#146 Management of Late-Term and Postterm Pregnancies

Question 1

What is the definition of a postterm pregnancy?

Answer 1

Pregnancy that has reached or extended beyond 42w0d from LMP

Question 2

What is the definition of a late-term pregnancy?

Answer 2

Pregnancy between 41w0d and 41w6d

Question 3

What is the incidence of postterm pregnancy in the US?

Answer 3

5.5%

Question 4

What are risk factors for postterm pregnancy?

Answer 4

Male fetus, obesity, nulliparity, prior postterm pregnancy. Certain fetal disorders: anencephaly and placental sulfatase deficiency

Question 5

True or false: delivery after 42 weeks is associated with increased rate in NICU admissions?

Answer 5

True. Odds ratio 2.05

Question 6

True or false: postterm pregnancy is associated with increased risk of neonatal convulsions?

Answer 6

True

Question 7

True or false: postterm pregnancy is associated with lower risk of meconium aspiration syndrome?

Answer 7

False. Higher rates

Question 8

True of false: Postterm pregnancy is associated with increased risk of 5-minute Apgar scores of less than 4?

Answer 8

True

Question 9

True or false: postterm fetuses have a higher rate of macrosomia than term fetuses?

Answer 9

True. Twofold increased risk. Although most are appropriately grown

Question 10

What are signs of postmaturity syndrome?

Answer 10

Decreased subcutaneous fat, lack vernix and lanugo, meconium staining of amniotic fluid, skin, membranes, and umbilical cord.

Question 11

What percentage of postterm pregnancies are complicated by postmaturity syndrome?

Answer 11

10-20%

Question 12

True or false, rate of stillbirth increases after 41 weeks?

Answer 12

True

Question 13

What are maternal risks associated with postterm pregnancies?

Answer 13

Increased risk of severe perineal laceration, infection, PPH, and cesarean delivery. Maternal anxiety.

Question 14

What inventions (apart from IOL/CS), decrease the incidence of late-term and postterm pregnancies?

Answer 14

First, accurate dating (rates of postterm pregnancies decreased from 9.5% to 1.5% when dating by LMP confirmed w/ US). Membrane sweeping also decreases the incidence

Question 15

Is GBS colonization a contraindication to membrane sweeping?

Answer 15

No, not enough clinical evidence. Use clinical judgement.

Question 16

Is antepartum fetal testing recommended in late-term and postterm pregnancies?

Answer 16

No RCTs that demonstrate decrease in perinatal morbidity or mortality. Initiation of antepartum fetal surveillance at or beyond 41w0d may be indicated.

Question 17

How frequently should you perform antenatal fetal testing in postterm pregnancies?

Answer 17

Data insufficient, but possible superiority of twice-weekly testing compared to once weekly

Question 18

When should labor be induced for late-term and postterm pregnancies?

Answer 18

IOL between 41w0d and 42w0d can be considered. IOL after 42w0d and by 42w6d is recommended given evidence of an increase in perinatal morbidity and mortality

Question 19

True or false: there is an increased risk of uterine rupture associated with TOLAC attempted beyond EDD

Answer 19

False

Question 20

What is the overall failure rate of TOLAC prior to 40 wks and after 41 wks?

Answer 20

22.2% prior to 40wks. 35.4% after 41 weeks