COMPLICATIONS: PLACENTA PREVIA
Pregnancy complications can feel overwhelming the moment your provider mentions them. If you've been told you have placenta previa, or you're reading ahead just in case, here's what you and your partner need to know.
What Is Placenta Previa?
The placenta is your baby's lifeline throughout pregnancy, delivering oxygen and nutrients through the umbilical cord. Normally, it attaches high up on the wall of the uterus, well out of the way of your cervix, the opening that your baby will eventually pass through during labor.
In placenta previa, the placenta implants low in the uterus, either partially or completely covering the cervix. There are a few variations:
Complete (or major) previa — the placenta fully covers the cervical opening
Partial previa — the placenta overlaps part of the cervix
Marginal previa — the edge of the placenta reaches the border of the cervix
The position matters because as your cervix begins to thin and open in preparation for birth, a low-lying placenta can tear and bleed, sometimes significantly.
When Is It Diagnosed?
Most cases of placenta previa are first spotted during a routine mid-pregnancy ultrasound, typically around 18–22 weeks. At this stage, it's actually quite common for the placenta to appear low — roughly 1 in 20 pregnancies show a low-lying placenta at the mid-pregnancy scan. The reassuring news is that the vast majority of these resolve on their own. As your uterus grows, the placenta effectively "moves" upward relative to the cervix, and by 32–36 weeks most low-lying placentas are no longer a concern.
If a low-lying placenta is found at your 20-week scan, your provider will schedule a follow-up ultrasound, usually a transvaginal ultrasound (which gives a clearer picture of the cervix) at around 32 weeks, and again at 36 weeks if still present.
True, persistent placenta previa — where the placenta remains over the cervix in the third trimester — affects approximately 1 in 200 pregnancies.
Risk Factors
Some factors make placenta previa more likely:
Previous caesarean section or uterine surgery (scar tissue affects where the placenta implants)
Multiple prior pregnancies
Carrying multiples (twins, triplets)
Smoking
Maternal age over 35
Assisted reproductive technology (IVF)
Having risk factors doesn't mean placenta previa will occur.
What Are the Signs?
For many people, placenta previa is completely symptom-free and discovered only on ultrasound. When symptoms do occur, the most common is:
Painless, bright-red vaginal bleeding, usually in the second or third trimester.
This is sometimes called a "warning bleed." It can range from light spotting to heavy bleeding, and it can stop and restart. If you experience any vaginal bleeding during pregnancy, even if it stops and you feel fine, contact your midwife or doctor the same day, or go to your nearest maternity unit if the bleeding is heavy or you feel unwell.
Unlike some other causes of pregnancy bleeding, the bleeding in placenta previa is typically not accompanied by abdominal pain or contractions. That painlessness is actually a distinguishing feature your care team will consider.
Management: What to Expect
The management of placenta previa depends on several things: how much of the cervix is covered, whether you've had any bleeding, how far along you are, and your overall health. Here's what the journey typically looks like.
If You Have No Bleeding (Asymptomatic)
You'll be monitored closely with repeat ultrasounds, but many people with low-lying placentas continue to have uncomplicated pregnancies. Your care team will advise on:
Pelvic rest: avoiding vaginal intercourse and internal examinations until your placenta's position is confirmed safe
Reducing strenuous activity, depending on severity
Knowing your nearest maternity unit in case of sudden bleeding
If You Have Bleeding
A bleed, even a light one, usually means a trip to hospital for monitoring. Your team will assess the bleeding, check your baby's heart rate, and decide whether you can go home or need to stay in.
Some people with recurrent bleeding are advised to stay in hospital as their due date approaches, particularly if they live far from obstetric care. This is a precaution, not a sign that something has gone wrong.
If bleeding is heavy, or if you or your baby show signs of distress, your team may recommend early delivery.
Anemia and Blood Preparation
Repeated bleeding can lead to iron-deficiency anemia. Your provider will monitor your iron levels and may recommend supplementation. Blood typing and cross-matching may also be done, not because a transfusion is expected, but so everything is prepared just in case.
Delivery: Understanding Your Options
This is the part that affects your birth plan most directly.
Complete placenta previa means a planned caesarean section. A vaginal birth is not possible when the placenta fully covers the cervix, and know attempting labor would cause dangerous bleeding. Your care team will discuss the timing with you, but planned c-sections for placenta previa are typically scheduled between 36 and 37 weeks, sometimes earlier if there's been significant bleeding.
For marginal or partial previa, the decision depends on exactly how close the placenta is to the cervix. Your doctor will review your final ultrasound measurements and guide you through the options.
A Note on Placenta Accreta Spectrum
When someone has had a previous caesarean and also has placenta previa, there is an increased risk of placenta accreta — where the placenta grows too deeply into the uterine wall. This is a more complex condition that requires specialist care and careful surgical planning. Your provider will screen for this if it's relevant to your history.
The Emotional Side
Finding out your placenta is low can be frightening, especially if it comes after weeks of an otherwise smooth pregnancy. It's okay to feel anxious, to grieve a birth plan you'd imagined, or to feel overwhelmed by the uncertainty of not knowing whether the placenta will move.
What can help:
Ask your care team specific questions. "What percentage of the cervix is covered?" "What does this mean for my delivery plan right now?" Concrete information often feels better than vague reassurance.
Talk to your partner. This affects both of you. If your partner is in the dark about what's happening medically, that gap tends to make anxiety worse for everyone. Bring them to appointments, share what you learn here, and keep the conversation open.
Know that many cases resolve. The majority of low-lying placentas identified at 20 weeks move up on their own. Monitoring exists precisely to track this.
Give yourself permission to prepare for a caesarean without feeling like you've failed. A planned caesarean for placenta previa is a deliberate, safe choice, one that prioritizes both your life and your baby's.
What to Watch For
Contact your maternity unit immediately if you experience:
Any vaginal bleeding, no matter how light
Heavy bleeding
Bleeding accompanied by contractions or abdominal pain
Signs of shock: dizziness, rapid heartbeat, feeling faint
Trust your instincts. If something feels wrong, get checked.
The Bottom Line
Placenta previa is manageable with the right care and monitoring. Most early diagnoses resolve before the third trimester. For those where it persists, a well-planned c-section allows for a safe delivery for both parent and baby. The key is staying informed, attending your follow-up scans, knowing the symptoms to look out for, and having open conversations with your care team throughout.
The content presented on Labour the App (whether text, graphics, images, or other material) is provided “as is” and is offered for informational purposes only. The content provided on the App is not intended to be a substitute for professional medical advice, diagnosis, or treatment. You should always seek the advice of your physician or other qualified health provider. For more information, please refer to our Medical Disclaimer and to our Terms of Use.