Induction of Labor C. T. Allred, M.D. 8/7/09

Standard Maternal Indications Preeclampsia, eclampsia Preeclampsia, eclampsia Term premature rupture of membranes Term premature rupture of membranes Suspected chorioamnionitis Suspected chorioamnionitis Maternal medical condition (DM, HTN, renal disease, ht. disease, etc.) Maternal medical condition (DM, HTN, renal disease, ht. disease, etc.) Risk for precipitous delivery Risk for precipitous delivery Fetal demise Fetal demise

Standard Fetal Indications Postterm pregnancy (Is it 41 or 42 wks?) Postterm pregnancy (Is it 41 or 42 wks?) Oligohydramnios (AFI < 5) Oligohydramnios (AFI < 5) IUGR IUGR Rh sensitization Rh sensitization Prior term stillborn infant Prior term stillborn infant Known fetal anomalies Known fetal anomalies Not on here is macrosomia, Joe. More on that in a bit. Not on here is macrosomia, Joe. More on that in a bit.

Preventive Labor Indications AMOR-IPAT Active Management of Risk in Pregnancy at Term. Active Management of Risk in Pregnancy at Term. A system that assumes 38 to 41 weeks is the ideal time to deliver. A system that assumes 38 to 41 weeks is the ideal time to deliver. Days are subtracted from 41 weeks depending on the mother’s underlying risk factors. E.G. – wt. gain > 30 pounds, induce 6 days before 41 weeks. Days are subtracted from 41 weeks depending on the mother’s underlying risk factors. E.G. – wt. gain > 30 pounds, induce 6 days before 41 weeks. Relies on confirmation of EDC with US done between 8 and 20 weeks. Relies on confirmation of EDC with US done between 8 and 20 weeks. Relies on cervical ripening. Relies on cervical ripening. One small study shows section rate of 4%!! (retrospective study) One small study shows section rate of 4%!! (retrospective study) Not standard of care at this time. Not standard of care at this time.

AMOR-IPAT references Nicholson, J.M., et al, Grand Rounds: Will active management of obstetric risk lower C/S rates?, Contemporary OB/GYN, 9/1/05 Nicholson, J.M., et al, Grand Rounds: Will active management of obstetric risk lower C/S rates?, Contemporary OB/GYN, 9/1/05 Nicholson, J.M., et al, Active Management of risk... Am J Obstet Gynecol. 2004:191: Nicholson, J.M., et al, Active Management of risk... Am J Obstet Gynecol. 2004:191: Sanchez-Ramos L., et al, Labor induction vs expectant management for postterm pregnancies: a systematic review with meta- analysis. Obstet Gynecol. 2003;101: Sanchez-Ramos L., et al, Labor induction vs expectant management for postterm pregnancies: a systematic review with meta- analysis. Obstet Gynecol. 2003;101:

Maternal contraindications Placenta previa (complete) Placenta previa (complete) Previous classical c-section Previous classical c-section Uterine scar other than LTCS x 1 Uterine scar other than LTCS x 1 Invasive cervical cancer Invasive cervical cancer Relative contraindications: Relative contraindications: 1 LTCS, narrow pelvis, significant maternal medical conditions (cardiac, pulmonary, neuro), polyhydramnios, grand multiparity 1 LTCS, narrow pelvis, significant maternal medical conditions (cardiac, pulmonary, neuro), polyhydramnios, grand multiparity

Fetal contraindications Active maternal genital herpes Active maternal genital herpes Untreated maternal HIV Untreated maternal HIV Transverse lie Transverse lie Vasa previa Vasa previa Severe IUGR with abn. Doppler studies Severe IUGR with abn. Doppler studies Significant hydrocephalus Significant hydrocephalus Specific nonreassuring FHT patterns Specific nonreassuring FHT patterns Relative: presenting fetal part above the inlet Relative: presenting fetal part above the inlet

Risk of induction Unintentional preterm delivery Unintentional preterm delivery To infer fetal maturity (ACOG) – ultrasound measurement before 20 weeks supports gestational age of > or = 39 weeks. To infer fetal maturity (ACOG) – ultrasound measurement before 20 weeks supports gestational age of > or = 39 weeks. FHTs documented as present for 30 weeks by doppler. FHTs documented as present for 30 weeks by doppler. >36 weeks since a positive urine or serum HCG >36 weeks since a positive urine or serum HCG

Risk of induction ACOG Practice Bulletin, # 107, 8/09 ACOG Practice Bulletin, # 107, 8/09 Nulliparous women with unfavorable cervices should be counseled about a TWO FOLD increased risk for c- section Nulliparous women with unfavorable cervices should be counseled about a TWO FOLD increased risk for c- section

Risk of induction Requires continuous electronic fetal monitoring. Requires continuous electronic fetal monitoring. Most agents carry the risk of tachysystole leading to nonreassuring fetal heart patterns. Most agents carry the risk of tachysystole leading to nonreassuring fetal heart patterns. Rupture of membranes > 12 hours increases risk of maternal and neonatal infection. Rupture of membranes > 12 hours increases risk of maternal and neonatal infection.

Risk of induction All of these factors need to be discussed with the mother prior to induction as well as alternatives and those risks. All of these factors need to be discussed with the mother prior to induction as well as alternatives and those risks. Document! Document!

