Oligohydramnios
INTRODUCTION:
- An extremely rare condition where the liquor amnii is deficient in amount to the extent of less than 200 mL at term.
- Sonographically, it is defined when the maximum vertical pocket of liquor is less than 2 cm or when amniotic fluid index (AFI) is less than 5 cm (less than 5 percentile)
- With AFI less than 5 cm (below 5th percentile) or more than 24 cm (above 95th percentile) was considered abnormal at gestational age, from 28 to 40 weeks.
- AFI between 5 and 8 is termed as borderline AFI or borderline Oligohydramnios.
ETIOLOGY:
Fetal conditions:
- Chromosomal or structural anomalies
- Renal agenesis
- Obstructed uropathy
- Spontaneous rupture of the membrane
- Intrauterine infection
- Drugs: PG inhibitors,ACE inhibitors
- Postmaturity
- IUGR
- Amnion nodosum
Maternal conditions
- Hypertensive disorders
- Uteroplacental insufficiency
- Dehydration
- Idiopathic.
DIAGNOSIS:
- Uterine size is much smaller than the period of amenorrhea
- Less fetal movements
- Uterus is “full of fetus” because of scanty liquor
- Malpresentation
- Intrauterine growth retardation
- Sonographic diagnosis is made when largest liquor pool is less than 2 cm.
- Visualization of normal filling and emptying of fetal bladder essentially rules out urinary tract abnormality.
- Oligohydramnios with fetal symmetric growth restriction is associated with increased chromosomal abnormality
COMPLICATIONS
Fetal:
- Abortion
- Deformity due to intra-amniotic adhesions or due to compression
- Alteration in shape of the skull, wry neck, club foot, or even amputation of the limb
- Fetal pulmonary hypoplasia
- Cord compression
- High fetal mortality.
Maternal:
- Prolonged labor due to inertia
- Increased operative interference due to malpresentation.
TREATMENT:
- Delivery is made irrespective of the period of gestation.
- Isolated oligohydramnios in third trimester with a normal fetus may be managed conservatively.
- Oral water intake increases amniotic fluid volume.
- In labor, cord compression is common.
- Amnioinfusion (prophylactic or therapeutic) for meconium liquor
Exam Question
- Oligohydramnios is related to Renal Agenesis
- Oligohydramnios is the condition where the liquor amnii is deficient in amount to the extent of less than 200 ml at term.
- Sonographically, oligohydramnios is defined when the maximum vertical pool of liquor is less than 2 cm or when amniotic fluid index (AFI) is less than 5 cm
- Oligohydramnios is seen in Renal agenesis, IUGR & Postmaturity
Don’t Forget to Solve all the previous Year Question asked on Oligohydramnios
