Oxytocin/Ergometrine Maleate

To compare intramuscular oxytocin, Syntometrine® and carbetocin for prevention of postpartum haemorrhage after vaginal birth.

Randomised double‐blinded clinical trial.

Six hospitals in England.

A total of 5929 normotensive women having a singleton vaginal birth.

Randomisation when birth was imminent.

Primary: use of additional uterotonic agents. Secondary: weighed blood loss, transfusion, manual removal of placenta, adverse effects, quality of life.

Participants receiving additional uterotonics: 368 (19.5%) oxytocin, 298 (15.6%) Syntometrine and 364 (19.1%) carbetocin. When pairwise comparisons were made: women receiving carbetocin were significantly more likely to receive additional uterotonics than those receiving Syntometrine (odds ratio [OR] 1.28, 95% CI 1.08–1.51, P = 0.004); the difference between carbetocin and oxytocin was non‐significant (P = 0.78); Participants receiving Syntometrine were significantly less likely to receive additional uterotonics than those receiving oxytocin (OR 0.75, 95% CI 0.65–0.91, P = 0.002). Non‐inferiority between carbetocin and Syntometrine was not shown. Use of Syntometrine reduced non‐drug PPH treatments compared with oxytocin (OR 0.64, 95% CI 0.42–0.97) but not carbetocin (P = 0.64). Rates of PPH and blood transfusion were not different. Syntometrine was associated with an increase in maternal adverse effects and reduced ability of the mother to bond with her baby.

Non‐inferiority of carbetocin to Syntometrine was not shown. Carbetocin is not significantly different to oxytocin for use of additional uterotonics. Use of Syntometrine reduced use of additional uterotonics and need for non‐drug PPH treatments compared with oxytocin. Increased maternal adverse effects are a disadvantage of Syntometrine.

IM carbetocin does not reduce additional uterotonic use compared with IM Syntometrine or oxytocin.

Simple and sensitive second derivative and synchronous spectrofluorimetric methods have been developed and validated for the quantitative determination of oxytocin and ergometrine maleate in their pure and combined dosage forms. The methods are based on the derivatization reaction of oxytocin with fluorescamine reagent, which yielded a highly fluorescent compound measured at 486 nm after excitation at 390 nm. Ergometrine was directly measured in combination with oxytocin, since it exhibits native fluorescence at 421 nm after excitation at 300 nm. Quantitation of oxytocin in presence of ergometrine was also successful at 482 and 477 nm using second derivative and synchronous spectrofluorimetry, respectively. Different experimental parameters were studied and optimized. The relative fluorescence intensity versus concentration plot was rectilinear over the range of 0.04-0.75 and 5-100 ng/mL for oxytocin and ergometrine, respectively. The methods were successfully applied for the determination of both drugs in their prepared combined ampoules. The methods were validated and compared with the reference chromatographic method; they revealed good accuracy and reproducible results. The proposed methods showed high accuracy and sensitivity, with no requirement of multiple steps or previous chemical separation.