7 Critical Placenta Previa Symptoms Every Pregnant Woman Should Know

Placenta previa is a serious pregnancy complication that occurs when the placenta partially or completely covers the cervix, the opening of the uterus. This condition affects approximately 1 in 200 pregnancies and can lead to significant bleeding during pregnancy and delivery. Recognizing the symptoms early is crucial for the health and safety of both mother and baby.

Understanding the warning signs of placenta previa can help pregnant women seek timely medical care and prevent potential complications. While some women may not experience any symptoms, others may notice distinct changes that require immediate attention. This comprehensive guide explores the most common symptoms of placenta previa, helping you identify when to contact your healthcare provider.

1. Painless Bright Red Vaginal Bleeding

The most characteristic symptom of placenta previa is sudden, painless vaginal bleeding that typically appears bright red in color. This bleeding usually occurs during the second or third trimester of pregnancy, most commonly after the 20th week.

The bleeding happens because as the lower part of the uterus stretches and thins during the later stages of pregnancy, it can cause the blood vessels connecting the placenta to separate, resulting in bleeding. What makes this symptom particularly distinctive is the absence of pain, which differentiates it from other causes of pregnancy bleeding such as placental abruption.

The amount of bleeding can vary significantly:

• Some women experience light spotting
• Others may have heavy bleeding that stops on its own
• Bleeding episodes may be recurrent, stopping and starting again days or weeks later
• Some cases involve continuous bleeding requiring immediate medical intervention

Any vaginal bleeding during pregnancy should be reported to your healthcare provider immediately, regardless of the amount.

2. Recurrent Bleeding Episodes

Women with placenta previa often experience multiple episodes of bleeding throughout their pregnancy rather than a single incident. These recurrent bleeding episodes are a hallmark of the condition and can be unpredictable in timing and severity.

The pattern typically includes:

• Initial bleeding that stops spontaneously without intervention
• A period of normalcy lasting days to weeks
• Sudden resumption of bleeding without warning or trigger
• Progressive increase in frequency or severity as pregnancy advances

Each bleeding episode can cause significant anxiety and may require hospitalization for monitoring. The unpredictable nature of these episodes makes it essential for women diagnosed with placenta previa to have a clear emergency plan and maintain close communication with their healthcare team.

3. Bleeding After Physical Activity or Intercourse

Women with placenta previa may notice bleeding that occurs specifically after certain activities. Physical exertion, sexual intercourse, or even routine pelvic examinations can trigger bleeding episodes in women with this condition.

Common triggers include:

• Sexual intercourse, which is why doctors typically advise avoiding it when placenta previa is diagnosed
• Strenuous physical activities or heavy lifting
• Vaginal examinations or cervical checks
• Intense exercise or prolonged standing

This occurs because these activities can cause pressure or minor trauma to the cervical area where the placenta is abnormally positioned. Healthcare providers usually recommend pelvic rest, which means avoiding anything that could put pressure on or enter the cervix, including tampons, douches, and sexual activity.

4. Uterine Contractions or Cramping

While painless bleeding is the most common symptom, some women with placenta previa may experience uterine contractions or mild cramping, particularly if bleeding is significant or if the condition occurs alongside other complications.

These contractions may present as:

• Mild, irregular cramping sensations in the lower abdomen
• Tightening or hardening of the uterus
• Regular contractions that may signal preterm labor
• Discomfort that differs from typical round ligament pain

It’s important to note that severe abdominal pain is not typical of placenta previa alone. If you experience severe pain along with bleeding, this could indicate a different or additional complication such as placental abruption, and you should seek emergency medical care immediately.

5. Abnormal Baby Position

Placenta previa can sometimes cause the baby to be in an abnormal position in the uterus. Because the placenta is blocking or partially blocking the cervix, the baby may not be able to settle into the normal head-down position as the due date approaches.

Positional abnormalities associated with placenta previa include:

• Breech position (baby’s bottom or feet pointing downward)
• Transverse lie (baby lying horizontally across the uterus)
• Oblique lie (baby positioned at an angle)

While the abnormal position itself doesn’t cause symptoms the mother can feel, it’s typically discovered during routine ultrasound examinations or when your healthcare provider palpates your abdomen to check the baby’s position. This finding often raises the suspicion of placenta previa if it hasn’t already been diagnosed, prompting further investigation with ultrasound imaging.

6. Premature Labor Signs

Women with placenta previa have an increased risk of premature labor, which can present with its own set of symptoms. These symptoms may occur alongside or independent of bleeding episodes.

