Induction of labour is the planned treatment that stimulates childbirth and delivery prior to its spontaneous onset. Inducing labour can be accomplished with pharmaceutical or non-pharmaceutical methods. Every year, 1 in 5 labours are induced in the UK.
Most women go into labour naturally (spontaneously) by the time they’re 42 weeks pregnant.
Induction is offered to all women who don’t go into labour naturally by 42 weeks, as there’s a higher risk of stillbirth or problems for the baby if pregnancy exceeds 42 weeks.
Other indications for induction include circumstances when there is increased risk to mother or baby, for example high blood pressure, pre-eclampsia or the baby isn’t growing. Once active labour is established, maternal and foetal monitoring should be carried out
Spontaneous rupture of membranes more than 24 hours before labour starts, has an increased risk of infection and is an indication for induction.
There are a number of absolute contraindications to induction including placenta praevia and severe foetal compromise.
It is therefore usually a medical decision to deal with a specific problem. There is however an argument in favour of inducing all women at term or shortly after.
Induction of labour for improving birth outcomes for women at or beyond term Philippa Middleton, Emily Shepherd, Caroline A Crowther
First published: 9 May 2018 Editorial Group: Cochrane Pregnancy and Childbirth Group
To assess the effects of a policy of labour induction at or beyond term compared with a policy of awaiting spontaneous labour, or until an indication for birth induction of labour is identified, on pregnancy outcomes for infant and mother.
A policy of labour induction at or beyond term compared with expectant management is associated with fewer perinatal deaths and fewer caesarean sections; but more operative vaginal births. NICU admissions were lower and fewer babies had low Apgar scores with induction. No important differences were seen for most of the other maternal and infant outcomes.

Methods of Induction
Methods of inducing labour include both pharmacological medication and mechanical or physical approaches.
• Prostaglandin E2 is the most studied compound and with most evidence behind it. A range of different dosage forms are available with a variety of routes possible. Vaginal PGE2 should not be used if there are specific clinical reasons for not using it (in particular the risk of uterine hyper-stimulation).
• Intravenous administration of synthetic oxytocin preparations.
• “Membrane sweep”, also known as membrane stripping, or “stretch and sweep” during an internal examination, the practitioner moves their finger within the cervix to stimulate and/or separate the membranes around the baby from the cervix. This causes a release of prostaglandins which can help to kick-start labour.
• Artificial rupture of the membranes (AROM or ARM) (“breaking the waters”) which is usually done immediately following a membrane sweep.
• Cervical balloons catheters and laminaria tents are not used routinely for induction of labour.

The most recent reviews on the subject of induction and its effect on Caesarean section indicate that there is no increase with induction and in fact there can be a reduction.
Ekaterina Mishanina et al., “Use of labour induction and risk of caesarean delivery: a systematic review and meta-analysis”, April 2014, Canadian Medical Association Journal
Our meta-analysis showed that the risk of caesarean delivery following labour induction was significantly lower than the risk associated with expectant management. This finding supports evidence from systematic reviews but is contrary to prevalent beliefs and information from consumer organizations, guidelines and textbooks. Labour induction was associated with benefits for the fetus and no increased risk of maternal death.

How effective is amniotomy as a means of induction of labour? 2010, 179 (3):381-3 Ir J Med Sci
In total, 26,670 women delivered in the National Maternity Hospital during the study period. Of these 4,928 women required induction of labour and 72.8% of these (n = 3,586) underwent amniotomy only for induction of labour. Spontaneous labour occurred in 90.1% of the women who underwent amniotomy within 24 h. Oxytocin as an induction agent was employed in 9.8% of cases. Overall, 80.5% of the women had a spontaneous delivery, 7.3% had a ventouse delivery, 4.3% had a forceps delivery, and 7.9% underwent a caesarean section. CONCLUSIONS: Amniotomy is a simple, safe and effective method of induction of labour.

If there is a medical indication to induce labour then the decision had been taken to deliver that patient within 24 hours. Induction is an active process and should not be dependent on suitability unless the alternative is immediate caesarean section.

