What is the placenta?
The placenta is an organ that helps your baby grow and develop. It is attached to the lining of your womb (uterus) and connected to your baby by the umbilical cord. The placenta sends oxygen, nutrients and antibodies to your baby from your blood supply. It also carries waste products away from your baby, back to your blood supply, so your body can get rid of them.
What is an anterior placenta?
The placenta begins to grow 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 your womb.
An anterior placenta is when the placenta attaches at the front of the womb.
An anterior placenta is not the same as a low-lying placenta. A low-lying placenta, also called placenta praevia, is when the placenta attaches lower down near the entrance of the womb.
How will I know if I have an anterior placenta?
If you have an anterior placenta you would normally find out about it at your 18-21 week ultrasound scan (for most people this will be the second scan).
Some people find out that they have an anterior placenta at their first ultrasound scan, although the placenta may move from this position as pregnancy progresses.
Can an anterior placenta cause complications in pregnancy?
It is very unlikely that an anterior placenta will cause any complications. The front wall of the womb is a normal place for the placenta to be. An anterior placenta will do its job of nourishing your baby. But there are some things however to be aware of if you have one.
Feeling your baby’s movements
Everyone is different but most people first feel their baby move between 18 and 24 weeks, wherever their placenta is positioned. If this is your first pregnancy, you may not notice your baby’s movements until you are more than 20 weeks pregnant. If you have been pregnant before, you may feel movements as early as 16 weeks.
Tell your midwife if you have not felt your baby move by 24 weeks.
Feeling your baby move is a sign that they are well so it is important to get to know how your baby moves. There is no set number of normal movements you should be feeling – every baby is different. The important thing is to get to know your baby's usual movements from day to day.
Some people with an anterior placenta will have no issues feeling their baby move but it can make it a bit harder to feel the movements because they are cushioned by the placenta at the front of your stomach.
It is very important never to assume that your anterior placenta is the reason you cannot feel your baby move.
Contact your maternity unit straight away if you think your baby’s movements have slowed down, stopped or changed. It is always best to get checked.
You may feel anxious about your baby’s movements, especially if you have had difficult experiences in other pregnancies. Talk to your midwife about how you feel. They may be able to reassure you or will help you get more support if you need it.
Find out more about baby movements in pregnancy.
Screening and diagnostic tests
An anterior placenta can make it harder to do some medical tests, such as amniocentesis. You will only be offered this procedure if screening tests show that your baby has a high risk of certain genetic conditions, such as Down’s syndrome
During amniocentesis, a long, thin needle is gently pushed through your stomach into the amniotic sac to take a sample of cells. These cells are then tested for health conditions affecting the baby.
Having an anterior placenta can make the procedure more difficult, but your doctor will use an ultrasound scanner to guide the needle and avoid the placenta. Using an ultrasound scanner greatly reduces the risk of injury.
There is a small risk of miscarriage after an amniocentesis test for any person who is pregnant. This is estimated to occur in up to 1 out of every 200 women and birthing people who have amniocentesis. Having an anterior placenta does not make this risk higher.
Read more about screening and diagnostic tests in pregnancy.
Your baby’s position in the womb
Having an anterior placenta means there is more chance of your baby being in a back-to-back position. This is also called occipitoposterior. It means your baby’s head is down, but the back of their head and their back is against your spine.
Some people believe that having an anterior placenta makes it more likely that you will have lower back pain. This may be because having an anterior placenta means there is more chance of your baby being in a back-to-back position.
Back pain is common in pregnant people and there are things you can do to try to make it feel a bit better.
If your baby is in a back-to-back position when you go into labour, they will probably turn and get into the best position for a vaginal birth, and you will have a normal vaginal delivery. But if your baby stays in a back-to-back position during labour, it is more likely you will have:
- a longer labour
- a more painful labour
- a caesarean section (c-section)
- an assisted birth
Planning for labour may help you feel more prepared. Talk to your midwife or doctor about where you want to give birth and how you want to deliver your baby. You may also find it helpful to make a birth plan.
Talk to your midwife if you are feeling anxious about giving birth. They may be able to reassure you.
Find out more about positive ways to prepare for labour.
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