What is the definition of postterm pregnancy?
Postterm pregnancy is pregnancy that has reached or extended beyond 42 0/7 weeks of gestation from the last menstrual period.
What is the incidence of postterm pregnancy?
Approximately 3-12% of pregnancies extend beyond 42 weeks, with variation based on dating accuracy.
How does early ultrasound dating impact postterm rates?
Early ultrasound dating reduces postterm rates from 9.5% to 1.5% compared to LMP-based dating alone.
What are some maternal risk factors for postterm pregnancy?
Maternal risk factors include previous history of postterm pregnancy, placental sulfatase deficiency, nulliparity, advanced maternal age, and maternal obesity (BMI >30).
What fetal factors contribute to postterm pregnancy?
Fetal factors include fetal anomalies like anencephaly, male fetal gender, fetal macrosomia, and certain genetic conditions.
What are the maternal risks associated with postterm pregnancy?
Maternal risks include labor complications, increased cesarean section and instrumental delivery rates, infection risk (chorioamnionitis, postpartum endometritis), hemorrhage risk (uterine atony), and psychological stress/anxiety.
What fetal and neonatal risks are associated with postterm pregnancy?
Fetal and neonatal risks include macrosomia, meconium aspiration syndrome, oligohydramnios, stillbirth, neonatal convulsions, hypoxic-ischemic encephalopathy, and postmaturity syndrome.
How does postterm pregnancy affect stillbirth and perinatal mortality?
Postterm pregnancy increases the risk of stillbirth by 2x, perinatal mortality by 1.5x, and the likelihood of NICU admission by 25x.
What methods are used to assess gestational age?
Gestational age can be assessed by Last Menstrual Period (LMP) calculation, first trimester ultrasound (crown-rump length), second trimester biometry, and clinical assessment integration.
What is the management for post-term pregnancy?
Management includes routine prenatal care, membrane sweeping, induction of labor at 41 weeks to reduce perinatal mortality and morbidity, and delivery at 42 weeks for non-reassuring fetal status or maternal complications.
What are the methods used for labor induction?
Methods include pharmacological methods (prostaglandins, oxytocin), membrane sweeping, amniotomy, and mechanical methods (transcervical Foley catheter).
What is the role of the Bishop score in labor induction?
The Bishop score helps assess the cervix’s readiness for labor and predicts the likelihood of successful vaginal delivery after induction. A higher score indicates a more favorable cervix for induction.
What are the pharmacological agents used in induction of labor?
Pharmacological agents include prostaglandins (PGE1 and PGE2), and oxytocin.
What are the mechanical methods for induction?
Mechanical methods for induction include membrane sweeping, amniotomy, and transcervical Foley catheter.
What are the indications for labor induction?
Indications for induction include postterm pregnancy, preterm premature rupture of membranes (PPROM), hypertensive disorders, fetal compromise, and maternal health conditions like diabetes and hypertension.
What is the role of prostaglandins in labor induction?
Prostaglandins such as Misoprostol (PGE1) and Dinoprostone (PGE2) are used for cervical ripening and to induce labor by stimulating uterine contractions.
What are the complications of using prostaglandins in labor induction?
Complications include uterine tachysystole, meconium passage, hyperstimulation, and uterine rupture (especially in those with previous cesarean section).
What is the mechanism of action of oxytocin in labor induction?
Oxytocin increases uterine contractions, promoting cervical dilation and facilitating labor progression. It is typically used for labor induction or augmentation when the cervix is ripe.
What are the complications of oxytocin use?
Complications include uterine hyperstimulation, fetal distress, amniotic fluid embolism, and water intoxication.
What is the role of membrane sweeping?
Membrane sweeping is used to increase the likelihood of spontaneous labor by separating the membranes from the cervix. It is performed at term when the cervix is starting to dilate and efface.
What are the risks and complications of membrane sweeping?
Complications of membrane sweeping include mild discomfort, risk of infection, and accidental rupture of membranes.
What is amniotomy and what are its benefits?
Amniotomy is the artificial rupture of membranes using an amnihook. It helps observe the color of the liquor and provides access to the fetal scalp for monitoring. It also releases endogenous prostaglandins to increase uterine activity and speed up cervical change.
What is the mechanism of action of amniotomy?
Amniotomy releases endogenous prostaglandins, increasing uterine activity and speeding up cervical change.
What is the preferred method of induction when the Bishop score is advanced?
When the Bishop score is advanced, amniotomy is the preferred method of induction.