1. Allahyar, J. & Galan, H. “Premature Rupture of the Membranes.”American College of Obstetrics and Gynecologists.
2. Mishanina, E; Rogozinska, E; Thatthi, T; Uddin-Khan, R; Khan, KS; Meads, C (Jun 10, 2014). “Use of labour induction and risk of caesarean delivery: a systematic review and meta-analysis”. CMAJ : Canadian Medical Association Journal. 186 (9): 665–73.
3. Li XM, Wan J, Xu CF, Zhang Y, Fang L, Shi ZJ, Li K (March 2004). “Misoprostol in labor induction of term pregnancy: a meta-analysis”. Chin Med J (Engl). 117 (3): 449–52.
4. Budden, A; Chen, LJ; Henry, A (Oct 9, 2014). “High-dose versus low-dose oxytocin infusion regimens for induction of labour at term”. The Cochrane Database of Systematic Reviews. 10: CD009701.
5. Clark K, Ji H, Feltovich H, Janowski J, Carroll C, Chien EK (May 2006). “Mifepristone-induced cervical ripening: structural, biomechanical, and molecular events”. Am. J. Obstet. Gynecol. 194 (5): 1391–8.
6. Kelly AJ, Kavanagh J, Thomas J (2001). “Relaxin for cervical ripening and induction of labor”. Cochrane Database Syst Rev (2): CD003103.
7. Guinn, D. A.; Davies, J. K.; Jones, R. O.; Sullivan, L.; Wolf, D. (2004). “Labour induction in women with an unfavourable Bishop score: Randomized controlled trial of intrauterine Foley catheter with concurrent oxytocin infusion versus Foley catheter with extra-amniotic saline infusion with concurrent oxytocin infusion”. American Journal of Obstetrics and Gynecology. 191 (1): 225–229
8. ACOG Committee on Practice Bulletins (2009). “ACOG Practice Bulletin No. 107: Induction of Labor”. Obstetrics & Gynecology. 114 (2, Part 1): 386–397.
9. Ekaterina Mishanina et al., “Use of labour induction and risk of cesarean delivery: a systematic review and meta-analysis”, April 2014, Canadian Medical Association Journal,
10. Heinberg EM, Wood RA, Chambers RB. Elective induction of labor in multiparous women. Does it increase the risk of cesarean section? 2002. J Reprod Med. 47(5):399–403.
11. Tim A. Bruckner et al, Increased neonatal mortality among normal-weight births beyond 41 weeks of gestation in California, October 2008, American Journal of Obstetrics and Gynecology, [2]
12. Caughey, AB; Sundaram, V; Kaimal, AJ; Gienger, A; Cheng, YW; McDonald, KM; Shaffer, BL; Owens, DK; Bravata, DM (Aug 18, 2009). “Systematic review: elective induction of labor versus expectant management of pregnancy”. Annals of Internal Medicine. 151 (4): 252–63, W53–63.
13. Caughey, AB; Sundaram, V; Kaimal, AJ; Gienger, A; Cheng, YW; McDonald, KM; Shaffer, BL; Owens, DK; Bravata, DM (Aug 18, 2009). “Systematic review: elective induction of labor versus expectant management of pregnancy”. Annals of Internal Medicine. 151 (4): 252–63,
14. National Institute for Health and Clinical Excellence, “CG70 Induction of labour: NICE guideline”,
15. Vernon, David, Having a Great Birth in Australia, Australian College of Midwives, 2005,
16. Roberts Christine L; Tracy Sally; Peat Brian (2000). “Rates for obstetric intervention among private and public patients in Australia: population based descriptive study”. British Medical Journal. 321: 140.
17. Yeast John D (1999). “Induction of labor and the relationship to caesarean delivery: A review of 7001 consecutive inductions”. American Journal of Obstetrics and Gynecology
18. Simpson Kathleen R.; Thorman Kathleen E. (2005). “Obstetric ‘Conveniences’ Elective Induction of Labor, Cesarean Birth on Demand, and Other Potentially Unnecessary Interventions”. Journal of Perinatal and Neonatal Nursing. 19 (2): 134–44.
19. Caughey AB, Nicholson JM, Cheng YW, Lyell DJ, Washington E (2006). “Induction of labor and caesarean delivery by gestational age”. Am Journal of Obstetrics and Gynecology. 195: 700–5.
20. J Caughey A. (8 May 2013). “Induction of labour: does it increase the risk of cesarean delivery?”. BJOG. 121 (6): 658–661.
21. The Institute for Safe Medication Practices Results Of ISMP Survey On High-Alert Medications: Differences Between Nursing, Pharmacy, And Risk/Quality/Safety Perspectives
22. Gülmezoglu AM, Crowther CA, Middleton P, et al Induction of labour for improving birth outcomes for women at or beyond term. Cochrane Database Syst Rev 2012;(6):CD004945.
23. Wennerholm UB, Hagberg H, Brorsson B, et al Induction of labor versus expectant management for post-date pregnancy: Is there sufficient evidence for a change in clinical practice? Acta Obstet Gynecol Scand 2009;88:6–17.
24. Wood S, Cooper S, Ross S. Does induction of labour increase the risk of caesarean section? A systematic review and meta-analysis of trials in women with intact membranes. BJOG 2014;121:674–85.
25. Willacy H Labour — active management and induction.; 2009.
26. Caesarean section [clinical guideline 132]. London (UK): National Institute for Health and Clinical Excellence; 2004.
27. Warren R, Arulkumaran S Best practice in labour and delivery. Cambridge (UK): Cambridge University Press; 2009

