Low-lying placenta (placenta praevia)

The placenta is your baby’s support system in the womb. If the placenta doesn’t work properly, your baby is at risk of health problems.

The placenta processes your baby’s nutrients, waste and oxygen. 

In most pregnancies the placenta attaches to the side of the womb but for some women the placenta attaches lower down and may cover a part or all of the cervix (entrance to the womb). This is called low-lying placenta or placenta praevia.

This often shows up in early ultrasound scans when it is called low-lying placenta. In 90% of cases, the placenta moves upwards as the womb grows. For some women, however, the placenta continues to lie in the lower part of the uterus after 20 weeks. This affects 1 in 200 births.

When this happens it is called placenta praevia. If the placenta covers the cervix, this is known as major placenta praevia.

A note on the difference between placenta praevia and anterior placenta

People sometimes think that low-lying placenta is linked to having an anterior placenta but this is not correct. Anterior placenta simply means the placenta is on the front (belly side) of the womb rather than attached to the back of the womb. Having an anterior placenta is normal and does not cause complications. 

How would I know if I had placenta praevia?

Placenta praevia is usually spotted during your normal ultrasound scans but other signs are:

  • painless vaginal bleeding in the second or third trimester
  • baby in an unusual position in the second or third trimester, breech for example or failure of the head to engage in the pelvis just before labour starts.

If you have any bleeding, contractions or pain in pregnancy you should always contact the hospital.

You may have a transvaginal scan (where the probe is placed inside the vagina) to confirm whether you have placenta praevia.

The risk factors for placenta praevia

In many cases the cause of placenta praevia is unknown but the following risk factors are associated with the condition:

  • Maternal age: it is more common in women who are over 40 years
  • Previous caesarean section (the risk increases slightly with each one)
  • IVF
  • Previous placenta praevia
  • Multiple pregnancies
  • Smoking
  • Previous abortion or surgery in the womb

Treatment for placenta praevia

You will have extra scans if you are found to have a low-lying placenta in a routine scan.

An extra scan is recommended at 32 weeks if:

  • you had a caesarean section before
  • your placenta covers the cervix (major placenta praevia)
  • your placenta is in an anterior position (at the front of the womb) and you have had a previous caesarean section.

If your placenta does not cover the cervix and you have no bleeding during your pregnancy, your extra scan should happen around 36 weeks instead. 

There is a risk that you may bleed in the second half of pregnancy (sometimes caused by having sex). Bleeding from placenta praevia can be heavy. If you bleed contact your hospital immediately.

If you have major placenta praevia (the placenta covers the cervix) you may need to stay in hospital after 34 weeks of pregnancy even if you have had no symptoms. There is a small risk that you could bleed suddenly and severely, which may mean that you need an urgent caesarean section. If you are bleeding the baby may need to be delivered.

Placenta praevia is linked to spontaneous preterm delivery and PPROM (waters breaking early), a major cause of premature labour.

The birth

Your obstetrician and / or midwife is likely recommend delivery in hospital, rather than a home setting, and caesarean section might be considered the safest option if the placenta is less than 2cm away from the internal os (the part of the cervix that opens into the uterus).

If you have major placenta praevia (where it covers the cervix) or if the placenta is very close to the cervix you will need to have a caesarean section because the placenta lies in the way of your baby being born.

Sources

  1. RCOG (2011) Information for you: A low-lying placenta (placenta praevia) after 20 weeks, Royal College of Obstetricians and Gynaecologists
  2. RCOG (2011) Placenta praevia, placenta praevia accreta and vasa praevia: diagnosis and management, Green-top Guideline No 27, Royal College of Obstetricians and Gynaecologists
  3. BMJ Best Practice (accessed Oct 2016) http://bestpractice.bmj.com/best-practice/monograph/667/diagnosis/history-and-examination.html
  4. BMJ Best Practice (accessed Oct 2016) http://bestpractice.bmj.com/best-practice/monograph/667/basics/aetiology.html
  5. J David, Steer P et al (2010) High risk pregnancy, management options, Elsevier Saunders
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Last reviewed on September 12th, 2016. Next review date September 12th, 2019.

