Some 185 refugee children have died in the Aegean Sea between Turkey and Greece in 2015 so far UNICEF said.
"In the Aegean (Eastern Mediterranean), about 30 percent of the deaths this year have been of children. This is currently 185 children out of a total of 590 deaths in the Eastern Mediterranean this year," UNICEF spokesperson Sarah Crowe told Anadolu Agency on Tuesday.
Images showing the body of drowned three-year-old Syrian toddler Aylan Kurdi provoked worldwide reaction when they were released last September.
However, since then at least 90 refugee children have died in the Aegean Sea in October alone.
One in five of these victims were aged two-years-old or less. Overall, UNICEF says five percent of the fatalities in the Eastern Mediterranean were under the age of two.
Most of the refugee children who have died this year are from Syria, Afghanistan and Iraq, and were under the age of 12, according to UNICEF.
According to UNICEF statistics, 30 percent of the 3,500 deaths in the Mediterranean Sea this year were children, meaning more than 1,000 youngsters died in perilous sea voyages in 2015 so far.
However, the charity is reluctant to give definitive data on the tragedies.
"We do not have a total figure of children deaths for the whole Mediterranean because data on age of those who die are poor in the Central Mediterranean," Crowe said.
"Generally many more people [of all ages] have died in the Central Mediterranean: 2,890 so far (or about 81% of all deaths in the Med).
“We don’t know what share of those who died are children though. It is likely a lower share than in the Eastern Mediterranean as fewer children travel through the Central Mediterranean," Crowe added.
According to UNICEF, since the beginning of this year, more than one in five of the over 870,000 refugees and migrants crossing the Mediterranean are children.
Between Jan. and Sep. 2015, more than 200,000 child applications for entry to the EU were received, UNICEF said.
A quarter of all these child applicants originate from Syria, followed by Afghan children on 18 percent.
According to the International Organization for Migration, the total number of people crossing the Mediterranean Sea in 2015 has reached 878,000, which is four times higher than last year.
So far, some 3,563 people have died crossing the Mediterranean; 589 of these deaths have been in waters between Greece and Turkey.