Oligohydramnios is defined by an amniotic fluid index less than:

Oligohydramnios is defined by an amniotic fluid index less than:

• A. AFI 5 cm
• B. AFI 15 cm
• C. AFI 25 cm
• D. AFI 35 cm

Answer: (A)

Amniotic fluid index is the sum of the deepest vertical pockets in all four uterine quadrants on ultrasound. Normal AFI values are roughly in the mid range, and when the AFI falls to 5 cm or less, that defines oligohydramnios. In this context, an AFI of 5 cm or below indicates too little amniotic fluid. The other values correspond to higher fluid levels: 15 cm is within normal limits, 25 cm borders on polyhydramnios, and 35 cm is clearly polyhydramnios. So the threshold for oligohydramnios is an AFI of 5 cm or less.

Amniotic fluid index is the sum of the deepest vertical pockets in all four uterine quadrants on ultrasound. Normal AFI values are roughly in the mid range, and when the AFI falls to 5 cm or less, that defines oligohydramnios. In this context, an AFI of 5 cm or below indicates too little amniotic fluid. The other values correspond to higher fluid levels: 15 cm is within normal limits, 25 cm borders on polyhydramnios, and 35 cm is clearly polyhydramnios. So the threshold for oligohydramnios is an AFI of 5 cm or less.