Mothers who try and push a baby out naturally after having a C-section are more at risk of serious complications, scientists have warned.
Researchers say mothers are safer choosing another Caesarean to avoid harming herself and the baby.
Oxford University academics tracked more than 74,000 births of mothers who had previously had a C-section.
Results showed those who planned a vaginal birth for their next child had higher odds of needing a blood transfusion or being struck down with sepsis.
They were seven times more likely to suffer from uterine rupture, which could cause a stillbirth or the baby needing to be resuscitated.
Mothers who try and push a baby out naturally after having a C-section in the past are at a risk of serious complications, scientists have warned
Gynaecologists have now reassured mothers who have given birth through a C-section that it is safe for them have a vaginal birth.
Women who have a C-section should be counselled about the benefits and harms of their next birth choices, UK clinical guidelines state.
But there isn’t a huge amount of evidence for them to draw on, which prompted the researchers to delve into the risk of complications.
The experts reviewed more than 74,000 births in Scotland between 2002 and 2015 of mothers who had previously had at least one C-section.
WHAT ARE THE MEDICAL REASONS FOR A CAESAREAN?
There are various reasons why a doctor may recommend that you have a caesarean section instead of giving birth vaginally.
If you had complications in a previous pregnancy or birth, or in your current pregnancy, you may be advised to have what’s called a planned or elective caesarean, or a planned repeat caesarean.
If you were planning to give birth vaginally, but complications during labour or birth mean that you’re advised to give birth by caesarean, you’ll have what’s called an unplanned or emergency caesarean.
Here are some reasons why doctors may opt for a planned or emergency caesarean, rather than a vaginal birth:
- You’ve already had at least one caesarean section.
- Your baby is in a bottom-down, or breech, position.
- Your baby is in a sideways (transverse) position, or keeps changing its position (unstable lie).
- You have a low-lying placenta (placenta praevia).
- You have a medical condition, such as heart disease or diabetes.
- You have lost a baby in the past, either before or during labour.
- You’re expecting twins or more.
- Your baby is not growing as well as it should be in your womb.
- You have severe pre-eclampsia or eclampsia, making it dangerous to delay the birth.
A total of 45,579 babies were born by planned C-section and 28,464 by attempted vaginal birth.
Some 1.8 per cent of women who attempted a normal birth experienced serious complications, according to the findings published in the journal PLOS Medicine.
The rate was more than double the 0.8 per cent recorded among those who opted for a C-section.
The odds of uterine rupture was seven times higher, at 0.24 per cent compared to 0.04 per cent.
The tearing of the uterus can cause the mother to suffer severe bleeding, as well as possibly pushing the baby into a gap in the abdomen where it could suffocate.
The odds of women needing a blood transfusion or developing sepsis was twice as high in the group who attempted a vaginal birth.
While the possibility of suffering an injury needing surgery, such as damage to bladder, bowel or ureter, was three times higher in the vaginal birth group.
Eight per cent of women who attempted a normal birth and 6.4 per cent who had a C-section suffered complications with their newborns.
Such complications, grouped together, included stillbirth, the baby being admitted to neonatal unit, or them needing to be resuscitated.
Of the women who had a planned vaginal birth, 71.6 per cent were successful. The rest needed an emergency C-section.
They were significantly more likely than those delivering by planned C-section to experience all serious complications.
The experts, led by PhD student Kathryn Fitzpatrick, stated that the overall risk of complications were small for either type of delivery.
The team said mothers should not be afraid of choosing a vaginal birth if they want to and are able to accept the risks.
Andrew Shennan, professor of obstetrics, Kings College London, said: ‘We know that, overall, vaginal births are the safest overall, if you can achieve it.
‘If a vaginal delivery is attempted after a previous caesarean there is a very small risk of womb rupture and bleeding, which can be safely managed in hospital.’
The increased risk of uterine rupture in women who attempt vaginal birth may be caused by the scar from a previous C-section tearing under the pressure of labour contractions. It may lead to doctors deciding to perform an emergency C-section.
A previous caesarean section has always been recognised by the medical profession as one of the potential risk factors for uterine rupture, the NHS states.
The Royal College of Obstetricians and Gynaecologists say uterine ruptures strike every one in 200 women who plan vaginal deliveries after a C-section.
Dr Pat O’Brien, consultant obstetrician and spokesperson for the RCOG, said the research provided more useful data to help guide women’s choices.
He said: ‘A detailed conversation with a woman and her senior obstetrician should take place so she can make an informed choice about the safest way she can plan to give birth and be supported by a team of specialists.
‘Women can be assured that in most cases it is possible and safe to have a vaginal birth, or a planned repeat Caesarean birth, after a previous Caesarean birth.’
Elizabeth Duff, a senior policy adviser at The National Childbirth Trust, said: ‘This latest research has confirmed that the risks associated with vaginal birth after caesarean and a planned repeat caesarean are low.
‘Most women are able to have a vaginal birth safely after a previous caesarean without complications.
‘But outcomes will vary and depend on their obstetric history including the reasons behind why they had a C-section in the first place.’
Figures show around one in every four pregnant women in the UK now gives birth through a C-section.
Just 19.7 of babies in Britain were born through C-sections in 2000. In contrast, the figure was 26.2 per cent in 2015.
Experts speculate women are opting for C-sections, even if they don’t have medical reasons, in fear of labour pain and believing a C-section is safer.
C-sections can be life-saving interventions for both the mother and her child when complications occur, such as bleeding.
Ms Fitzpatrick said: ‘Our findings can be used to counsel and manage women with previous caesarean section and should be considered alongside existing evidence.’
OLDER MOTHERS THREE TIMES MORE LIKELY TO SUFFER COMPLICATIONS IF THEY HAVE A C-SECTION
Older mothers who give birth by caesarean are three times more likely to experience severe complications than those who give birth naturally, a study found.
Those over 35 – classed as geriatric mothers – were at greater risk of serious complications such as haemorrhaging following childbirth if they underwent the surgical procedure.
Even in younger women, the chances of problems after a caesarean were 1.5 times higher for a mother than for vaginal births.
Experts said the findings raise serious questions over current guidelines for the procedure, particularly when it comes to older mothers.
French researchers looked at births across six regions in France and compared 1,444 mothers who suffered severe complications after birth with 3,464 mothers who had more straightforward deliveries.
Although severe maternal complications are uncommon overall, they found caesareans were more likely to result in severe complications after delivery, whether surgery was performed before or during labour.
Most complications involved haemorrhage after delivery which happens when the uterus does not contract strongly enough, allowing blood vessels bleed freely.
The findings were published in the Canadian Medical Association journal.