Premature Rupture of Membranes

Premature rupture of membranes (PROM), is defined as rupture of membranes (breakage of the amniotic sac), commonly called breaking of the mother’s waters, more than 1 hour before the onset of labour. The sac (consisting of 2 membranes, the chorion and amnion) contains amniotic fluid, which surrounds and protects the fetus in the uterus (womb). After rupture, the amniotic fluid leaks out of the uterus, through the vagina. The foetal membranes serve as a barrier to ascending infection. Once the membranes rupture, both the mother and fetus are at risk of infection and of other complications.
Women with PROM usually experience a painless gush of fluid leaking out from the vagina, but sometimes a slow steady leakage occurs instead.
Premature rupture of membranes (PROM) refers to a patient who is beyond 37 weeks’ gestation and has presented with rupture of membranes (ROM) prior to the onset of labour. Preterm premature rupture of membranes (PPROM) is ROM prior to 37 weeks’ gestation. Prolonged ROM is any ROM that persists for more than 24 hours prior to the onset of labour.
Eighty-five percent of neonatal morbidity and mortality is a result of prematurity. PPROM is associated with 30-40% of preterm deliveries and is the leading identifiable cause of preterm delivery. PPROM complicates 3% of all pregnancies and occurs in approximately 150,000 pregnancies yearly in the United States
Despite the common TV image of ROM occurring in every pregnancy, PROM occurs in approximately 10% of pregnancies. Patients with PROM present with leakage of fluid, vaginal discharge, vaginal bleeding, and pelvic pressure, but they are not having contractions. Most patients (90%) enter spontaneous labour within 24 hours when they experience ROM at term. The major question regarding management of these patients is whether to allow them to enter labour spontaneously or to induce labour. The management of these patients depends on a number of factors including patient’s wishes, however, the major maternal risk at this stage is intrauterine infection. The risk of intrauterine infection increases with the duration of ROM. Evidence supports the idea that induction of labour, as opposed to expectant management, decreases the risks.
Premature preterm rupture of membranes (PPROM) occurring from 24-37 weeks’ gestation is far more difficult to manage than premature rupture of membranes (PROM) at term. Prematurity is the principal risk to the fetus, while infection morbidity and its complications are the primary maternal risks. The initial evaluation of premature preterm rupture of membranes (PPROM) should include a sterile speculum examination to document ROM. Cervical cultures including Chlamydia trachomatis and Neisseria gonorrhoeae should be obtained. ROM diagnosis needs to be confirmed. Digital vaginal examinations should be avoided. Ultrasonography should be performed to confirm gestational age,
Maternal vital signs should be documented as well as continuous foetal monitoring initially to establish foetal status. Once the decision to manage a patient expectantly has been made, the institution of broad-spectrum antibiotics should be considered. Multiple trials have examined the advantages and disadvantages of using antibiotics and the choice of antibiotics. In most studies, use of antibiotics has been associated with prolongation of pregnancy and reduction in infant and maternal morbidity. However, a few studies have reported increased neonatal morbidity.
The RCOG recommends
Antenatal prophylactic antibiotics for women with PPROM
Offer women with PPROM oral erythromycin 250 mg 4 times a day for a maximum of 10 days or until the woman is in established labour (whichever is sooner).
For women with PPROM who cannot tolerate erythromycin or in whom erythromycin is contraindicated, consider oral penicillin for a maximum of 10 days or until the woman is in established labour (whichever is sooner).
Do not offer women with PPROM co amoxiclav as prophylaxis for intrauterine infection.

