The Third Stage of Labour (The Birth of the Placenta)
The third stage of labour is defined as the time between the birth of the baby and the birth of the placenta. Assuming you have had a normal labour, after the baby comes out, your midwife will pass your baby up onto your abdomen with the umbilical cord still attached. Your midwife or a nurse will then dry the baby and make sure your baby is breathing well as you meet your baby for the first time.
A mother’s first meeting with her baby triggers a surge of oxytocin, the so-called “love hormone” that is also the hormone that makes the uterus contract during labour and that causes milk letdown in breastfeeding. This oxytocin surge makes the uterus keep on contracting; as the uterus shrinks in size, it causes the placenta to separate off (imagine a sticker on the inside of a shrinking balloon) so that the mother can push the placenta out. Once the placenta is out, the uterus keeps contracting down to cut off all the blood vessels that have been supplying the placenta throughout the pregnancy.
When this process does not work properly for any reason, it can lead to postpartum hemorrhage (PPH), or excessive bleeding after birth. Several factors can affect this process. If the mother is feeling stressed or unsafe, stress hormones (catecholamines) can prevent the natural oxytocin surge. If the uterus has been very stretched (e.g. twin pregnancy, a very large baby, or excess amniotic fluid) it may not be able to contract down properly. If the mother has had a very long labour or has pushed for a very long time (more than 3 hours), the uterus might be very tired, and might not be able to contract properly. If you have had a synthetic oxytocin induction or augmentation in labour, this can affect your body’s production of natural oxytocin after the birth. When the uterus does not contract well after a birth, this is called “uterine atony.”
Currently the Society of Obstetricians and Gynecologists of Canada (SOGC) recommends “active management of the third stage” for all women in all settings because “it reduces the incidence of postpartum hemorrhage (PPH) due to uterine atony.” The SOGC bases this on an International Joint Policy Statement by the International Confederation of Midwives (ICM) and the International Federation of Gynecology and Obstetrics (FIGO). Active management, as defined in this policy statement, includes three components:
- A shot (needle) of synthetic oxytocin within one minute of birth of the baby
- The midwife gently pulls on the placental end of the umbilical cord (after the cord has been cut) with counter pressure above the pubic bone to guide the placenta out
- Uterine massage after the delivery of the placenta, as
This is based on evidence from several large randomized controlled trials, which have been summarized in a meta-analysis. The meta-analysis indicates that active management, when compared with “expectant management,” reduces rates of PPH (blood loss over 500 mL) and severe PPH (blood loss over 1000 mL) by approximately 60 percent, and also reduces the need for blood transfusion, the need for additional drugs to control bleeding, and rates of anemia for women with any risk factors for bleeding. The problem with these studies, however, is that both “active management” and “expectant management” were done differently in different studies.
The evidence is clear that active management should be used for all women who have risk factors for PPH, such as having a PPH at a previous birth, abnormal uterine anatomy (e.g. fibroids), a very-stretched uterus (twins, extra amniotic fluid), if they have had six or more babies, low hemoglobin, placental abnormalities, obstetric interventions during labour (augment or induction), blood clotting problems, or uterine muscle exhaustion from either very long or very short labours. What is more complicated, however, is whether active management should be routine for low risk women birthing with British Columbia midwives.
The same meta-analysis mentioned above found that active management did not provide as clear a benefit for women at low risk of PPH. Although active management still reduced overall blood loss, it did not make any difference for severe PPH (blood loss greater than 1000mL); most healthy pregnant women can tolerate some blood loss after a birth with no problems. Also, active management increased women’s afterpains (uterine cramping after the birth) and increased the chance that women had to return to the hospital in the postpartum period (more than 48 hours after the birth) for excess bleeding that occurred later on. The finding that active management does not make as much difference for low-risk woman has also been found by other studies of low- risk women cared for by midwives.
