Information for the public
Medical reasons for considering a caesarean section
There are many reasons why you might be offered a caesarean section that is planned in advance.
Most babies move into a head-first position in the womb before they are born. If you have had no problems with your pregnancy and your baby is still bottom first (known as the breech position) at 36 weeks, your midwife or doctor should offer you a procedure called external cephalic version (ECV). This means they gently try to move the baby round to head first by placing their hands on the mother's abdomen and pushing from the outside. ECV does not always work, but if the baby moves so that it is head first, it can usually be born vaginally.
You should not be offered ECV if:
your waters have broken
you are in labour
you have a scar on your womb, or if your womb is irregularly shaped
the health of your baby is at risk
you have any vaginal bleeding
you have an existing medical condition.
If your baby is positioned bottom first at the end of your pregnancy and you are not able to have ECV, or it has not been successful, you should be offered a caesarean section. This reduces the risk of your baby dying or being injured during birth.
If you have placenta praevia, you should be offered a caesarean section.
If you have had a caesarean section before and your doctor confirms at 32–34 weeks that you have a low-lying placenta, you should be offered a colour ultrasound scan to see whether your placenta might be attached abnormally to your womb (a condition known as morbidly adherent placenta). If the results suggest that you do have a morbidly adherent placenta, to help confirm this you should be offered magnetic resonance imaging (MRI) as well. Your doctor should explain about the lack of evidence of any long-term risks to the baby and discuss with you what the MRI involves to make sure you are happy to go ahead.
If the tests show that you are likely to have a morbidly adherent placenta, your doctor should talk with you about having a caesarean section.
This guideline is only about caesarean section. If there are other treatments to reduce the chance of you passing on a viral infection to your baby, your doctor or midwife will talk to you about them.
If you are HIV positive alone, in some circumstances having a caesarean will reduce the risk of passing on the infection to your baby. You should only be offered a caesarean section if:
you are not receiving anti-retroviral therapy or
you are receiving anti-retroviral therapy and you have a high viral load or
you are HIV positive and have hepatitis C.
If your viral load is between the low and high levels, and you are receiving anti-retroviral therapy, you have the option of having either a caesarean section or a vaginal birth because there is not enough evidence that having a caesarean section reduces the risk of passing on the infection to your baby.
You do not need a planned caesarean section if you have hepatitis C virus alone, because it will not reduce the risk of passing the virus to your baby.
If you have hepatitis B, you will not need a caesarean section because this will not reduce the risk of passing on the infection to your baby. With your permission your baby can be vaccinated and have immunoglobulin (an injection of antibodies) once it is born, to reduce the risk of getting hepatitis B.
If you have a first-ever infection of genital herpes in the last 3 months of your pregnancy, you should be offered a caesarean section. But if you had genital herpes before and it comes back at the time of the birth you should not be offered a planned caesarean section, unless you have agreed to take part in a research programme. There is not enough evidence about whether caesarean section cuts down the risk of passing the herpes virus on to your baby if it comes back at the time of birth.
Babies who are not growing well in the womb are known as 'small for gestational age' babies. They have a higher risk of dying or being ill around birth, but there is not enough evidence about whether having a planned caesarean section makes any difference to this risk. You should not routinely be offered a planned caesarean section if your baby is 'small for gestational age' unless you have other complications or you have agreed to take part in a research programme.
A baby born too early has a higher risk of death or complications. However, there is not enough research about whether having a planned caesarean section makes any difference to these risks. If your baby is premature you should not routinely be offered a planned caesarean section unless you have other complications or you have agreed to take part in a research programme.