Factors predicting success Bishop score > 5 to 7. Dilation is most important factor. Bishop score > 5 to 7. Dilation is most important factor. Gestational age. Gestational age. Multiparity. Multiparity. Lack of factors leading to large baby/uteroplacental insufficiency Lack of factors leading to large baby/uteroplacental insufficiency

Cervical ripening Leads to an increased likelihood of successful induction if Bishop > 5 in multips, > 7 in primips. Leads to an increased likelihood of successful induction if Bishop > 5 in multips, > 7 in primips. Multiple methods: Membrane stripping Amniotomy Mechanical Breast stimulation (not recommended) Prostaglandins Oxytocin

Amniotic membrane stripping Works to cause spontaneous labor and decrease the need for induction. Shortens pregnancy by 3 days. Works to cause spontaneous labor and decrease the need for induction. Shortens pregnancy by 3 days. NNT = 8 to prevent one induction. NNT = 8 to prevent one induction. Sweep by placing finger(s) through the cervix and freeing the membranes from the uterus in a circular pattern. Sweep by placing finger(s) through the cervix and freeing the membranes from the uterus in a circular pattern. Begin at 38 weeks and do weekly. Begin at 38 weeks and do weekly. Hurts, can cause SROM, prolapse of cord, promotion of infection, bleeding. (Only the first and last are common.) Discuss with pt. first! Hurts, can cause SROM, prolapse of cord, promotion of infection, bleeding. (Only the first and last are common.) Discuss with pt. first!

Mechanical Foley # 16 with tip removed through the cervix. Inflate with 30 to 80 cc of water. Foley # 16 with tip removed through the cervix. Inflate with 30 to 80 cc of water. Retract so it rests against the internal os. Some attach to a liter of saline and suspend from the end of the bed. Not shown to improve success. Retract so it rests against the internal os. Some attach to a liter of saline and suspend from the end of the bed. Not shown to improve success. It works to improve Bishop score and decrease time to delivery. It works to improve Bishop score and decrease time to delivery. Can cause AROM, injury to placenta, pain. Can cause AROM, injury to placenta, pain.

Prostaglandins PGE1 – misoprostol. Optimal dose appears to be 25 micrograms q 3 to 6. PGE1 – misoprostol. Optimal dose appears to be 25 micrograms q 3 to works but seems to increase tachysystole more than works but seems to increase tachysystole more than microgram pill = $ microgram pill = $1. Works. Improves Bishop score and decreases time to delivery. Works. Improves Bishop score and decreases time to delivery. Associated with more FHT abnormalities and thick meconium than PGE2. Associated with more FHT abnormalities and thick meconium than PGE2.

Prostaglandins PGE2 – dinoprostone PGE2 – dinoprostone Prepidil – vaginal gel..5 mg q 6-8 hours to max of 3 doses. Prepidil – vaginal gel..5 mg q 6-8 hours to max of 3 doses. Cervidil – vaginal insert. 10 mg pladget inserted in vagina x 12 hours. Not approved for use > 1 x, but some do. Advantage is has a string and can pull if tachysystole and FHT problems. Cervidil – vaginal insert. 10 mg pladget inserted in vagina x 12 hours. Not approved for use > 1 x, but some do. Advantage is has a string and can pull if tachysystole and FHT problems. Both seem to be gentler than misoprostol. Both seem to be gentler than misoprostol. Both work. Cost > 100 x more than misopros. Both work. Cost > 100 x more than misopros.

Induction Misoprostol can be used q 3 to 6 hours for induction. Is effective but increase in tachysystole and thick meconium. Misoprostol can be used q 3 to 6 hours for induction. Is effective but increase in tachysystole and thick meconium. Pitocin Pitocin Effect after 5 minutes but steady state is reached in 40 minutes. Effect after 5 minutes but steady state is reached in 40 minutes. High dose vs. low dose: both work. High dose accomplishes delivery faster with more FHT problems but equal outcomes. High dose vs. low dose: both work. High dose accomplishes delivery faster with more FHT problems but equal outcomes.

SRHC – Smoky Hill Baseline FHT tracing. Is it reactive? What is variability? Baseline FHT tracing. Is it reactive? What is variability? Pitocin 10 units in 500 ml Normal Saline, 1 mu/3ml. (Triple concentration when reach 36 mu/min – makes for 1 mu/ml) Pitocin 10 units in 500 ml Normal Saline, 1 mu/3ml. (Triple concentration when reach 36 mu/min – makes for 1 mu/ml) Increase gradually to achieve 3 to 5 contractions over a 10 minute period. If the cervix is changing > 1 cm/hr, you do not need to increase the pit! Increase gradually to achieve 3 to 5 contractions over a 10 minute period. If the cervix is changing > 1 cm/hr, you do not need to increase the pit!

Tips for a successful induction Know your dates. Know your dates. Ripen the cervix. If not > 5-7, consider continued ripening. Ripen the cervix. If not > 5-7, consider continued ripening. Be patient. Do not consider the induction a failure until the pt. is through the latent phase (cx at least 4 cm) Be patient. Do not consider the induction a failure until the pt. is through the latent phase (cx at least 4 cm) AROM early if committed. AROM early if committed.