According to one study of third stage management by maternity care providers (midwives, obstetricians, and family doctors) in BC, midwives, as a group, are most familiar with the SOGC guideline recommending active management, and also the most likely to reject it. Even though many midwives in BC reject the SOGC guidelines regarding routine active management of the third stage, studies have demonstrated that in BC, midwives and
physicians have similar PPH rates at the births they attend. Most studies of postpartum hemorrhage do not evaluate the type of autonomous, community-based midwifery that is practiced in BC. The most significant difference in BC midwifery practice, in both home and hospital, is that midwives stay with their clients for several hours after the birth. Thus, midwives in BC can observe and react quickly to a developing PPH.
Other aspects of the trials in the Cochrane review are different from BC midwifery practice. Hastie and Fahy argue that the Cochrane review defined ‘expectant management’ only as the absence of active management. Instead, midwives offer ‘psychophysiological’ (or physiologic) management, which has several components. Safe physiologic management depends on a woman’s own hormones, particularly oxytocin, to stimulate the uterine contractions that cause the placenta to separate. The hormones associated with stress, fear, or excitement, such as adrenaline, noradrenaline, and cortisols, will interrupt a woman’s production of oxytocin.
Thus, correct physiological management requires a care provider that the woman trusts, and a warm, private environment that feels safe for the woman, without distracting conversations or over-excitement. Skin-on-skin contact with baby and early breastfeeding also enhance the mother’s oxytocin. The umbilical cord should be left intact until it stops pulsing, and the woman should be in a comfortable, upright position to take advantage of gravity (Hastie and Fahy 2009). Finally, the woman must be well nourished and physically healthy, must be mindful and active in the process of birthing her placenta, and should be open to using synthetic oxytocin if necessary.
Who should plan on active management:
- Women with twins or with extra amniotic fluid
- Women having their sixth (or higher) baby
- Women who have an oxytocin induction or augmentation of labour
- Women who start labour with low hemoglobin (anemia) or a preexisting blood clotting disorder
- Women who have had a postpartum hemorrhage before
- Women who know they have uterine fibroids or a bicornuate or septate uterus
- Women who know their placenta is not normal
When should the plan switch to active management?
- If your labour needs oxytocin for augmentation
- If you have a long labour (more than 12 hours of active labour), if you push for a long time (more than 3 hours) or if your labour is very short (less than 2 hours)
- If you have a vaccuum or forceps delivery
- If you are feeling worried, upset, or stressed after your baby is born
- If your baby needs to be taken to the warmer for assessment
Begley CM, Gyte GMI, Devane D, McGuire W, Weeks A. 2011. Active versus expectant management for women in the third stage of labour (review). Cochrane Database of Systematic Reviews 2011, Issue 11. Art. No.: CD007412.
Davis D, Baddock S, Pairman S, Hunter M, Benn C, Anderson J, Dixon L, Herbison P. 2012. Risk of Severe Postpartum Hemorrhage in Low- Risk Childbearing Women in New Zealand: Exploring the Effect of Place of Birth and Comparing Third Stage Management of Labor. Birth 39(2): 1-8.
Fahy K, Hastie C, Bisits A, Marsh C, Smith L, Saxton A. 2010. Holistic physiological care compared with active management of the third stage of labour for women at low risk of postpartum haemorrhage: A cohort study. Women and Birth. Doi:10.1016/j.wombi.2010.02.003.
Hastie, C, Fahy KM. 2009. Optimising psychophysiology in third stage of labour: Theory applied to practice. Women and Birth 22: 89-96.
International Confederation of Midwives, International Federation of Gynecology and Obstetricians. 2003. Management of the third stage of labour to prevent postpartum hemorrhage. Journal of Obstetrics and Gynecology Canada 25(11):952-953.
Janssen PA, Saxell L, Page LA, Klein MC, Liston RM, Lee SK. 2009. Outcomes of planned home birth with registered midwife versus planned hospital birth with midwife or physician. Canadian Medical Association Journal 181(6-7): 377-383.
Prendiville WJ, Elbourne D, McDonald S. 2000. Active versus expectant management in the third stage of labour. Cochrane Database System Review 2000(3). Art. No.: CD000007.
Tan WM, Klein MC, Saxell L, Shirkoohy,SE, & Asrat G. 2008. How do physicians and midwives manage the third stage of labor? Birth 35(3) 220-229.