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Comments

Please note that these comments are monitored but not answered by Tommy’s. Please call your GP or maternity unit if you have concerns about your health or your baby’s health.
  • By Zanna (not verified) on 17 Jul 2019 - 18:35

    my wife is 26 wks and having placenta lowlying what can we do now

  • By Nelly (not verified) on 8 Jul 2019 - 16:58

    I had an anomaly scan today and i'm 22weeks gone.The doctor conducted a scan on me and was told that i have a low-lying placenta.Pls i want to know if the placenta will move up later and if there's a risk involved because i'm not bleeding

  • By Divya (not verified) on 8 Jul 2019 - 12:29

    Hello Ma'am,
    Now I'm 20 weeks 2 days pregnant. When I had my anomaly scan at 15.6 weeks, it showed that I have anterior low lying placenta and placental venous lake seen overlying internal os which is covering the cervix. It's my second pregnancy My Gynecologist told me it is very risky for me n my baby. She also told me for strict bed rest.If my placenta doesn't move upwards, is it possible to have a vaginal delivery

  • By Sarin Mythry (not verified) on 15 May 2019 - 18:27

    Hi my wife is now almost 20 weeks pregnant. Last week she had heavy bleeding and even 2 big clots was passed. Doctors say , since placenta has moved high from low lying point, due friction in motion of placenta , bleeding took place, and there is some collection of blood about 3cm in area near placenta. Doctor also told , there might be another episode of bleeding due to blood collection near placenta or it might get subside. Even now my wife is having light bleeding. Can anyone suggest me, am worried. Is it harmful to baby and growth and also to my wife. And can this happen in low lying placenta and still they go on safely to deliver baby after this pregnancy phase even with this bleeding without pain.

  • By parami (not verified) on 15 May 2019 - 10:30

    I had taken anamoly scan during 18 weeks of pregnancy. The report says that iam having type ii low lying posterior placenta previa touching the internal os. My doctor advised me to put maintane 500 injection up to 8th month. Will it possible for vaginal delivery or it will end with C-section. Plz reply mam

  • By Heena (not verified) on 14 May 2019 - 01:27

    Sir i m 18 week pregnantand my placanta is lower end away from os is only 3 cm.. I m very scread is it all ok or not plz tell me

  • By Manju Kubendran (not verified) on 13 May 2019 - 11:46

    Hi.. This is my 2nd pregnancy . First girl baby is normal.Am now 34 weeks pregnant placenta posterior and low lying 1.4 cms away from OS .. Normal delivery is possible

  • By Manju Kubendran (not verified) on 13 May 2019 - 11:45

    Hi.. This is my 2nd pregnancy . First girl baby is normal.Am now 34 weeks pregnant placenta posterior and low lying 1.4 cms away from OS .. Normal delivery is possible

  • By Siobhan (not verified) on 10 May 2019 - 21:40

    Hi I have just had my scan in currently 36 weeks at my 32 week appointment I was told it was 1cm away from os but my 36 week one said it was 0.7cm away does this mean it has moved closer to my cervix

  • By Siobhan (not verified) on 10 May 2019 - 21:39

    Hi I have just had my scan in currently 36 weeks at my 32 week appointment I was told it was 1cm away from os but my 36 week one said it was 0.7cm away does this mean it has moved closer to my cervix

  • By Nadia (not verified) on 6 May 2019 - 11:43

    Hi,
    I am 33 weeks pregnant and been told that placenta is completely lying on OS. I found out at 20 weeks scan that I have low lying placenta but it still there at 33 weeks.
    I am going for another scan at 36 weeks.
    I don’t know what risks it will bring and what I should be doing and is there any chances it will move up itself at this stage?
    Thanks

