By The PPH Foundation
In postpartum haemorrhage, tone refers to the ability of the uterus to contract firmly after delivery. When the uterus fails to contract effectively, a condition known as uterine atony, blood vessels that supplied the placenta remain open, leading to heavy and sometimes life-threatening bleeding. Uterine atony is the leading cause of postpartum haemorrhage globally.
According to the World Health Organization, postpartum haemorrhage accounts for about 27 percent of maternal deaths worldwide, with the majority occurring within the first 24 hours after birth. Research published in leading obstetric reviews shows that uterine atony is responsible for approximately 70 to 80 percent of these cases. This makes tone the most critical factor in preventing maternal deaths linked to excessive bleeding.
Dr Kireki Omanwa, President of the Kenya Obstetrical and Gynaecological Society and End PPH Initiative Co Lead, explains that after delivery, the uterus must contract immediately and firmly to compress the blood vessels at the placental site. When this contraction is inadequate, bleeding continues unchecked. He notes that uterine atony can occur even in women with no obvious risk factors, which is why vigilance during the immediate postpartum period is essential.
Several factors increase the risk of uterine atony. These include prolonged labour, overdistension of the uterus due to multiple pregnancy or a large baby, infection, high parity, and the use of certain medications during labour. Severe anaemia can also worsen the effects of blood loss, making even moderate haemorrhage dangerous.
The most important sign of uterine atony is excessive vaginal bleeding after birth. Clinically, the uterus feels soft or boggy on abdominal examination instead of firm and contracted. A rising pulse rate, falling blood pressure, pallor, dizziness, or restlessness may signal worsening blood loss. Early recognition of these signs can mean the difference between life and death.
Prevention begins before delivery. Active management of the third stage of labour, including the timely administration of uterotonics such as oxytocin, significantly reduces the risk of postpartum haemorrhage. The WHO recommends routine use of uterotonics for all births. Skilled birth attendance, close monitoring in the first hour after delivery, and preparedness with emergency supplies are also critical.
Management of uterine atony requires rapid, coordinated action. Immediate uterine massage can stimulate contraction. Additional uterotonics may be administered, including oxytocin infusions or other agents where appropriate. If bleeding persists, interventions such as tranexamic acid, uterine balloon tamponade, surgical procedures, or blood transfusion may be necessary. Timely referral to higher level facilities saves lives when first line measures fail.
Dr Kireki emphasizes that no woman should die from a condition that is both predictable and treatable. Strengthening health systems, ensuring consistent availability of uterotonics, and training health workers in emergency response are fundamental to ending preventable maternal deaths from uterine atony.
Sources
World Health Organization, Trends in Maternal Mortality
World Health Organization, WHO Recommendations for the Prevention and Treatment of Postpartum Haemorrhage
FIGO Guidelines on the Management of Postpartum Haemorrhage
Kenya Obstetrical and Gynaecological Society Clinical Guidance on PPH
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