7.1 Drugs used in obstetrics
These preparations are specialist use only.
Dinoprostone (vaginal gel, vaginal tablets) is the drug of choice for induction of labour. The two preparations are not bioequivalent, the usual dose of gel being 1 - 2mg, whereas that of the tablets is 3mg.
Dinoprostone 10mg vaginal delivery system (Propess®) is a pessary formulation available for initiation of cervical ripening in patients at term (from 38th week of gestation). The pessary formulation releases approximately 10mg dinoprostone over 24 hours and can remain in place for up to 24 hours where necessary.
Gemeprost (pessaries) is used to soften and dilate the cervix before induction of abortion. In order to ensure that the patient receives maximum benefit from the drug, it is essential that the pessary is inserted as near as possible to 3 hours before the operative procedure is due to be carried out. Gemeprost is also used in conjunction with mifepristone (see special indications).
Oxytocin (injection) is given by slow intravenous infusion for induction and augmentation of labour. It may also be used in the treatment of post-partum haemorrhage. Guidelines for the use of this product are included in the Aberdeen Maternity Hospital Labour Ward protocol/Dr. Gray's labour ward protocol.
Syntometrine® (injection) is a combination of oxytocin (5 units) and ergometrine maleate (500 micrograms) in 1mL. It is given by intramuscular injection for the routine management of the third stage of labour. It is also the drug of choice in the management and prevention of post-partum haemorrhage, and for the control of bleeding due to incomplete abortion. Its use is contra-indicated in patients with high blood pressure/pre-eclampsia. It is used in accordance with the guidelines included in the Aberdeen Maternity Hospital labour ward protocol.
Ergometrine maleate (injection) is used for the management of post-partum haemorrhage.
Mifepristone (tablets) is used in conjunction with gemeprost pessaries or misoprostol (200microgram tablets) [unlicensed indication] for the medical termination of pregnancy. It is also used to soften and dilate the cervix before mechanical cervical dilation for termination of pregnancy.
Misoprostol (100microgram tablets) [unlicensed product] is available for restricted use for the induction of labour for women who have a late intrauterine foetal death (IUFD: after 24 completed weeks of pregnancy) of a singleton foetus. Restriction: Hospital use only, limited to maternity units and prescribed by Obstetricians; prescribing as per RCOG guideline [Green-top Guideline No.55] Late Intrauterine Fetal Death and Stillbirth guidance/NICE CG 70 Induction of labour. As misoprostol is not licensed for use for labour induction in foetal death in utero in the UK, informed consent should be obtained and documented.
Carboprost (injection) is used to treat post-partum haemorrhage in patients who do not respond to oxytocin.
Atosiban (injection) may be used to delay imminent birth in uncomplicated pre-term labour. See Aberdeen Maternity Hospital Labour Ward guidelines.