  • By Kirti (not verified) on 29 May 2019 - 03:42

    what u did precautions at that stage.i m in same boat.i m at 30 weeks pregnancy and placenta cover the is.help me plz

  • By Nadia (not verified) on 4 May 2019 - 19:24

    Hi,
    I am 33 weeks pregnant and was told last week that placenta is totally covering my cervix which hasn’t moved since 20 weeks when I first found out. I wanted to know is there still chances of placenta to move by 36 weeks?
    And I am not having any bleeding or anything so just curios how serious it is and am I still going to have a C section?
    Thanks

  • By Dolly (not verified) on 28 Apr 2019 - 06:05

    Im on my 28 week of pregnancy... last day scan show placenta is grade 1 n lower edge is 2 cm from internal os.. 20 week scan also shows the same previous.. but now doctor told me to do conplete bed rest.. so there is chances that placenta will come upwards??? Or wl i complete my 36 weeks for a safe delivery???

  • By Fajila (not verified) on 19 Jun 2019 - 06:47

    Same problem me.im in 22 weeks my ultrasound report show that anterior low lying placenta margin 2.0 from internal os if it is risk from baby plz tell me.. R u delivered normal or c section.what happened to you plz tell me

  • By Louise (not verified) on 27 Apr 2019 - 13:36

    Hello, I woke this morning to bleeding when I wiped. Very scary. Went to EPAU and thankfully the baby is fine on the scan. They noticed the placenta is low lying and believe this to be the cause of bleeding.

    They said its not covering the cervix. Can someone tell me how the low lying placenta can cause bleeding?

    Thanks so much

    Louise

  • By Emma Wolfe (not verified) on 26 Apr 2019 - 08:29

    Hi at my anamoly scan the tech I dentified that my placenta covers my cervix and placenta could be seen on both posterior and anterior walls. He also raised concern that some blood vessels could be seen travelling under the baby. From what I can research thus is possible placenta previa with previa vasa. What does this mean for me and my baby. This is baby no 5 all previous normal healthy delivery of large babies. I'm really stressing myself out with worry.

  • By Mary (not verified) on 26 Apr 2019 - 06:18

    At my last ultrasound at 35+2 my placenta was still lying low at 1.7cm away from the uterus. Do you think I could move or be safe to deliver vaginal. The doctor seem confused of what to do. He kind say it was up to me but I want to do what's best for my baby and me.

  • By Salma (not verified) on 25 Apr 2019 - 06:24

    I have anterior low lying placenta at 15 weeks pregnancy with mild spotting whenever I go to the toilet.is there any chance it will move up?

  • By Midwife @Tommys on 25 Apr 2019 - 13:02

    Hi - Thank you for your message.
    A low lying placenta can move up and away from the cervix as the uterus grows. if you have look at the clip on the page above it is explained in detail.
    Sorry to hear that you have been having a difficult time in this pregnancy. Having a low lying placenta can mean that bleeding can happen in pregnancy, its just very important that each time you do bleed you go into hospital even if its happens regularly and everything is ok.
    Best wishes
    Tommy's midwife

  • By Iqu sik (not verified) on 7 May 2019 - 11:39

    I have same issue and my belly will so hard when go for sleep feeling so pain in stomach only sleep straight no right side no left side,now i'm in 19 weeks can it's possible if placenta low lying im giving brith normal?or its must surgery?

  • By Abbie (not verified) on 12 Apr 2019 - 19:37

    Hi, I’m 24 weeks today and was told at my 20 week scan that my placenta is completely covering the OS. There have been talks of a C section and my midwife says the chances of a placenta completely covering to move is slim. I’ve had some bleeding and been checked but am very nervous about early birth etc. Has anyone had any experience with this and it moving? Thankyou x

  • By Midwife @Tommys on 24 Apr 2019 - 10:13

    Hi
    You should have been booked for a repeat scan at 32 weeks to assess if the placenta has moved away from the os as the lower segment of the uterus develops.
    If the placenta remains in the same position then delivery will be Caesrean Section-the timing of this will be discussed by your obstetrician.

