A radical increase in the number of multiple births over the past 30 years, due to the rising popularity of fertility treatments in Greece, poses a considerable threat to the health of babies and mothers, doctors warned yesterday. According to Athens University Professor of Pediatrics Andreas Constantopoulos, babies born in multiple births face twice the risk of developing irregularities in vital organs, such as the heart and kidneys, than single babies. Furthermore, the mortality rate among mothers is between two and three times higher (10-15 per 100,000) in multiple births than in single births. Speaking at a press conference ahead of a national pediatrics congress that opens in Thessaloniki today, Constantopoulos said in vitro fertilization attempts should focus on transplanting only one fertilized egg at a time – even if that necessitates multiple attempts – as opposed to three to five at the same time. Since the early 1970s, there has been a 150-percent increase in twin births, 535 percent in triplets, 1,010 percent in quadruplets and 550 percent in quintuplets.