Sublingual nitroglycerine as a tocolytic in external cephalic version: a comparative study.
OBJECTIVE
To study the effect of sublingual nitroglycerine as a tocolytic on the success rate of external cephalic version (ECV) in nulliparous and parous women.


METHODS
A retrospective case-controlled study of all ECV cases from February 1996 to February 2000 in a single centre. The rates of successful ECV were compared between women who had their ECV before February 1998 (control group), those who had their ECV after February 1998 and received 0.8 mg sublingual nitroglycerine spray as a tocolytic agent, and those who had their ECV after February 1998 and received no tocolytic agents. Nulliparous and parous women were studied separately. Data were collected for parity, gestational age, maternal age, placental localization, and side effects. Chi-square and Kruskal-Wallis tests were performed for statistical comparison.


RESULTS
Of 150 women who had their ECV after February 1998, 120 (80%) received sublingual nitroglycerine (group 1: cases using 0.8 mg sublingual nitroglycerine spray as a tocolytic agent) and were compared to the 30 patients who did not receive sublingual nitroglycerine or other tocolytics after February 1998 (group 2) and to 137 patients who had their ECV before February 1998 (control group). Of the women who received sublingual nitroglycerine, 5 (4%) had hypotension and 7 (6%) had headaches and/or nausea. The rate of successful ECV was 27% in group 1 versus 30% in group 2 (p = 0.86) versus 28% in the control group (p = 0.88) for nulliparous patients, and 67% versus 80% (p = 0.30) versus 51% (p = 0.09) respectively for parous women. However, the success rate was increased overall in parous women after the introduction of nitroglycerine as a tocolytic for ECV in February 1998 (71% vs. 51%, p = 0.02).


CONCLUSIONS
Although the success rate of ECV has increased in recent years, the use of sublingual nitroglycerine as a tocolytic was not associated with this higher success rate. A randomized, controlled trial is needed.
Bujold
Emmanuel
E
Department of Obstetrics and Gynecology, Centre Hospitalier de l'Université de Montréal, CHUM Hôpital-St-Luc, Montréal, QC, Canada.
Sergerie
Martin
M
Masse
André
A
Verschelden
Guy
G
Bédard
Marie-Josée
MJ
Dubé
Johanne
J
D000286:Administration, Sublingual; D000293:Adolescent; D000328:Adult; D001946:Breech Presentation; D016022:Case-Control Studies; D036861:Delivery, Obstetric; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008875:Middle Aged; D005996:Nitroglycerin / Q000008:administration & dosage / Q000627:therapeutic use*; D010298:Parity; D011247:Pregnancy; D012189:Retrospective Studies; D015149:Tocolytic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D014590:Uterine Contraction / Q000187:drug effects; D014710:Version, Fetal
D015149:Tocolytic Agents; D005996:Nitroglycerin