    There is a risk that you may bleed in the second half of pregnancy (sometimes caused by having sex). Bleeding from placenta praevia can be heavy. If you bleed contact your hospital immediately.

    If you have major placenta praevia (the placenta covers the cervix) you may need to stay in hospital after 34 weeks of pregnancy even if you have had no symptoms. There is a small risk that you could bleed suddenly and severely, which may mean that you need an urgent caesarean section. If you are bleeding the baby may need to be delivered.
    Take care
    Tommys' midwife

  • By Star (not verified) on 28 Mar 2019 - 19:48

    Hey there.

    You've read through many of the questions here and answers, but I'm not seeing one answered I'm curious about.

    If you have low-laying placenta, can it actually move closer to the cervical opening.. or does it only stay put or move away from?

    Thank you. :)

  • By Midwife @Tommys on 24 Apr 2019 - 11:45

    Hi Star
    It would be extremely rare for the placenta to move down unless it was already partially covering the cervix and therefore not able to move up when the lower segment of the uterus starts to develop after 24 weeks. If the placenta is even partially covering the cervical os, the only safe way to deliver the baby is by Ceaserean section.

    There is a risk that you may bleed in the second half of pregnancy (sometimes caused by having sex). Bleeding from placenta praevia can be heavy. If you bleed contact your hospital immediately.

    If you have major placenta praevia (the placenta covers the cervix) you may need to stay in hospital after 34 weeks of pregnancy even if you have had no symptoms. There is a small risk that you could bleed suddenly and severely, which may mean that you need an urgent caesarean section. If you are bleeding the baby may need to be delivered.
    The link has more information for you-
    https://www.tommys.org/pregnancy-information/pregnancy-complications/low-lying-placenta-placenta-praevia

  • By Ummara (not verified) on 28 Mar 2019 - 09:41

    I am 22 weeks pregnant. Yesterday my doctor inform me that i have low lying placenta with a heavly bunch of blood vessels just above internal os. I have light vaginal bleeding last month and now experiencing pain in lower belly region. Can you guide me what are the risks . I am very much disturbed. Have 2 previous c sections . Its 3rd pregnancy

  • By Midwife @Tommys on 24 Apr 2019 - 10:20

    Hi
    The following link has information about low lying placenta and associated risks that you may find helpful-
    https://www.tommys.org/pregnancy-information/pregnancy-complications/low-lying-placenta-placenta-praevia
    There is a risk that you may bleed in the second half of pregnancy (sometimes caused by having sex). Bleeding from placenta praevia can be heavy. If you bleed contact your hospital immediately.

    If you have major placenta praevia (the placenta covers the cervix) you may need to stay in hospital after 34 weeks of pregnancy even if you have had no symptoms. There is a small risk that you could bleed suddenly and severely, which may mean that you need an urgent caesarean section. If you are bleeding the baby may need to be delivered.

    As you have already had 2 c-sections, this baby will also be delivered by c-section-the timing of this will be discussed with you by your obstetrician
    Tommy's midwife

  • By Connie (not verified) on 24 Apr 2019 - 22:38

    Hi all
    I have found out I’m 6 weeks pregnant with baby number 5. I have had 3 previous c sections with placenta previa last pregnancy. Not fully covering but had blood matched up being told I could hamorrege at delivery which everything went smoothly. Thank god. Next day consultant visited me on ward and advised me on the amount of scar tissue they had to cut through to get to baby that it would be advisable not to get pregnant again. I’m now really scared that this time il not be so lucky that going to get placenta accelerate or something worse. I’m at my wits end with worry. Has anyone been in this situation.

