Encyclopedia
Perinatal period
The perinatal period begins at the 22nd week of gestation (154th day) of fetal life (at this time, body weight normally amounts to 500 grams) and ends seven days after birth
Source: "PROTECTION OF REPRODUCTIVE HEALTH OF WORKERS. BASIC TERMS AND CONCEPTS"
(approved by the Ministry of Health of Russia on October 2, 2003 No. 11-8/13-09)