Police recovered the hanging body of a pregnant woman from Solai Market area in Bhakuta union of Savar early Saturday.
The deceased was identified as Ratna, 30, wife of Khairul Islam, a lineman of Palli Bidyut Samity.
Locals said that family members found the body of 9-month pregnant Ratna hanging from a ceiling fan at her room and informed police.
Later, police recovered the body and detained Khairul.
Sujan Biswas, sub-inspector of Bhakurta Police Camp, said an autopsy would be done to determine whether the incident was murder or a suicide.
A case was filed with Savar Model Police Station.