The use of corticosteroids to accelerate lung maturity should be considered in all patients with PPROM with a risk of infant prematurity from 24-34 weeks’ gestation. A single course of corticosteroids is recommended for pregnant women 24-34 weeks’ gestation who are at risk of preterm delivery within 7 days.

Several techniques have been developed in an attempt to artificially reseal the foetal membranes and prevent leakage of amniotic fluid including, among others, intra-amniotic injection of platelets and cryoprecipitate (amnio-patch), sealing the cervical canal, and laser coagulation. However, there is as yet no effective and safe technique to achieve this goal.

1. Mercer BM, Arheart KL. Antimicrobial therapy in expectant management of preterm premature rupture of the membranes. Lancet. 1995;346:1271–9.
2. Hannah ME, Ohlsson A, Farine D, Hewson SA, Hodnett ED, Myhr TL, et al. Induction of labor compared with expectant management for prelabor rupture of the membranes at term. N Engl J Med. 1996;334:1005–10.
3. Schucker JL, Mercer BM. Midtrimester premature rupture of the membranes. Semin Perinatol. 1996;20:389–400.
4. American College of Obstetricians and Gynecologists. Premature rupture of membranes. Clinical management guidelines for obstetrician-gynecologists. ACOG practice bulletin no. 1. Int J Gynaecol Obstet. 1998;63:75–84.
5. Mercer BM. Preterm premature rupture of the membranes. Obstet Gynecol. 2003;101:178–93.
6. Smith CV, Greenspoon J, Phelan JP, Platt LD. Clinical utility of the nonstress test in the conservative management of women with preterm spontaneous premature rupture of the membranes. J Reprod Med. 1987;32:1–4.
7. Cox SM, Leveno KJ. Intentional delivery versus expectant management with preterm ruptured membranes at 30–34 weeks’ gestation. Obstet Gynecol. 1995;86:875–9.
8. ACOG Committee on Practice Bulletins-Obstetrics, authors. Clinical management guidelines for obstetrician-gynecologists. (ACOG Practice Bulletin No. 80: premature rupture of membranes).Obstet Gynecol. 2007;109:1007–1019.
9. Spinillo A, Montanari L, Sanpaolo P, et al. Fetal growth and infant neuro-developmental outcome after preterm premature rupture of membranes. Obstet Gynecol. 2004;103:1286–1293
10. Healy AJ, Veille JC, Sciscione A, et al. The timing of elective delivery in preterm premature rupture of the membranes: a survey of members of the Society of Maternal-Fetal Medicine. Am J Obstet Gynecol. 2004;190:1479–1481.
11. Lee SE, Park JS, Norwitz ER, et al. Measurement of placental alpha-microglobulin-1 in cervicovaginal discharge to diagnose rupture of membranes. Obstet Gynecol. 2007;109:634–640
12. Mercer BM. Preterm premature rupture of the membranes: current approaches to evaluation and management. Obstet Gynecol Clin North Am. 2005;32:411–428.
13. Gold RB, Goyert GL, Schwartz DB, et al. Conservative management of second-trimester postamniocentesis fluid leakage. Obstet Gynecol. 1989;74:745–747.
14. Lewi L, Van Schoubroeck D, Van Ranst M, et al. Successful patching of iatrogenic rupture of the fetal membranes. Placenta. 2004;25:352–356.
15. Bonanno C, Fuchs K, Wapner RJ. Single versus repeat courses of antenatal steroids to improve neonatal outcomes: risks and benefits. Obstet Gynecol Surv. 2007;62:261–271.
16. Kenyon S, Boulvain M, Neilson J. Antibiotics for preterm rupture of the membranes: a systematic review. Obstet Gynecol. 2004;104:1051–1057.

