Tocolysis for Women With Early Spontaneous Preterm Labor and Advanced Cervical Dilation

Abstract

Objective To characterize tocolytic use and examine perinatal outcomes among women presenting very preterm with spontaneous labor and cervical dilation ≥4 cm. Methods This was a retrospective cohort study. Data from January 2000 to June 2011 in a single healthcare system were reviewed. Women with singleton, non-anomalous fetuses, and preterm labor with intact membranes between 23.0–32.0 weeks gestation who had cervical dilation ≥4 cm and <8 cm at admission were included. Women receiving one or more tocolytics (magnesium sulfate, indomethacin, or nifedipine) were compared to those who did not receive tocolysis. The primary outcome was composite major neonatal morbidity. Results Two hundred ninety seven women were included; 233 (78.5%) received at least one tocolytic. Women receiving tocolysis were slightly less dilated (median 5 vs. 6 cm, p<0.001) at presentation, and were more likely to receive at least a partial course of corticosteroids (88.4% vs. 56.3%, p<0.001). Initial composite severe neonatal morbidity rates were similar (41.6% vs. 43.8%, p=0.761) regardless of tocolytic administration. Those receiving tocolysis were significantly more likely to be pregnant at least 48 hours after admission (23.6% vs. 7.8%, p=0.005), but a similar proportion delivered within 7 days of admission (94.8% vs. 95.3%, p>0.99), and delivery gestational ages were similar (28.9 vs. 29.2 weeks, p=0.408). The incidence of chorioamnionitis and postpartum endometritis were similar between groups. Conclusion The majority of women presenting very preterm with advanced cervical dilation received tocolysis. Although tocolysis administration increased the likelihood of achieving at least 48 hours of latency, initial neonatal outcomes were similar.

Tocolysis for inhibiting preterm birth in extremely preterm birth, multiple gestations and in growth-restricted fetuses: a systematic review and meta-analysis

“…The risk of bias assessment for individual studies resulted with two RCTs [ 21 , 22 ] rated with unclear risk and one RCT [ 23 ] rated with high risk. For the non-RCTs, based on RoBANS assessment criteria, two retrospective studies [ 26 , 27 ] were rated with unclear risk and the other two retrospective studies [ 24 , 25 ] were rated with high risk of bias. The summary of risk of bias within studies is presented in an additional file (see Additional file 3 ).…”

“…The identified non-RCTs evaluated tocolytic treatment versus to treatment, and two of the studies [ 24 , 27 ] included cerclage with tocolysis treatment. Of the four studies, three studies [ 24 , 25 , 27 ] included information of 471 women who were at 14 to 23.9 weeks of pregnancy and one study [ 26 ] included only the information of 138 neonates of whom the mothers were at less than 29 weeks of pregnancy (Table 3 ). In regard to the types of tocolytics, three of the studies [ 24 , 26 , 27 ] evaluated indomethacin and one of the studies [ 25 ] evaluated any tocolytic medication (e.g.…”

“… Indomethancin plus some with cerclage No treatment plus some with cerclage Prolongation of pregnancy >28, 32, or 35 weeks (50 mg orally, followed by 25 mg orally every 6 h for a maximum of 48 h) Perinatal death Birth weight >1500 grams Cape 2010 [ 26 ] USA Retrospective cohort (2003–2008) a 138 neonates ( n = 69 vs. n = 69) All women less than 29 weeks of gestation with threaten with premature rupture of membranes. Indomethancin No treatment Neonatal outcomes only including intraventricular hemorrhage, necrotizing enterocolitis, patent ductus arteriosus, and spontaneous intestinal perforations Manuck 2012 [ 25 ] USA Retrospective cohort (January 2000 – June 2011) 148 ( n = 84 vs. n = 64) Women with a singleton non-anomalous fetus with spontaneous preterm labour and intact membranes, between 20–23.9 week of gestation, and with cervical dilation ≥ 1 cm and effaced > 50 %. Tocolytic medication No treatment Prolongation of pregnancy >7 days (Database record of tocolytic treatment used i.e.…”

Effectiveness and Safety of Isoxsuprine Hydrochloride as Tocolytic Agent in Arresting Active/Threatened Preterm Labor and Its Role in Maintenance Tocolysis: A Prospective, Open-Label Study

“…Treatment with tocolytics has been associated with successful pregnancy prolongation for 48 hours, permitting administration of antenatal corticosteroids, reducing neonatal morbidity and mortality. 27 The present study evaluated effectiveness and safety of isoxsuprine hydrochloride administered acutely (IV administration followed by IM injection) and as maintenance therapy (oral isoxsuprine hydrochloride capsule-40 mg) in arresting preterm labor, and its effect on maternal and neonatal outcomes.…”

Success rate in preterm uterine contraction inhibition with tocolytic agents in a tertiary care center

“…Likewise, the study at Siriraj Hospital, Bangkok, Thailand, revealed that the success rate in threatened preterm labor inhibition for 12 hours with nifedipine was about 80% 11. However, in cases of women with advanced cervical dilatation (4–8 cm) who received one or more tocolytics (magnesium sulfate, indomethacin, or nifedipine), only 23% could prolong pregnancy at least 48 hours after admission 12. Similarly, in cases of women with the diagnosis of preterm labor based on the presence of uterine contraction with documented cervical change, success rate by nifedipine was 70% 13.…”