The purpose of this study is the fundamental study to develope basic slacks pattern for pregnant women by analysing characteristics of the lower half of their body. The results are as followers: 1. The pregnancy has changed almost all items including the waist height, lengths and etc. and changed proportion of body by accumulation of fat. 2. The changes of the waist circumference and flat figure from waist to hip could be found by analysing the body shell (pregnant women from five months pregnance to one month after delivery). 3. The postures of five month-pregnant women were compared with those of six, seven, eight, and nine month-pregnant women, and with those of one month after delivery. The waist height has been increased till the middle of pregnancy but lowed till the end of the pregnancy.