Low-Lying Placenta in Ajax: Understanding the Follow-Up Scan

It is often a single line near the end of a mid-pregnancy ultrasound report: placenta low-lying, recommend follow-up. Sometimes a provider mentions it in passing; sometimes you read it yourself in a patient portal before anyone has explained it. Either way, the phrase tends to linger, and searching for it late at night rarely helps.

The short version is reassuring for many people. A placenta that sits low in the middle of pregnancy frequently appears to move upward as the pregnancy continues, and the follow-up scan exists to check whether that has happened. The longer version, which this article covers, explains what “low-lying” actually describes, why the picture tends to change, what the follow-up scan involves, and which symptoms should never wait for an appointment.

This is general information for parents in Ajax, Pickering, Whitby and nearby communities. Your own provider knows your history and is the right person to explain what the finding means for you.

Bleeding in pregnancy: what to do first

Because a low placenta can be linked with bleeding later in pregnancy, this needs to be said clearly and early.

If you have heavy vaginal bleeding, bleeding with pain or cramping, regular contractions, dizziness or fainting, call 911 or go to the nearest hospital emergency department or labour and delivery unit right away.

For any amount of bleeding when you have been told your placenta is low, contact your provider or the hospital where you plan to give birth promptly, even if it seems light and has stopped. They will tell you whether to come in.

A community ultrasound clinic is not the place to go for bleeding in pregnancy. Our appointments are scheduled scans, not urgent assessments, and the hospital team is set up to monitor you and your baby.

What the placenta does, and where it can attach

The placenta is the organ that grows during pregnancy to connect you and your baby. It attaches to the inner wall of the uterus and passes oxygen and nutrients through the umbilical cord, while carrying waste products away.

It can attach almost anywhere: high on the front wall, along the back, toward the top of the uterus (often called fundal), or to one side. Most of these positions make little practical difference to the pregnancy. Front-wall placentas, for instance, can muffle movements a little, but they are common and usually considered a normal variation.

The position that matters most is how close the lower edge of the placenta sits to the cervix, the opening at the bottom of the uterus that the baby passes through during a vaginal birth.

Low-lying versus covering the cervix

When a report describes the placenta’s relationship to the cervix, it generally falls into one of these categories:

• Clear of the cervix. The lower edge is well away from the opening. This is the most common finding and usually needs no follow-up for position.
• Low-lying. The lower edge is close to the cervix but does not cover it.
• Covering the cervix. Some or all of the placenta lies over the opening. You may see the term placenta previa used for this situation.

The exact distances used to define these categories, and the wording on reports, can vary between guidelines and practices. Rather than measuring yourself against numbers found online, ask your provider how your result was described and what it means for your care.

Why the placenta often appears to “move”

The placenta does not actually detach and crawl upward. What changes is the uterus around it.

In the second half of pregnancy, the lower part of the uterus stretches and lengthens considerably to make room for the growing baby. As this lower section develops, the distance between the placenta’s edge and the cervix often increases. Many people describe this as the placenta “migrating” or “moving up,” which is a handy way to picture it even though the attachment itself stays put.

There is a second reason the picture can change. Earlier in pregnancy, the view of the lower uterus can be affected by a full or empty bladder, a contraction of the uterine muscle, or the baby’s position. Any of these can make the placenta appear closer to the cervix than it really is. A later scan, under different conditions, may give a clearer measurement.

This is why a low placenta found at the anatomy scan is usually treated as something to recheck, not as a final answer. Our article on the mid-pregnancy anatomy scan describes where placental position fits among everything else that scan looks at.

When the follow-up usually happens

The timing of the repeat scan is decided by your provider, and it varies with what was seen and with your history. In many pregnancies the recheck is arranged in the third trimester, once the lower uterus has had time to develop. Some providers ask for it earlier, particularly if the placenta appeared to cover the cervix or if there has been any bleeding.

