The Observatory said 20 children and 15 women were among those killed.
The suburbs have been subjected for weeks to bombardment that has killed and wounded hundreds of people.
Opposition activists said government forces had brought in reinforcements in preparation for a wider offensive on the area.
The United Nations children’s agency, Unicef, issued a one-page statement that was largely blank. “Do those inflicting the suffering still have words to justify their barbaric acts,” the statement read. It was followed mostly by white space because “we no longer have the words to describe children’s suffering and our outrage.”