Is an amniotic fluid index of 55 mm normal?
Nov 14, 2025
Source: Cainiu Health
Dr. Zhang Lu
Introduction
Under normal circumstances, whether an amniotic fluid index of 55 mm is considered normal depends on the gestational week. If any discomfort symptoms occur, it is recommended to promptly seek medical evaluation and treatment at a正规 hospital. Daily water intake should be sufficient, maintained at 1,500–2,000 milliliters, to promote amniotic fluid production. A light and nutritious diet is advised, with increased consumption of water-rich fruits and vegetables, while avoiding spicy and irritating foods.
Generally speaking, whether an amniotic fluid index (AFI) of 55 mm is normal depends on the gestational age. If any discomfort occurs, it is recommended to seek timely medical evaluation and treatment at a正规 hospital. The detailed analysis is as follows:
If in the late stages of pregnancy, especially after 37 weeks, an AFI of 55 mm should be evaluated in conjunction with fetal condition; in some cases, close observation may be temporarily appropriate. At this stage, the fetus is largely mature. If fetal heart monitoring is normal, there are no signs of intrauterine hypoxia, and the amniotic fluid volume shows no continuous decline, close monitoring under a doctor's guidance may be conducted, with regular ultrasound examinations to track changes in amniotic fluid and fetal status.
If in mid-pregnancy or early late pregnancy, an AFI of 55 mm is considered abnormal. During this period, the normal range for AFI is 80–180 mm; values below 80 mm indicate oligohydramnios, and 55 mm is near the lower limit of this condition. Severely reduced amniotic fluid may lead to complications such as fetal limb adhesions or intrauterine distress, so further evaluation is necessary to determine potential underlying causes such as fetal urinary tract malformations or placental insufficiency.
In daily life, maintain adequate hydration by drinking 1500–2000 mL of water per day to support amniotic fluid production. Eat a light, nutritious diet rich in fruits and vegetables with high water content, and avoid spicy or irritating foods. Avoid strenuous activities, excessive fatigue, and maintain a regular sleep schedule. Closely monitor fetal movements, and seek medical attention promptly if fetal movements suddenly increase or decrease. Strictly follow medical advice for regular prenatal checkups and cooperate with all recommended examinations. Do not self-medicate or blindly supplement nutrients.
