Polyhydramnious & Oligohydramnious

Question 1

What is polyhydramnios?

Answer 1

• deepest vertical pocket >8cm
• amniotic fluid index >25cm

Question 2

What are the degrees of polyhydramnios?

Answer 2

Mild
- DVP = 8-9.9cm
- AFI = 25-29.9cm

Moderate
- DVP = 10-11.9cm
- AFI = 30-34.9cm

Severe
- DVP = 12 or more
- AFI = 35cm or more

Question 3

What are the causes of polyhydramnios?

Answer 3

Maternal
- diabetes
- chorioangioma
- Rh isoimmunization

Fetal
- idiopathic
- congenital malformations
- twin-twin transfusion syndrome
- congenital infections

Question 4

What is the presentation of polyhydramnios?

Answer 4

• abdominal distention & abdominal discomfort
• tenderness
• fundal level > expected
• difficulty in palpating fetal parts
• shortness of breath

Question 5

What are the risks of polyhydramnios?

Answer 5

• placental abruption
• preterm birth
• cord prolapse
• malpresentation

Question 6

How is polyhydramnios managed?

Answer 6

1- know the cause
2- detailed fetal anomaly scan
3- ensure good glycemic control in diabetic patients
4- maternal antibody test for viral infection
5- amnio-drainage to relieve maternal discomfort (1-2L are removed within 20-30mins)
6- indomethacin (NSAID) to reduce production of fetal urine

Question 7

What is the definition of oligohydramnios?

Answer 7

< 2cm by deepest vertical pocket
< 5cm by amniotic fluid index

if there is no measurable pole of amniotic fluid -> anhydramnios

Question 8

What are the causes of oligohydramnios?

Answer 8

Maternal
- PROM
- Post date
- placental insufficiency

Fetal
- twin to twin transfusion
- renal agenesis
- NSAIDs, ACEI, ARBs
- urine tract obstruction

Question 9

How is oligohydramnios clinically diagnosed?

Answer 9

• easily felt fetal part abdominally
• fundal height less than date
• if before 24 weeks -> lung hypoplasia & limb deformity
• renal agenesis & bilateral multicystic kidneys are lethal
• fetal compromise during labour

Question 10

How is oligohydramnios managed?

Answer 10

oligohydramnios diagnosed before 36 weeks with no fetal abnormality in anatomy or growth -> expectant + fetal surveillance -> delivery between 36-37 weeks

Question 11

What are the risks of oligohydramnios?

Answer 11

• Maternal -> 2 fold increase risk in C section
• Fetal -> prematurity, low apgar score <7 at 5 min

Question 12

What are the risk factors for macrosomia?

Answer 12

• gestational diabetes
• prolonged pregnancy
• obesity/increase in pregnancy weight gain
• male fetus/multiparity

Question 13

What are the maternal risks of macrosomia?

Answer 13

• operative vaginal delivery
• perineal lacerations
• postpartum hemorrhage (uterine atony)
• emergency C section
• pelvic floor injury

Question 14

What are the risks of macrosomia on the fetus?

Answer 14

• shoulder dystocia
• birth injury
• asphyxia
• Erb’s palsy
• hypoglycemia
• NICU admission

Question 15

How is oligohydramnios managed?

Answer 15

• if birth weight is >4.5kg in a diabetic mother & > 5kg in a nondiabetic mother -> elective C section
• early induction whenever macrosomia in suspected