The cross-sectional survey on 700 subjects of couples of childbearing age in 3 commune groups in 5 districts/city of Nam Dinh province on the status of the sex ratio at birth. Group I represents the districts whose economy is mainly based on agriculture, group II represents the districts whose economy is mainly based on the sea and the III group is the city representing in urban areas. The results showed that: the percentage of study subjects knew diagnostic services, fetal sex selection using ultrasound method in the three groups was: 60.4 percent
83.9 percent and 86.4 percent, respectively. Reasons to have more children because there is no boys were: 42.6 percent
32.4 percent
32.8 percent. Percentage of subjects who intended to have abortion when the sex of the fetus is not as their desire in commune group II is the highest, at 52.9 percent. The percentage of study subjects usingprenatal fetal sex diagnostic in the group III was highest, with74.3 percent. The rate of the fetal sex diagnosis by ultrasound method in the three groups was 88.3 percent
96.0 percent and 97.1 percent, respectively.