The world's largest retailer, Wal-Mart, is reviewing its marketing strategy, after withdrawing from sale a 'pregnant' children's doll.

The doll, Midge, is known to children around the world as the oldest friend of the best-selling Barbie doll.

The pregnancy-themed happy Family dolls complement children's strong interests in family relationships Jo Ann Farver, US psychologist

Wal-mart was selling Midge as part of a Happy Family set that also included her husband Alan and their 3-year-old son Ryan.

"Customers said they were not happy with the pregnant Midge doll so Wal-Mart removed the entire happy Family set," spokeswoman Melissa Berryhill said.

'Pregnancy-themed' dolls

The pregnant version of Midge wears a pink skirt, a tiny wedding ring and a detachable stomach with a curled-up baby inside.

The doll - which says "Mommy loves her new baby" - comes with a cradle and other baby gear.

The toy's maker, Mattel, said on its Barbie.com web site that dolls like Midge "can help parents discuss pregnancy without having to have graphic descriptions of the reproductive process".

The company also posted an interview with a psychologist explaining the value of the Happy Family set.

"The pregnancy-themed happy Family dolls complement children's strong interests in family relationships, and supports their social and emotional development," the psychologist, Jo Ann Farver, said.