries.
The Indian spinner had Fahima caught by Shafali in the first ball of the 16th over while Rajeshwari Gaekwad saw the back of well-set Nigar Sultana.
Poonam then returned to dismiss Jahanara, who stepped out looking for a big hit only to be stumped by Taniya.
The runs dried up and Bangladesh now needed 22 off the final over.
Pacer Shikha Pandey clean bowled Rumana Ahmed with a perfect yorker and writing was clear on the wall.
Earlier, Shafali punished the rival attack with her fluent stroke-making.
Attempting a big one, Shafali skied one off veteran Panna Ghosh and was dismissed, caught by wicket-keeper Shamima Sultana.
This was after fellow opener Taniya Bhatia (2) was sent back by Salma Khathun.
Shafali turned out to be the best scorer in India’s innings.
Jemimah Rodrigues played a sedate yet crucial 34-run knock since hard-hitting skipper Harmanpreet Kaur was already dismissed by Ghosh.
With both Shafali and Harmanpreet cooling their heels back in the dug out, India’s run-rate took a dip.
Jemimah erred in judgement while calling Deepti for a single and was run out.
Richa Ghosh, who replaced Smriti Mandhana in the playing XI, hit two splendid boundaries before holing out to Nahida Akter off Salma Khatun.
The slide continued with Deepti Sharma (11) running herself out following a mix up with Veda Krishnamurthy (20 off 11).