Madonna's son David returned with her to Malawi last month
Madonna's appeal to overturn a judge's decision which would allow her to adopt a second Malawian child is to be heard on 4 May, a court official said.
Joseph Chigona told the AP news agency the case involving 3-year-old Chifundo James would come up before three Supreme Court of Appeal judges.
A spokesperson for the singer said she was still being monitored by doctors following a fall from her horse.
Madonna suffered minor injuries after the fall in New York on Saturday
Chifundo James, whose name translates into English as Mercy, has been living in the same orphanage from which Madonna took David Banda in 2006. Her adoption of the boy, now aged 3, was made official two years later.
The 50-year-old singer also has two biological children, Lourdes and Rocco. All three travelled to Malawi with Madonna when she attempted to adopt Mercy in March this year.
Madonna's application was rejected because of a requirement that prospective parents be resident in the southern African state for 18 to 24 months.
Her Malawian lawyer, Alan Chinula, said he was hopeful of a successful appeal as the initial rejection was based "on an archaic law of over 50 years ago".