The clash marked a fresh escalation between Washington, which has threatened the regime over its alleged use of chemical weapons, and Damascus, which labelled the latest incident in eastern Syria a "war crime".
Among them was the young daughter of Abu Raad, a shell-shocked man from Eastern Ghouta.
Medics in Idlib were also treating casualties from Tuesday - the bloodiest day in the conflict for several months, when 78 people were killed. He described seeing shell-shocked children brought in to the clinic, sitting in silence even though they were badly wounded.
The organisation said the situation had reached "extreme" levels which "we haven't seen before". The Syrian Observatory for Human Rights put Tuesday's death toll at 70 in what it said was the highest it had recorded since December.
The strikes killed over 30 civilians on February 5, according to the monitor groups.
"Ghouta is drowning in blood", said a doctor in Arbeen, one of the towns in the region in which 100 people were wounded and at least 14 killed, including a rescue worker and several children.
"Children and teachers are terrified that at any moment they could be hit".
"There must be an immediate halt to the fighting and an end to the siege".
The onslaught targeted a number of areas in the city and its countryside after the rebels shot down a Sukhoi Su-25 warplane, killing its pilot on Saturday.
Fighting also raged in the northwestern province of Idlib, where the United Nations said the violence "made a mockery" of the de-escalation zones agreed a year ago in a bid to pave the way for an end to the war.
Syrian state-run media said the Syrian army was responding to a shelling attack in Damascus by "armed groups" - an attack that they say killed five people - including two children - and injured 13 others. A resolution should also demand immediate access for United Nations representatives and independent investigators to Rakhine State, including the Special Rapporteur on the situation of human rights in Myanmar and members of the fact-finding mission mandated by the Human Rights Council. "We don't know what to say". Russian Ambassador to the U.N. Vassily Nebenzia said Thursday that the proposed ceasefire is "not realistic", Agence France-Presse reported.
The Crisis Group analyst suggested that Russian Federation brokers a deal within which Israel will acquiesce to Iran's influence in Damascus and will come to terms with the Syrian state's symbolic return to south-western Syria, where the first protests of the 2011 uprising began.
The US Central Command said the coalition acted in self-defence after pro-government forces moved on an area under the control of the Kurdish-led Syrian Democratic Forces.
"If we say and repeat that there are chemical attacks, we build an obligation to react, " he said, adding: "We are not far away from that". Since 25 August a year ago the Rohingya have endured widespread and systematic attacks by government security forces, including mass killings, rape, torture, and forced displacement.