It helps to maintain a constant temperature around the fetus, cushion it from injury, and allows for proper fetal movement and organ development.

[3] The cause of anhydramnios is not always clear, but several factors can contribute to its development such as fetal renal abnormalities or placental insufficiency.

By the second trimester, the fetal kidneys start to produce urine which becomes the main source of the amniotic fluid for the remainder of the pregnancy.

[4] For this reason, discrepancies between fundal height measurements and gestational age can be a clinical indication of amniotic fluid abnormality and should be evaluated by ultrasound.

[15] There are two methods that can be used to make the diagnosis: the amniotic fluid index (AFI) and the single deepest pocket (SDP) measuremen.

[1] In a multiple gestation pregnancy, measuring a single deepest pocket is the most accurate determination of adequate amniotic fluid levels.

[2] After initial diagnosis of oligohydramnios has been made, the next step is to perform a thorough history and physical exam, followed by diagnostic testing if indicated.

There is uncertainty about the procedure's safety and efficacy, and it is recommended that it should only be performed in centers specializing in invasive fetal medicine and in the context of a multidisciplinary team.

[5] In case of congenital lower urinary tract obstruction, fetal surgery seems to improve survival, according to a randomized yet small study.

This includes a weekly non-stress test (NST) and single deepest pocket (SDP) assessment which is also referred to as the modified BPP.

[1] Complications may include cord compression, musculoskeletal abnormalities such as facial distortion and clubfoot, pulmonary hypoplasia and intrauterine growth restriction.