A 32-year-old woman, gravida 3 para 2, at 35 weeks gestation comes to the hospital due to frequent, painful uterine contractions. The patient started to have contractions an hour ago but has had no vaginal bleeding or leakage of fluid. She was incidentally diagnosed with a shortened cervix on routine anatomy ultrasound at 20 weeks gestation, for which she uses vaginal progesterone. The patient has no chronic medical conditions and has had no previous surgeries. Her prior pregnancies ended in term vaginal deliveries. Blood pressure is 120/70 mm Hg, and pulse is 80/min. Fetal heart tracing is normal. The tocodynamometer shows contractions every 6 minutes. A visibly dilated cervix is noted on speculum examination with no evidence of membrane rupture. On digital cervical examination, the cervix is 4 cm dilated and 90% effaced with the fetus at −3 station. Ultrasound examination reveals the fetus in vertex presentation. Which of the following is the best next step in management of this patient?

Question

A 32-year-old woman, gravida 3 para 2, at 35 weeks gestation comes to the hospital due to frequent, painful uterine contractions.  The patient started to have contractions an hour ago but has had no vaginal bleeding or leakage of fluid.  She was incidentally diagnosed with a shortened cervix on routine anatomy ultrasound at 20 weeks gestation, for which she uses vaginal progesterone.  The patient has no chronic medical conditions and has had no previous surgeries.  Her prior pregnancies ended in term vaginal deliveries.  Blood pressure is 120/70 mm Hg, and pulse is 80/min.  Fetal heart tracing is normal.  The tocodynamometer shows contractions every 6 minutes.  A visibly dilated cervix is noted on speculum examination with no evidence of membrane rupture.  On digital cervical examination, the cervix is 4 cm dilated and 90% effaced with the fetus at −3 station.  Ultrasound examination reveals the fetus in vertex presentation.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_da79_e0ad_bc81_9f12997b6cde_MD0003_00 This patient at 35 weeks gestation with regular, painful contractions causing cervical dilation is in preterm labor (ie, labor at <37 weeks gestation). Risk factors include short cervical length on transvaginal ultrasound (as in this patient), prior spontaneous preterm delivery, and multiple gestation. The management of preterm labor is largely dependent on gestational age. At ≥34 weeks gestation, tocolytic agents, such as indomethacin and nifedipine, are not recommended to temporarily halt preterm contractions and delay labor because the risks of indomethacin (eg, oligohydramnios, closure of the ductus arteriosus) and nifedipine (eg, maternal hypotension/tachycardia) outweigh the neonatal risks of preterm delivery (Choice E). Therefore, patients in preterm labor at ≥34 weeks gestation who have no contraindications to vaginal delivery (eg, placenta previa), receive expectant labor management. In addition, all patients in preterm labor are candidates for antenatal corticosteroids (eg, betamethasone) to decrease the risk of neonatal respiratory distress syndrome. Patients who are either group B Streptococcus positive or unknown require penicillin prophylaxis. (Choice A) Intramuscular 17-hydroxyprogesterone is used in patients with prior preterm delivery (not seen in this patient) to prevent recurrence. It is not used in the acute management of preterm labor. (Choice B) Emergency cervical cerclage is indicated for patients with acute cervical insufficiency (ie, painless cervical dilation at <24 weeks gestation). However, the procedure is inappropriate at >24 weeks gestation due to increased rates of failure and maternal cervical injury with increased gestational age. (Choice D) Magnesium sulfate is used for fetal neuroprotection (ie, cerebral palsy risk reduction) for fetuses at risk for preterm birth at <32 weeks gestation. It can also be used for seizure prophylaxis/treatment for patients with preeclampsia/eclampsia. It is not indicated in this patient at 35 weeks gestation with normal blood pressure. Educational objective: In patients with preterm labor at ≥34 weeks gestation, the risks of tocolysis outweigh the neonatal risks of preterm delivery. For this reason, expectant labor management is appropriate. All patients in preterm labor are candidates for antenatal corticosteroids, and those who are group B Streptococcus positive or unknown require penicillin prophylaxis. References: Acute tocolysis-a critical analysis of evidence-based data. (http://www.ncbi.nlm.nih.gov/pubmed/30655648) Short-term tocolytics for preterm delivery-current perspectives. (http://www.ncbi.nlm.nih.gov/pubmed/24707187)

A 32-Year-Old Woman, Gravida 3 Para 2, at 35 Weeks