China's Health Ministry on Sunday denied that a milk formula caused the premature breast growth in three baby girls due to its sex hormones.

Samples on Synutra milk and 20 other brands of formula inspected by the ministry and experts from different medical institutes were found to contain safe level of hormones, ministry spokesman Deng Haihua declared, according to Chinadaily.com.

The samples came from the home of one of the baby girls, who allegedly grew breasts after feeding on the milk and from the markets of Wuhan in Hubei province and in Beijing.

Parents of the three girls from Hubei complained about the Synutra milk last month.

Professor Wu Xueyan, an expert in endocrine research at the Peking Union Medical College Hospital, called that the girls' condition as minimal puberty, wherein sensitivity to hormones lead to the growth of breasts.

The three infants did not show premature development of bones or height, and the growth of their breasts was within the normal ranges of minimal puberty, Wu was quoted as saying by Chinadaily.com.