The use of chemical weapons by the Syrian regime against rebel-held areas is resulting in genetically malformed babies, according to doctors.
One medic said the incidence of stillborn babies at a clinic for refugees was running at more than one in 10 births, while videos posted by activists showed badly disabled infants being born.
The parents of a baby born with a deformed face, who died last week near Damascus, have also said they are convinced that exposure to gas is responsible. The baby girl, Fatma Abdul Ghafar, from the suburb of Eastern Ghouta, was born on Tuesday of last week but died nine hours later after doctors decided her life was not viable.
Mahmoud Abdul, 26, the father, said that the doctor supervising the birth had said exposure to chemical weapons was the most likely explanation for her deformity. His wife inhaled gas during a notorious attack on the suburb last August, while she was in her first month of pregnancy, but had appeared to recover.
"When the chemical attack happened Marwa, my wife, smelled gas and was ill," he said. "We took her to a medical point where she was showered and got better. The baby was born in a very bad way. So she died the next morning."
Mr Ghafar dismissed suggestions that hereditary defects or other environmental factors could have been the cause.
Neither his family nor that of his 17-year-old wife had suffered previous incidents of deformities.
More than 1,000 people including women and children were killed on August 21 when regime forces dropped chemical weapons on two separate areas of Ghouta in an effort to dislodge entrenched rebel resistance.
Some 3,600 people affected were treated for symptoms of sarin gas poisoning, according to a report by the charity Medecins Sans Frontieres.
Ali Baz, the head of a network of citizen journalists in the area called Syria Mubashr said: "Doctors who examined the case of the dead baby confirmed that it is the first case after the use of the chemical weapons at this region."
A second child died in the same area on Tuesday according to Beirut's Daily Star newspaper.
In another case a four-month-old baby girl called Jood is receiving treatment in a hospital in Idlib province after she was born with the bottom half of her left leg and several fingers missing.
Jood's mother was two months pregnant when she was exposed to gas during fighting in Homs last July.
Nidhal Shikhani, another activist, said there were widespread fears the sarin attacks on Damascus had caused abnormalities in newborns.
"These distortions are the result of the chemical weapons used by the Syrian regime last August," said Mr Shikhani.
Even outside the immediate area, the effect of the attacks is marked.
"We have noticed an increase of the percentage of stillborn deliveries and increasingly a need to use incubators, as well as growth retardation," said Kasem al-Zein, a doctor who runs medical operations for Syrians in Arsal, a border town in Lebanon.
"We are receiving pregnant women in Arsal from many areas such as Qusair, Homs, Kalamoon, and [outer] Damascus, they come across the border for giving birth but in some cases the result is tragedy. We are receiving around 100 births a month in Arsal, about 12 per cent in the average out of them are stillborn," he said.
"The problems for newborn children are mostly occurring in women who were exposed to the chemical weapons, but also we have noticed that all women who lived in areas exposed to shelling by barrels and missiles are suffering foetal diseases."
The British Foreign Office said the reports of deformation and deaths of newborns added to the urgency of efforts to remove chemical weapons in Syria.
"We are aware of these reports and images and are deeply disturbed by the suffer of the families concerned," a spokesman said.