Anterior placenta
An anterior placenta is when the placenta attaches to the front wall of the uterus. This is a normal place for the placenta to implant and develop, but there are a few things to be aware of if you have one.
What is the placenta?
The placenta is an organ that helps your baby grow and develop. It’s attached to the lining of the womb and is connected to your baby by the umbilical cord. The placenta passes oxygen, nutrients and antibodies from your blood supply to your baby. It also carries waste products from your baby to your blood supply, so your body can get rid of them.
What is an anterior placenta?
The placenta develops in the first few weeks of pregnancy, wherever the fertilised egg embeds itself. This could be along the top, sides, front or back wall of the uterus. If the placenta attaches to the front, this is called an anterior placenta.
People sometimes think that having an anterior placenta is linked to having a low-lying placenta but it is not. A low-lying placenta (also known as placenta praevia) is when the placenta attaches lower down and may cover a part of or all of the cervix (the entrance to the womb).
How will I know if I have an anterior placenta?
You’ll find out whether you have an anterior placenta during your second ultrasound scan when you are 18 to 21 weeks pregnant.
Can an anterior placenta cause complications?
This is very unlikely. The front wall of the uterus is a normal place for the placenta to implant and develop. An anterior placenta will still do its job of nourishing your baby, but there are some things to be aware of if you are diagnosed.
Feeling your baby’s movements
Most women usually feel their baby move between 18 and 24 weeks. If this is your first pregnancy, you may not notice your baby’s movements until you are more than 20 weeks pregnant.
Having an anterior placenta can make it a bit harder to feel your baby move because your baby is cushioned by the placenta lying at the front of your stomach. However, it’s very important that you never assume that having an anterior placenta is a reason why you can’t feel your baby move.
Get to know your baby’s movements and be aware of them throughout your pregnancy. Contact your midwife or maternity unit immediately if you think your baby’s movements have slowed down, stopped or changed. It’s always best to get checked.
Some women may feel particularly anxious about their baby’s movements, especially if they’ve had difficult experiences in previous pregnancies. Talk to your midwife about how you feel. They may be able to reassure you or help you get more help and support, if you need it.
Lower back pain
You may have lower back pain if you have an anterior placenta. Irritable back pain can be common in pregnancy and there are things you can do to try to ease it.
Screening and diagnostic tests
An anterior placenta can make it more difficult to perform certain tests, such as amniocentesis. Not all women are offered this test during pregnancy. You’ll only be offered this test if the results of your screening tests show that your baby has a high risk of certain conditions, such as Down’s syndrome.
The test involves inserting a long, thin needle through the stomach into the amniotic sac to remove a sample of cells so doctors can test for health conditions. Having an anterior placenta can make this more difficult, but doctors will use an ultrasound scanner to guide the needle and avoid the placenta. An ultrasound scanner is used to guide the needle, which significantly reduces the risk of injury.
There is a small risk of miscarriage after an amniocentesis test, regardless of where the placenta is. Having an anterior placenta does not increase this risk.
Your baby’s position in the womb
Having an anterior placenta increases the chances of the baby being in a back-to-back (occipitoposterior) position. This is when the baby’s head is down, but the back of their head and their back is against your spine.
If your baby is in a back-to-back position when you go into labour, it’s likely that your baby will turn into the best position for birth and you will have a normal vaginal delivery. But having a baby in a back-to-back position during labour does increase the chances of:
- a longer labour
- a more painful labour
- a caesarean section
- assisted birth.
Talk to your midwife or doctor if you have any concerns about having an anterior placenta.