Few words in a pregnancy report cause as much immediate anxiety as placenta previa. Patients who see it written in their scan report often arrive at their next appointment frightened and full of questions. The good news is that placenta previa, particularly when detected early, is a manageable condition. Understanding what it means, why it happens, and how it is monitored makes an enormous difference to how a family navigates the rest of their pregnancy. At Jhansi Diagnostics & Fetal Medicine Centre, Dr Furquan Ahmad, MBBS MD, regularly monitors pregnancies affected by placenta previa and ensures every patient leaves with a clear understanding of their specific situation.
Here is everything you need to know.
What Is Placenta Previa?
The placenta is the organ that develops inside the uterus during pregnancy to supply the baby with oxygen and nutrients through the umbilical cord. In a normal pregnancy, the placenta attaches to the upper part of the uterine wall, well away from the cervix. In placenta previa, the placenta attaches lower in the uterus and either partially or completely covers the cervical opening.
This matters because the cervix is the birth canal’s entrance. A placenta positioned over or near it creates a risk of bleeding during pregnancy and delivery, and in cases where the placenta completely covers the cervix, a vaginal delivery becomes unsafe. The degree to which the placenta covers the cervix determines how the condition is classified and managed.
Placenta previa is classified into two main types. A complete or major placenta previa means the placenta fully covers the internal cervical opening. A partial or minor placenta previa means the placenta lies close to or partially overlaps the cervical opening without covering it entirely. A low-lying placenta, while not technically placenta previa, is a related finding where the placenta is positioned in the lower segment of the uterus but does not reach the cervical opening. All three require monitoring. You can read more about the pregnancy scans used to monitor these conditions on the ultrasound page.
How Common Is It and Why Does It Happen?
Placenta previa affects approximately one in every 200 pregnancies at term. It is more commonly detected earlier in pregnancy, often on the routine anomaly scan at 18 to 20 weeks, and in many of these cases the placenta moves upward as the uterus grows and the condition resolves on its own before delivery. This process is called placental migration and is why an early finding of low-lying placenta or placenta previa does not automatically mean the condition will persist to term.
Several factors increase the likelihood of placenta previa. A previous caesarean section leaves scar tissue on the uterine wall that can affect where the placenta implants in a subsequent pregnancy. Previous uterine surgery, a history of multiple pregnancies, carrying twins or more, advanced maternal age, and smoking are all associated with a higher risk. In some cases there is no identifiable cause.
How Is It Detected?
Placenta previa is most commonly picked up during the anomaly scan at 18 to 20 weeks. This is one of the reasons the anomaly scan is so important as a routine part of antenatal care. Dr Furquan Ahmad assesses placental position as a standard part of every mid-pregnancy scan at Jhansi Diagnostics & Fetal Medicine Centre, measuring the distance between the lower edge of the placenta and the internal cervical opening precisely.
A transvaginal ultrasound is often more accurate than a transabdominal scan for assessing placental position, particularly in the earlier part of pregnancy. It provides a clearer view of the relationship between the placenta and the cervix and gives Dr Furquan Ahmad the precise measurements needed to classify the condition and plan monitoring appropriately. If you have questions about what either type of scan involves, the FAQs page has useful information.
What Are the Symptoms?
The most characteristic symptom of placenta previa is painless vaginal bleeding in the second or third trimester. This bleeding occurs because the lower segment of the uterus begins to thin and stretch as the pregnancy progresses, causing the placenta to bleed where it is attached over the cervix. The bleeding can range from light spotting to heavy bleeding and can occur suddenly without warning.
Not all women with placenta previa experience bleeding before delivery. Some cases are entirely asymptomatic and are only discovered through routine scanning. This is why routine scanning matters so much. A condition that could cause serious complications at delivery is far safer to know about in advance than to discover for the first time during an emergency.
Any vaginal bleeding during pregnancy should be reported to a doctor immediately. If you have been diagnosed with placenta previa and experience bleeding, seek medical attention the same day without waiting for a scheduled appointment.
How Is Placenta Previa Monitored?
Once placenta previa is identified, the monitoring plan depends on the type, the gestational age at diagnosis, and whether the patient has experienced any bleeding. Dr Furquan Ahmad tailors the monitoring schedule at Jhansi Diagnostics & Fetal Medicine Centre to each patient’s specific situation rather than applying a one-size-fits-all approach.
For a low-lying placenta detected at the anomaly scan, a follow-up scan is typically scheduled at 32 weeks to check whether the placenta has migrated upward. In many cases it has, and no further specific monitoring is needed beyond standard antenatal care.
For a confirmed placenta previa at the anomaly scan, follow-up scans are scheduled more frequently, usually at 28 to 32 weeks and again at 36 weeks, to reassess the placental position and plan for delivery. Dr Furquan Ahmad uses transvaginal ultrasound at these follow-up appointments for the most accurate assessment of placental position relative to the cervix.
If the placenta previa persists to 36 weeks and remains major, a planned caesarean section is typically recommended before the onset of labour. Allowing labour to begin with a complete placenta previa in place carries a significant risk of life-threatening bleeding. Planning the delivery in advance, at the right gestational age and in the right setting, is the safest approach for both mother and baby.
Women with placenta previa are also advised to avoid sexual intercourse and strenuous physical activity during pregnancy, as these can trigger bleeding. Any plan for physical activity or travel should be discussed with the obstetric team. The full range of pregnancy monitoring services available at Jhansi Diagnostics & Fetal Medicine Centre is outlined on the our services page.
Placenta Accreta: When Monitoring Reveals More
In some cases, particularly in women with a previous caesarean section and an anterior low-lying placenta, Dr Furquan Ahmad also screens for placenta accreta spectrum, a condition where the placenta implants too deeply into the uterine wall. This is a more serious complication than placenta previa alone and requires specialist obstetric planning for delivery.
Colour Doppler ultrasound is used to assess the vascularity of the placental implantation site and look for signs of abnormally deep attachment. Identifying this early allows the obstetric team to plan delivery at a centre equipped to manage the associated surgical complexity. This is another example of why detailed fetal medicine scanning by an experienced specialist matters far beyond what a routine antenatal scan can provide.
What Should You Do If You Have Been Diagnosed?
If your scan report mentions a low-lying placenta, placenta previa, or any uncertainty about placental position, the first step is to book a follow-up scan with a fetal medicine specialist who can assess the finding in detail and give you a clear monitoring plan. A finding on a routine scan is the starting point, not the final word.
At Jhansi Diagnostics & Fetal Medicine Centre, Dr Furquan Ahmad sees patients referred for placental assessment from across Jhansi and Bundelkhand. Appointments can be booked through the booking appointment page. For any questions before your visit, the team is available through the contact us page.
Placenta previa is a condition that deserves careful monitoring and specialist input. With the right plan in place, the vast majority of women with this diagnosis go on to deliver safely.
