Research aims: To describe the knowledge, attitude and practice of fetal sex selection of couples in Bac Giang province. Objectives: 1,164 couples giving birth for 5 years, (from the beginning of January 2007 to the end of December 2011), in 3 districts with high sex ratio at birth in Bac Giang province, namely, Luc Nam, Lang Giang and Viet Yen. Methods: A horizontal (prospeqive, retrospective) description study. Results: (1) Knowledge: The knowledge of objectives about social influences of fetal sex selection is limited (83.6 percent know that it leads to having more boys than girls
12.6 percent think that it has no influence on the society), while 28 percent know about fetal sex selection methods
(2) Attitude: A high ratio of objectives want to have a boy baby (54.6 percent)
(3) Practice: A high ratio of objectives utilize the fetal sex selection methods in next birth delivery (18.0 percent).