[Use of calcium channel blockers (CCB) for tocolysis in France and abroad]. / Utilisation des inhibiteurs des canaux calciques (ICC) en tocolyse en France et à l'étranger.

OBJECTIVES: Calcium channel blockers (CCB) are routinely off-label used for tocolysis. The purpose of this study is to establish an inventory of the use of CCB for tocolysis in France and abroad. MATERIALS AND METHODS: Four complementary approaches were performed: (i) a literature review of clinical practice and guidelines of scientific societies; (ii) a national declarative practice survey among French tertiary care centers; (iii) a regional declarative practice survey among all maternities of the Midi-Pyrénées Perinatal Network (MATERMIP); (iv) an evaluation of outpatient tocolysis prescription, analyzing the departmental database EFEMERIS in order to examine drug prescribing during pregnancy. RESULTS: CCB appear to be currently used as first-line, initial tocolysis, in the majority of French maternity hospitals (82.5% of tertiary care centers). Oral Nifedipine is the predominant regimen (86%). CCB utilization rates appear higher than those reported in 2005 in the EVAPRIMA study. Beta-agonists appear rarely prescribed in 1st line (poor maternal tolerance) and even abandoned by many institutions (75% of tertiary care centers). Using a maintenance tocolysis (usually by long-acting CCB) seems to vary depending on the hospitals. It would be prescribed in more than 50% of cases (and probably more in type 1 or 2 hospitals), despite the lack of demonstrated benefit. Furthermore, we can estimate that about 1.5 to 2% of outpatient pregnant women receive a prescription of Nifedipine LP in France. CONCLUSION: CCB (especially Nifedipine) are widely used in the treatment of threatened preterm labor in France, regardless of the type of hospital. The terms of off-label prescribing are not met.

Single versus combination tocolytic regimen in the prevention of preterm births in women: a prospective cohort study.

OBJECTIVE: Our objective is to compare the efficacy of combination regimen (salbutamol and nifedipine) against single regimen (nifedipine alone) in preventing preterm births among women with preterm labor. RESULTS: A total of 76 women with gestational age (GA) ranging from 24+0 to 35+6 weeks, who sought treatment for preterm labor with or without cervical dilatation, were recruited for the prospective cohort study. Of these, 38 (50%) had single tocolytic regimen and 38 (50%) had combination tocolytic regimen. The mean GAs at admission were similar for both groups at 31 weeks (±2.93) for Group 1 and 30.9 weeks (±2.88) for Group 2 (P=0.873). The mean GAs at delivery were 37.8 weeks (±1.98) for the single regimen and 36.2 weeks (±3.26) for the combined regimen (P=0.011). The mean tocolytic to delivery interval for the single regimen was longer at 6.74 weeks (±3.13) as compared with 5.21 weeks (±3.61) for the combination regimen (P<0.05). Those on the combination regimen complained of more adverse effects (P<0.001). CONCLUSION: Our study results suggested that the use of nifedipine as a single tocolytic regimen is as effective as the combination regimen in the delay of preterm births and has much less side effects. Hence, we recommend the sole use of nifedipine for the management of preterm labor.