  • By Ashley (not verified) on 27 Mar 2019 - 07:09

    I am 30 weeks 3 days pregnant. I have an appointment in a few days and at my last appointment my OBGYN said I have placenta previa. I had placenta previa with my first child and I delivered vaginally. My OBGYN also said that my placenta is lower with this baby than it was with my first and she would determine if I needed to have a cesarean section with this one my next appointment. I was just wondering if it seems to soon to determine if I need a cesarean section or not. It really seems early to me.

  • By Ady (not verified) on 24 Mar 2019 - 22:11

    Hello I’m 17 weeks and my doctor just told me that my placenta is low. What’s the chances it will move up? What are things I Can and can’t do? I don’t have any bleeding as of now. What’s some advise you can give me?

  • By Anonymous (not verified) on 24 Mar 2019 - 03:49

    My first scan at week 20 shows that my placenta was posterior high, but at week 37 the second scan shows posterior low lying. Is that possible for the placenta to come down?

  • By Mira (not verified) on 23 Mar 2019 - 13:51

    It was not explain to me what Grade 2 Placenta means. Does anybody here know whether this can progress to Grade 3 or major placenta praevia? If so, what can be the causes/factors?

    Thank you so much

  • By Victoria Clifford (not verified) on 16 Mar 2019 - 11:41

    I have a low lie placenta and started bleeding at 22 +4 . It was fairly light and stayed 24 hours in hospital. A few days later I passed 2 large clots and so stayed at hospital again. 2 weeks later I again had another bleed, but a bit more heavier and as I was 25 + 4 they kept me in 48 hours. I have woken up today with more bleeding, the same as before. I’m just wondering how many bleeds is normal ... can it happen weekly / bi weekly or is it abnormal to bleed this regularly?

  • By Midwife @Tommys on 22 Mar 2019 - 11:08

    Hi Victoria,
    Sorry to hear that you have been having a difficult time in this pregnancy. I am afraid it is difficult to predict, having a low lying placenta can mean that bleeding can happen in pregnancy, its just very important that each time you do bleed you go into hospital even if its happens regularly and everything is ok.
    Best wishes
    Tommy's midwife

  • By worried dad (not verified) on 13 Mar 2019 - 00:28

    hi my girlfriend went to hospital 2 days ago the doctor tried physically to move placenta as its low she now is bleedin a lot is this a big worry r normal

  • By Lesley (not verified) on 24 Feb 2019 - 16:55

    I'm currently 33 weeks pregnant with my 4th. My placenta isn't blocking the cervix but is too close for a vaginal birth (according to my consultant). It's lying in the posterior position. I'm being told I need a c-section at 37 weeks. Sounds too soon to me. Would it be risky to leave until 38 or 39 weeks? All my other pregnancies were normal vaginal birth at 39+ weeks.

  • By Midwife @Tommys on 27 Feb 2019 - 11:15

    Hi Lesly. You can go back to your consultant and ask for their reasons why they suggest a c/s at 37 weeks as there may be a specific reason this has been suggested for you in this pregnancy. Each case is different. So please do make another appt to see your Consultant and ask if the c/s can be a week or two later. You can also speak to your own midwife about this, it could be a hospital policy, so worth checking with both of them. Take care, Tommy's Midwife

  • By Khadijah (not verified) on 21 Feb 2019 - 11:41

    Good evening. Im still confused about that. It says that completely covering the internal os. But i read some post that grade 1 means minor. Can you explain it to me? Thanks

  • By Midwife @Tommys on 22 Feb 2019 - 13:25

    Hi Khadijah,
    You are right, grade one placenta praevia is minor so only partially covering or near to the internal os.
    Best wishes
    Tommy's midwife

  • By Kavita (not verified) on 16 Feb 2019 - 18:46

    I have 31 week ultrasound. The placenta is posterior low lying 1cm away from internal os.

