I have just learned with pain and consternation the death of 11 newborn babies in the fire that occurred in the neonatology department of the Mame Abdou Aziz Sy Dabakh hospital in Tivaouane," Sall said in a tweet without giving further details about the fire.
"To their mothers and their families, I express my deepest sympathy," Sall, who was on a state visit in Angola, added.
Senegal health minister Abdoulaye Diouf Sarr said on private Senegalese television TFM that "according to preliminary investigation, a short circuit triggered the fire".
Sarr, who was in Geneva for the World Health Assembly, said he would cut short the trip and return to Senegal immediately.
Demba Diop Sy, the mayor of Tivaouane, one of Senegal's holy cities and a transport hub, said police and fire service were still at the hospital, but did not provide further details.