Doctors in Dublin’s maternity hospitals are performing an increasing number of life-saving hysterectomies on mothers who have previously had caesarean sections. The upsurge in the number of births by c-section has led to a marked increase in emergency operations to remove women’s wombs due to a condition called placenta accreta, according to a new study.
The problem is caused where the placenta, or afterbirth, attaches too deeply into the wall of the womb. The risk of the condition is increased by the presence of scar tissue from previous caesareans.
Doctors from the Rotunda, Holles Street and the Coombe hospitals analysed charts of all patients who had emergency hysterectomies after giving birth in the 40 years between 1966 and 2005. Of the 320 cases, 43 of them were due to placenta accreta. It accounted for only one in 20 emergency hysterectomies from 1966 to 1975 but 47% of those between 1996 and 2005 when almost half (20) the cases occurred. The caesarean rate rose from 6% to 19% over the same period and now stands at about one in four births.
The findings are consistent with international studies. One study in the Netherlands where the rate of c-sections was 14% found that accreta accounted for 50% of cases of peripartum hysterectomy.
Writing in the American Journal of Obstetrics & Gynecology, the authors of the Irish survey say: “There is a concern that there will be a rise in the number of obstetric hysterectomies required in the future because of placenta accreta alongside significant maternal morbidity.”
The doctors cite international studies that show women who have had one previous c-section have more than double the risk of emergency hysterectomy in the next pregnancy and those who have had two or more have at least 18 times the risk.
“The only thing you can do is be cautious with the number of c-sections that are done,” said Fergal Malone, professor of obstetrics and gynaecology at the Rotunda hospital and the Royal College of Surgeons. “We are seeing more patients back again for their second and third c-section and it would appear that the lining of the uterus is much stickier than if you never had one, therefore the placenta is probably going to be more adherent.
“When it comes to take the placenta out it is stuck, and that leads to a much higher chance of having to do a hysterectomy.”
Tracy Donegan, author of The Better Birth Book, said: “This is an unfortunate side-effect of the increase in the caesarian rate, but I don’t think women really understand the implications. It has become so routine now women don’t consider it a big deal even though it’s major abdominal surgery.”
Donegen said the rate of caesareans has also increased because hospital policy is to induce births that are more than 10 days past the due date. “Nearly half of those women, especially first-time mothers, are likely to have a c-section because they’ve been induced at 10 days,” said Donegan, founder of Doula Ireland, an organisation of birth assistants.
“The World Health Organisation recommends the rate be 15% at the most,” said Donegan. “Anything above that is unnecessary. We’re at about 25% nationally, but some hospitals are up to 29%.”
It is not automatically the case that a woman who has had one baby by caesarean has to have all subsequent children the same way.
“Most women should be encouraged after having a caesarean to go for a normal vaginal birth, assuming everything is fine,” said Donegan. “The three Dublin hospitals have a fairly good record of encouraging women to have vaginal birth after caesarean (VBAC) because with the next pregnancy you are looking at a placenta accreta. Women aren’t getting the information so they can make that informed decision as to whether they go for VBAC or another caesarean.”
Malone said the number of women choosing caesareans because they are “too posh to push” is exaggerated. “It’s much spoken about in the press but in reality the number of patients who come in for maternal request c-sections is very small.”
He said the recent increase in c-sections was partly due to changes in practice. “Up until about 10 years ago delivering breech babies vaginally was commonplace. But recent data shows that they have about five times higher chance of brain injury than a breech baby delivered by caesarean. Very few babies that are breech are now delivered vaginally. Also, patients are giving birth much older now than in the past. About 25% of babies born in the Rotunda are to mothers over 35, whereas 15 years ago it was only about 15%.”
Emergency hysterectomies due to other causes, such as rupture of the womb, fell in the last four decades as medical techniques have improved, according to the study.