Placenta previa is a condition in which the placenta lies low in the uterus and partially or completely covers the cervix. The cervix is the opening of the uterus that allows the baby to pass through during delivery. If the placenta blocks this opening, it can interfere with a safe vaginal birth and may cause complications, especially if bleeding occurs.
There are different types of placenta previa:
- Complete previa: The placenta fully covers the cervix.
- Partial previa: The placenta covers part of the cervix.
- Marginal previa: The placenta is near the edge of the cervix but does not cover it.
- Low-lying placenta: The placenta is implanted in the lower part of the uterus, close to but not touching the cervix.
In many cases, placenta previa detected early in pregnancy resolves on its own as the uterus grows and the placenta moves upward. When the condition persists later into the pregnancy, careful monitoring is essential.
What Causes Placenta Previa?
While the exact cause isn’t always clear, several factors may increase your risk of developing placenta previa:
- Previous cesarean delivery
- Previous placenta previa
- Carrying multiples (twins or more)
- Uterine surgery or scarring (including dilation and curettage)
- Smoking during pregnancy
- Advanced maternal age (35 or older)
It’s important to note that placenta previa is not caused by anything you did or didn’t do. It simply means the placenta implanted in a position that now requires additional observation and planning.
How Is Placenta Previa Diagnosed?
Placenta previa is most commonly diagnosed during a routine second-trimester ultrasound, usually around 18 to 20 weeks. If the ultrasound shows the placenta is covering or near the cervix, your provider may schedule additional ultrasounds in the coming weeks to monitor whether the placenta moves upward as the uterus expands.
In many cases, what appears as previa at 20 weeks becomes a non-issue later in pregnancy. However, if the placenta still covers the cervix in the third trimester, it is considered a persistent placenta previa and may require specific care adjustments.
What Are the Symptoms of Placenta Previa?
Many women with placenta previa do not experience symptoms. The condition is often discovered during a routine ultrasound before any warning signs occur.
However, for some patients, placenta previa may cause:
- Spontaneous, painless vaginal bleeding, especially in the second or third trimester
- Bleeding after sexual activity or a pelvic exam
- Mild cramping or uterine contractions
Any vaginal bleeding during pregnancy should be evaluated, especially if you’ve already been diagnosed with placenta previa. Bleeding can occur as the cervix begins to thin or open, placing stress on the blood vessels where the placenta attaches.
If bleeding is heavy or persistent, you should call your provider immediately or go to the nearest emergency room.
Why Does Placenta Previa Matter?
Placenta previa can increase the risk of several complications, particularly later in pregnancy or during delivery. These may include:
- Preterm birth: If heavy bleeding occurs, early delivery may be necessary.
- Hemorrhage: Bleeding can be severe, especially during labor.
- Placenta accreta: This is a condition in which the placenta attaches too deeply into the uterine wall and does not separate easily after delivery. It is more common in women with placenta previa and prior cesarean deliveries.
- Fetal growth concerns: Although uncommon, poor placental positioning can occasionally affect fetal development.
Because of these risks, placenta previa is managed with increased monitoring, activity modification, and delivery planning to ensure the safest outcome for both mother and baby.
How Is Placenta Previa Managed?
Management of placenta previa depends on several factors, including the type of previa, how far along you are in your pregnancy, and whether you’re experiencing any symptoms.
1. Regular Ultrasound Monitoring
We track placental position over time, typically performing follow-up ultrasounds at 28 to 32 weeks, and again if needed closer to your due date. This helps us determine whether the placenta has moved or if the previa persists.
2. Activity Modifications
You may be advised to avoid strenuous activity, heavy lifting, or sexual intercourse to reduce the risk of bleeding. In some cases, pelvic rest (avoiding anything that enters the vagina) may be recommended.
3. Monitoring for Bleeding
If you experience light bleeding, we may recommend observation and more frequent visits. For heavier or recurrent bleeding, hospitalization or early delivery may be necessary.
4. Delivery Planning
If the placenta still covers the cervix at 36 to 37 weeks, a cesarean delivery will likely be scheduled. This is the safest way to deliver when the cervix is blocked. If you have a low-lying placenta and the cervix is clear, vaginal delivery may still be possible.
5. Coordination with Specialists
In some cases, placenta previa occurs alongside other conditions, such as placenta accreta or preeclampsia. We work closely with your full care team, including maternal-fetal medicine specialists, anesthesiologists, and neonatologists, to plan for every possibility.
What Can You Do at Home to Stay Safe?
If you’ve been diagnosed with placenta previa, there are a few things you can do to help reduce risks and support your health:
- Take bleeding seriously. Even light bleeding should be reported. Keep track of how much, how often, and whether it’s increasing.
- Follow your activity guidelines. If your provider has placed you on pelvic rest or limited activity, be sure to follow those instructions.
- Stay hydrated and nourished. Supporting your overall health helps your body manage any added stress.
- Keep your scheduled appointments. Routine imaging and visits are essential to monitor placental position and detect any changes early.
- Know when to seek emergency care. If bleeding is heavy, doesn’t stop, or is accompanied by contractions or dizziness, go to the ER right away.
How We Support Patients With Placenta Previa
At High Risk Pregnancy Center, we understand the anxiety that can come with a placenta previa diagnosis. That’s why we take a proactive, personalized approach to care. Our team is here to monitor you closely, answer your questions, and help you feel confident about your care plan.
We provide:
- Advanced ultrasound imaging for accurate diagnosis
- Frequent monitoring throughout the second and third trimesters
- Early identification of complications
- Delivery planning and coordination
- Emotional support and education
If you’ve been diagnosed with placenta previa or have questions about bleeding or placenta position, schedule an appointment with our team. We’ll help you understand your condition, monitor your progress, and plan for a safe, healthy delivery.
