An amniotic fluid index of 70 at 34 weeks of pregnancy is not normal, suggesting that the amniotic fluid is low. Most of the hospitals use ultrasound to find out the status of amniotic fluid and adopt the “amniotic fluid index method” to determine whether the amount of amniotic fluid is normal or not. The method is to divide the uterus into four quadrants at right angles to the umbilical level and the white line of the abdomen, measure the vertical diameter of the largest amniotic fluid pool in each quadrant, and the sum of the four is the amniotic fluid index. The 34th week of pregnancy is the middle to late stage of pregnancy, when the amniotic fluid is increasing and is the most abundant. The amniotic fluid index should be ≥80 mm when measured at 34 weeks; if it is <80 mm, it is considered oligohydramnios, and if it is <50 mm, it is considered hypohydramnios. Low amniotic fluid may be caused by insufficient water intake or medication effects, hypovolemia, gestational hypertension and other conditions, and may also be caused by fetal urinary tract abnormalities or placental insufficiency. It is recommended to drink plenty of water, go to the hospital for regular checkups, and treat any abnormalities under the guidance of the doctor.