The follow-up may be a scan booked specifically to look at the placenta, or it may be combined with a third-trimester scan that also checks the baby’s growth, fluid and position. Our guide to third-trimester growth scans covers what else may be measured at a later visit.

What happens at the follow-up scan

A placental follow-up is usually a focused exam. The sonographer is mainly interested in the lower part of the uterus and the relationship between the placenta and the cervix.

The abdominal view

Most obstetrical scans start with the probe on your belly, using warm gel. The sonographer will find the placenta, trace its edges and look toward the cervix. Depending on the instructions you were given, your bladder may need to be partly full or empty for this part. Follow the preparation you receive when you book, and call to confirm if anything is unclear.

Whether an internal view is used

The cervix sits deep in the pelvis, and the clearest measurement of the distance between it and the placenta can sometimes be obtained with a transvaginal (internal) ultrasound. This uses a slim probe, covered and lubricated, placed a short way into the vagina. It is generally considered a safe way to look at the cervix in pregnancy, including when the placenta is low.

Whether an internal view is part of your appointment depends on what your provider has requested and on the clinic’s protocol, so it is worth asking your provider and calling the clinic to confirm ahead of time. If one is suggested on the day, the sonographer will explain why, and you can ask questions, take a moment to think it over, or decline. Your comfort and consent matter.

How long it takes

A focused placental check is often shorter than an anatomy scan, but if it is combined with growth measurements it will take longer. The baby’s position can also affect how quickly the views can be obtained.

What the result might lead to

The sonographer records images and measurements, and a report goes to the provider who ordered the scan. They will explain the result and what it means. Broadly, outcomes fall into a few groups:

1. The placenta is now clear of the cervix. For many people, this is the end of the matter as far as placental position goes, and routine care continues.
2. The placenta is still low but not covering the cervix. Your provider may plan another scan closer to the due date and talk with you about what this means for birth planning.
3. The placenta covers the cervix. Your provider will discuss closer monitoring and plan the birth with you. This conversation often involves the hospital team where you are booked to deliver.

Decisions about activity, travel, intimacy, work, and how and where to give birth belong to your provider. Advice varies from person to person, so please do not rely on general rules online. If you have been given specific instructions, follow those.

Questions to bring to your provider

Writing a few questions down before your next prenatal appointment can make the conversation easier:

• How was my placenta described on the report, and how far from the cervix was it?
• When will the follow-up scan be, and what preparation do I need?
• Might an internal ultrasound be part of the follow-up?
• Is there anything you would like me to avoid until we know more?
• Who should I call, and where should I go, if I have any bleeding?
• If the placenta stays low, how could that affect my birth plan?

Frequently asked questions

Did I cause this?

There is nothing you did to place the placenta where it attached. Its position is set early in pregnancy and is not caused by exercise, lifting, diet or sleep position.

Will I feel anything different?

Many people with a low-lying placenta have no symptoms at all. That is why it is usually found on ultrasound rather than because of how someone feels. Bleeding, if it happens, is the symptom to act on, as described above.

Can I still have a 3D/4D keepsake scan?

A keepsake scan is separate from medical care and does not replace your follow-up. If you are considering one, let your provider know about the placental finding and ask whether they have any concerns, and mention it to the clinic when you call.

Can my partner come to the follow-up?

Support people are often welcome at obstetrical scans, but policies can depend on the type of exam. Call the clinic to confirm before your visit.

Booking your follow-up ultrasound in Ajax

Rossland Diagnostic Clinic provides obstetrical ultrasound at Unit 102, 300 Rossland Road East, Ajax, with free parking and a ground-floor entrance that is easy to manage late in pregnancy. We are open Monday to Friday from 9:00am to 5:00pm and Saturday from 8:00am to 3:30pm. Please bring your health card and requisition.

When your provider has requested a follow-up scan, call 905-426-3111 or request an appointment, and our team will confirm the preparation for your exam.