Normal Pregnancy

The first lecture that I presented at McMaster University I gave the title “What is normal?” This was about research and laboratory data. A paper had been published by an English university which I disagreed with. The paper was on infertility in patients with “normal Prolactin levels”. In this study the patients had blood samples taken on one occasion in a morning. Prolactin has a diurnal variation (the level changes from morning to night). We had demonstrated marked variations in the same patient at different times of the day, with levels up to five times higher in the evening. The laboratory reports a level against a normal value. However it is never stated if this is an internationally recognised normal, normal for the equipment used, normal for the assay established by that laboratory or normal for that patient. All laboratories have reference levels for healthy men and women but although it is known that levels for most routine laboratory tests change during pregnancy, many laboratories do not show ranges for pregnant women.
There is no such thing as a normal pregnancy – every mother and baby is unique. There are however some common features.
Symptoms of pregnancy
A missed period is usually the first signal of pregnancy, although women with irregular periods may not recognize this. During this time, many women experience a need to urinate frequently, extreme fatigue, nausea and/or vomiting, and increased breast tenderness. Most over-the-counter pregnancy tests are sensitive 9-12 days after conception. During early pregnancy, most women experience an increased appetite.
Weight gain during pregnancy
Weight gain during pregnancy consists of the products of conception (fetus, placenta, amniotic fluid) increase of maternal organs and tissues (uterus, breasts, blood, extracellular fluid, maternal fat stores). The rate of weight gain varies with the trimester. Although weight should be gained throughout pregnancy, it is most critical in the second trimester. The appropriate gestational weight gain depends upon the pre-pregnancy Body Mass Index (BMI). The Institute of Medicine’s 2009 pregnancy weight gain recommendation guidelines for singleton pregnancies are
Underweight (BMI less than 18.5) – 28-40 lbs
Normal weight (BMI of 18.5-24.9) – 25-35 lbs
Overweight (BMI of 25-29.9) – 15-25 lbs
Obese (BMI that exceeds 30) – 11-20 lbs
Women with a low BMI need to gain more weight to produce babies with birth weights comparable to women with a normal BMI. Women with a high BMI can deliver babies with higher birthweights with lower gestational weight gain.
Fetal movement
Most women start to feel fetal movement by 18 to 20 weeks gestation in a first pregnancy, in following pregnancies it can occur as early as 15-16 weeks’ gestation. Early fetal movement is felt most commonly when the woman is sitting or lying quietly. The time at which a woman first feels the baby move is termed quickening.
Breast changes during pregnancy
Pregnancy-related breast changes include growth and enlargement, tenderness, darkening of the nipples, and darkened veins due to increased blood flow. In addition, small raised bumps (Montgomery tubercles) appear around the areola in mid-pregnancy. Colostrum is a yellowish fluid secreted by the breast that can be expressed as early as the 16th week of pregnancy. It is replaced by milk on the second postpartum day.
Skin changes during pregnancy
Pigmentation changes are directly related to melanocyte-stimulating hormone (MSH) elevations during pregnancy. Increased pigmentation of some form affects 90% of pregnant women but is more obvious in women with darker skin. This is typically evident in the nipples, umbilicus, axillae and perineum, the linea alba darkens to a brown line called the linea nigra on the midline of the abdomen. Pre-existing moles, freckles and recent scars also become darker. Melasma (also known as chloasma or the mask of pregnancy) is a tan or dark skin discoloration. These are seen in 75% of pregnant women and are commonly found on the upper cheek, nose, lips and forehead. Most of these changes regress after delivery but may recur in future pregnancies.
Striae gravidarum (stretch marks) occur in most pregnant women, usually by the end of the second trimester. In Caucasian women the incidence is reported as 90%. Stretch marks usually occur when weight is lost or gained quickly and the degree to which a woman experiences stretch marks is determined genetically. They usually fade and pale with time.
Hair changes in pregnancy are very common both scalp and body hair. Hirsutism (excessive growth of body hair) is seen in many pregnant women. Thickening of scalp hair during pregnancy is usually followed by increased hair shedding one to four months after delivery.
Sebaceous gland activity is increased during the second half of pregnancy causing greasy skin and possibly acne.
Haemorrhoids and varicose veins
As pregnancy progresses the combination of increased blood volume, circulating progesterone effect on blood vessels and pressure of the growing uterus result in haemorrhoids being more common during pregnancy.
Varicose veins may also appear for the first time during pregnancy due to the relaxant effect of progesterone on blood vessel walls and stasis in leg vessels caused by pressure of the uterus.
The onset of labour is regular contractions resulting in progressive cervical changes. A “show” (blood stained mucus discharge) or spontaneous rupture of the membranes (waters breaking) do not of themselves define the onset of labour. Despite the prevalence of “waters breaking” heralding the start of labour in films and TV dramas, this occurs before regular contractions in less than 8% of pregnancies.
The duration of labour varies with different populations and management practices. A general guideline would be that in most first pregnancies labour lasts less than 12 hours and this is reduced to less than 8 hours in subsequent pregnancies.
Most blood loss related to childbirth occurs within the first hour after birth. In vaginal deliveries up to 500ml of blood may be lost from the genital tract within 24 hours after birth, some of which may appear as clots.