  • By Nirmal (not verified) on 31 Jan 2019 - 16:30

    Diagnosed low anterior placenta 3 cm away from OS at 20week and subsequently now at 40 week another scan reveals same position
    doc is saying everything is normal, however, low lying placenta case , says risk of bleeding will be there at labour , better go for c section. Please advise is.it possible for normal delivery than c section

  • By Midwife @Tommys on 31 Jan 2019 - 16:38

    Hi - Thank you for your message.
    As your Dr has advised as the placenta is not covering the OS, it is possible for a vaginal delivery, but recommend delivery in hospital, rather than a home setting. You should discuss the risks and benefits of the options for birth with your consultant as it is your decision how your baby is birthed.

  • By Jisha (not verified) on 17 Jan 2019 - 12:36

    33 week pregnent. My placenta is 1 cm away from cervix. Baby is standing position. Hb is 9.8 . First baby 8 year old.it wasormal delivry. Can i give viginal birth?

  • By Midwife @Tommys on 17 Jan 2019 - 12:54

    Hi - Thank you for your message.
    If you have been advised that you have a low lying placenta, you should be offered additional scans and monitoring. If at 36 weeks the placenta is still considered low and too close to opening of the cervix you will be advised by consultant/midwife what the options for birth are.

  • By Anonymous (not verified) on 13 Jan 2019 - 08:02

    19 weeks Placenta: Anterior, totally covering os, Grade 1 Baby is breech

    That’s written on my latest ultrasound. I’m a little confused that it says Grade 1 but it is totally covering my cervix. Do I have a good chance of my placenta going up? I’m hoping for a normal delivery. Or even if I need cesarian atleast not with previa. Does previa cause baby to breech? oping for your answers.

  • By Midwife @Tommys on 14 Jan 2019 - 16:32

    Hi, You will have to speak to your obstetrician or midwife, this is confusing as grades 3 and 4 totally cover the os, wheras grades 1 and 2 may move out of the way of the cervix as seen above. I expect you will be scanned again at 34 weeks (unless there is any bleeding before) where you will be able to clarify in time to arrange your home-birth.

  • By Tara Marson (not verified) on 3 Jan 2019 - 21:29

    Hi,
    I have just had my 32 week scan and my placenta is still low lying and is currently 1cm away from my womb. This is my 2nd baby, previously I had an emergency c- section with my little girl as I got strep B during labour and both myself and baby had extremely high heart rate. The doctor has said that it's up to me whether I deliver naturally or have a c- section but there is risk of bleeding. I'm finding it really hard to decide what to do for the best. I am booked in for another scan at 38 weeks to see if it's moved but I don't imagine it will much in that time. Any help or advice would be really appreciated. Thank you very much

  • By Midwife @Tommys on 7 Jan 2019 - 14:55

    Hi Tara, I can only assume that your placenta is far enough away from the cervix for your doctor to consider vaginal delivery to be a safe option. I understand your dilemma, and I think it is reasonable to wait until 38 weeks before making that decision.

  • By Heather (not verified) on 23 Dec 2018 - 09:34

    Hello,

    I am 20 weeks pregnant and at my anomaly scan I was told I have an anterior low lying placenta. I've read all this helpful information about what to look out for regarding bleeding etc, many thanks for that. My question is perhaps a silly one but something worrying me...if the placenta is low lying the baby must naturally rest on it a lot of the time. I was told in my first pregnancy to sleep in my left side because it could be harmful to the baby for it to lie on the placenta since it could cut off it's cord supply. Is this a risk with a low lying placenta? Is there a risk of brain damage or developmental impacts to the baby sitting on the placenta? Many thanks

  • By Midwife @Tommys on 4 Jan 2019 - 16:30

    Dear Heather,
    Please try not to worry, there is not evidence whatsoever that there is any risk to your baby's development and having a low lying placenta. With regards to sleeping on your left hand side, we so advise to sleep on your side but this is not due to the cord as the cord can be anywhere in the uterus and your baby moves around, it is to do with your own blood vessels and the supply to the placenta.
    I hope this reassures you, you should have a scan later in your pregnancy to check that your placenta has moved away from your cervix.
    Best wishes
    Tommy's midwife

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