Post-Term Pregnancy

Clinical description

Post-term pregnancy is defined as a pregnancy ≥ 42 wks gestation. It is associated with increased risk of meconium aspiration, IUFD, oligohydramnios and fetal distress.

It is also associated with risk of induction of labour and caesarean delivery.

Accurate pregnancy dating is critical so that interventions can be done - or avoided - as indicated.

Signs and symptoms

History/Exam/Investigations:see section on Pregnancy Dating Criteria

Treatment

• If GA 40 wks, then conservative management until delivery is indicated for other reasons (i.e. preeclampsia) or GA

≥ 42 wks

• Do cervical stretch and strip membranes at 40+ weeks if no contraindications
• Assess amniotic fluid volume with US

 If oligohydramnios, then admit for induction of labour (IOL)  If absent fetal movement (on US or maternal perception?), then admit for IOL regardless of fetal cardiac activity  If normal amniotic fluid volume, then instruct patient to monitor fetal kick count, weekly US to monitor AFI and BPP- if normal return at 41+3 wks gestation for IOL

• If GA ≥ 42 wks, then deliver via IOL or cesarean as indicated.