The decree published this week allows corrective surgery for hermaphrodites and people born with certain genital deformities, but not for people who are physically of one sex and request gender reassignment surgery.
"The reassignment of gender for those who are complete in terms of gender" is forbidden, says the text of the decree, which adds that the new measure aims to "ensure that everyone can live in his/her correct gender."
Nguyen Huy Quang, deputy head of the health ministry's legal department, said the decree "still prohibits sex change for those who are already in their original gender," as determined by medical and genetic testing.
The decree would ensure the privacy of, and prohibit discrimination against, people who have undergone gender reassignment surgery, and also require medical proof when they register with authorities under their new gender.
Statistics on people seeking gender reassignment surgery are not available in Vietnam, but several transsexuals are known to have travelled to Thailand to undergo sex-change surgery.