INDUCTION OF LABOUR

2013

STATISTICS

• WHO recommendations for induction of labour, WHO 2011:

– In developed countries, IOL at term: 1 in 4 deliveries. – WHO Global Survey on Maternal and Perinatal Health:

IOL rate 9.6% of all deliveries. (373 health-care facilities in 24 countries and nearly 300 000 deliveries)

– Facilities in African countries had lower rates of induction of labour (lowest: Niger, 1.4%) compared with Asian and Latin American countries (highest: Sri Lanka, 35.5%).

460 – 370 BC. Hippocrates: Nipple stimulationHippocratic succussion

130 AD. Soranus of Ephesus: wrote about preterm delivery in women with small pelves

Enema with oil mixed with water and honeyArtificial rupture of membranesMidwife to dilate repeatedly the cervix with index finger

936-1013. Abu al-Qasim Khalaf ibn al-Abbas Al-Zahrawi (Albucasis):

Continues to use digital dilatationDevises instruments to produce dilatation

1510-1590. Ambroise Paré:Instruments to dilate the cervixOn man’s generation, and how to extract children out of their mother’s womb. Wechel, Paris 1573

• 1756, London convention:– Induce labour by preterm AROM in women with

small pelves• 1855. A sponge tent was invented: would

enlarge once inserted in cervix and dilate it

1891. Pinard: 100 cases of preterm IOL by

SpongesEnemasAROMVenesection (?...)

Around 1900: Bossi’s dilator

1894. Boissard balloon. Later: Voorhees metreurynter

• Ergot– Oldest mention: 600 BC– 17th century: used by German midwives– 18th century: description of use by French

midwives– 19th century: introduced in North America– abandoned due to high foetal mortality

• Quinine – Miscarriages observed with usage for fevers– 1885. Mullan: 4 grains (≈260 mg) of quinine

induce labour• Pituitary extract– 1909. William Blair Bell starts using it to

initiate/augment labour– 1928. Du Vigneaud and Abel concentrate the

pituitary hormone (i.e. oxytocin with vasopressin).

– 1949. Du Vigneaud isolates oxytocin from neurohypophysis

– 1953. He synthesizes oxytocin (first synthesis of a polypeptide hormone ever)

1955. Du Vigneaud is awarded the Nobel prize for chemistry. Oxytocin is used intravenously.

Prostaglandins

• 1930 . Raphael Kurzoak & Charles C. Lieb:– Fresh semen applied to strips of myometrium from

hysterectomy specimens made the muscle contract or sometimes relax

• Later, Goldblatt & von Euler:– Extracts from seminal vesicles and prostate glands were

causing contractions or relaxations in smooth muscles of various organs

• 1969. Chemists at Upjohn Pharmaceuticals & Elias J. Corey and coll. at Harvard:– Synthesize prostaglandins → Start the era of the use of

prostaglandins in labour induction

Pharmacologic methodsMozurkewich E L, Chilimigras J L, Berman D R, Perni U C, Romero V C, King V J and Keeton K L

Methods of induction of labour: a systematic review BMC Pregnancy Childbirth. 2011; 11: 84. (Univ. Michigan, Ann Arbor)

Intravaginal prostaglandins (PGE2 and PGF2a)Cervical PGE2OxytocinAmniotomyOxytocin with amniotomyVaginal MisoprostolOral MisoprostolBuccal or sublingual misoprostol

Mechanical methods

Laminaria tents Dilapan Foley catheters and other types of balloon

catheterMembrane sweeping

Complementary and Alternative Medicine Methods

Castor OilAcupunctureBreast StimulationIntercourseHomeopathic methodsHypnotic Relaxation

Investigational Methods

Extra-amniotic prostaglandinsIntravenous prostaglandinsOral prostaglandins (excluding misoprostol)MifepristoneOestrogensCorticosteroidsRelaxinHyaluronidaseIsosorbide Mononitrate

Breast stimulation

• Systematic review (6 studies, 719 subjects): BS vs placebo– No difference in CS rates , uterine hyperactivity– RR of not being in labour within 72 hrs: 0,67 (95% CI 0,6-

0,74)– Less post-partum haemorrhage (!) RR=0.16 (95% CI 0.03-

0.87)• Two studies (99 subjects): BS vs Oxytocin– No difference in uterine hyperactivity– Fewer women in labour within 72 hrs with BS (non-

significant)

Mechanical methods for induction of labour.

Cochrane Database Syst Rev. 2012 Mar 14.Jozwiak M, Bloemenkamp KW, Kelly AJ, Mol BW, Irion O, Boulvain M. GroeneHartHospital,Gouda,Netherlands

71 randomised controlled trials (total of 9722 women)

- Similar caesarean section rates as prostaglandins, for a lower risk of hyperstimulation. - Same number of women not delivered within 24 hours - However, more multiparas did not achieve vaginal delivery within 24 hours, when compared with vaginal PGE2. - Compared with oxytocin, mechanical methods reduce the risk of caesarean section.

Dilapan

Nitric oxide donors for cervical ripening and induction of labour.

Cochrane Database Syst Rev. 2011 Jun. 15 Kelly AJ, Munson C, Minden L. Royal Sussex County Hospital, Brighton

10 trials (including a total of 1889 women)

- Compared NO donors to placebo, vaginal prostaglandin E2, intracervical PGE2 and vaginal misoprostol- There is no difference between any of the prespecified outcomes, with the exception of an increase in maternal side effects.

Mifepristone for induction of labourCochrane Database Syst Rev. 2009 Jul 8. Hapangama D, Neilson JP Perinatal and Reproductive Medicine, The University of Liverpool

Ten trials (1108 women)

Compared to placebo:- More likely to be in labour or to have a favourable cervix at 48 hours (RR 2.41, 95% CI 1.70 to 3.42); effect persisted at 96 hrs.- Less likely to need augmentation with oxytocin (RR 0.80, 95% CI 0.66 to 0.97).- Less likely to undergo caesarean section (RR 0.74, 95% CI 0.60 to 0.92) but more likely to have an instrumental delivery (RR 1.43, 95% CI 1.04 to 1.96).- Less likely to undergo a caesarean section from failure to induce labour (RR 0.40, 95% CI 0.20 to 0.80)- Abnormal FHR patterns more common (RR1.85, 95% CI1.17 to 2.93) but no difference in neonatal outcome

Methods of term labour induction for women with a previous caesarean section

Cochrane Database Syst Rev. 2013 Mar 28 Jozwiak M, Dodd JM LUMC, Leiden, Netherlands

Two studies (involving a total of 80 women)Used different methods and thus, meta-analysis was not appropriate

2.5 mg vaginal PGE2 inserts vs oxytocin (Taylor and coll). No signif. difference in:caesarean section, instrumental vaginal deliveries, epidural analgesia, Apgar score, perinatal deathOne uterine rupture in the PG group (after oxytocin)

Misoprostol vs oxytocin (Wing and coll): 2 uterine ruptures in Misoprostol groupInsufficient information…