Warning signs of preterm labor include:

• Regular contractions that occur every 10 minutes or more frequently
• Lower back pain that is constant or comes in waves
• Pelvic pressure feeling like the baby is pushing down
• Abdominal cramping with or without diarrhea
• Increase in vaginal discharge or change in discharge type
• Fluid leaking from the vagina

Premature labor in the context of placenta previa is particularly concerning because it can lead to severe bleeding during delivery. If you experience any signs of premature labor, contact your healthcare provider immediately or go to the hospital for evaluation.

7. Absence of Symptoms (Silent Placenta Previa)

Interestingly, many cases of placenta previa are completely asymptomatic, meaning the mother experiences no noticeable symptoms at all. This is often referred to as “silent” placenta previa and is typically discovered during routine prenatal ultrasound examinations.

Key points about asymptomatic placenta previa:

• The condition is identified incidentally during the standard 20-week anatomy scan
• Low-lying placenta detected early in pregnancy often resolves on its own as the uterus grows
• Even without symptoms, the condition requires careful monitoring and follow-up ultrasounds
• Absence of bleeding doesn’t mean the condition is less serious or won’t require intervention at delivery

This highlights the importance of attending all scheduled prenatal appointments and ultrasounds. Many women with placenta previa never experience bleeding but still require a cesarean delivery to ensure safe birth. Regular monitoring allows your healthcare team to track the placenta’s position and plan appropriately for delivery.

Main Causes and Risk Factors

While the exact cause of placenta previa isn’t always known, several factors can increase a woman’s risk of developing this condition. Understanding these risk factors can help identify women who may need more careful monitoring during pregnancy.

Previous Uterine Surgery

Women who have had previous cesarean sections, uterine surgery, or procedures involving the uterine lining have a significantly higher risk of placenta previa. Scarring from these procedures can affect where the placenta implants during subsequent pregnancies.

Multiple Pregnancies

The risk of placenta previa increases with each pregnancy. Women who have had several children are more likely to develop this condition compared to first-time mothers.

Previous Placenta Previa

Having placenta previa in a previous pregnancy increases the likelihood of it occurring again in future pregnancies, with recurrence rates ranging from 4% to 8%.

Multiple Gestation

Carrying twins, triplets, or more babies increases the risk of placenta previa because the placenta needs to be larger to support multiple babies, increasing the chance it will reach and cover the cervix.

Maternal Age

Women over the age of 35 have a higher risk of developing placenta previa compared to younger women. The risk continues to increase with advancing maternal age.

Smoking and Substance Use

Cigarette smoking and cocaine use during pregnancy are associated with an increased risk of placenta previa. These substances can affect placental development and implantation.

Abnormal Uterine Shape

Uterine abnormalities or fibroids can affect where the placenta implants and increase the risk of placenta previa.

Assisted Reproductive Technology

Pregnancies achieved through in vitro fertilization (IVF) or other assisted reproductive technologies have a slightly higher incidence of placenta previa.

Frequently Asked Questions

Can placenta previa resolve on its own?

Yes, many cases of placenta previa diagnosed early in pregnancy (especially before 20 weeks) resolve on their own as the uterus grows and expands. This is called “placental migration,” though the placenta doesn’t actually move but rather the lower uterine segment grows and stretches, making it appear that the placenta has moved away from the cervix. However, placenta previa diagnosed later in pregnancy, particularly in the third trimester, is less likely to resolve.

How is placenta previa diagnosed?

Placenta previa is diagnosed through ultrasound examination. If you experience bleeding during pregnancy, your healthcare provider will perform an ultrasound to determine the placenta’s location. Transvaginal ultrasound is the most accurate method for diagnosing placenta previa, though it’s performed very carefully to avoid causing additional bleeding.

Is bleeding from placenta previa always heavy?

No, bleeding from placenta previa can range from light spotting to heavy hemorrhage. Some women experience only minimal spotting, while others may have life-threatening bleeding. The amount of bleeding doesn’t necessarily correlate with the severity of the placenta previa or predict future bleeding episodes.

Can I have a vaginal delivery with placenta previa?

It depends on the type and severity of placenta previa. Complete placenta previa (where the placenta completely covers the cervix) requires cesarean delivery. Marginal placenta previa (where the placenta is near but not covering the cervix) may allow for vaginal delivery in some cases, but this decision is made carefully by your healthcare provider based on various factors including the exact placental position, bleeding history, and fetal position.

What should I do if I start bleeding during pregnancy?

Any vaginal bleeding during pregnancy requires immediate medical attention. Call your healthcare provider right away or go to the emergency room. Do not use tampons, have sexual intercourse, or perform vaginal examinations yourself. Lie down and rest while waiting for medical care. If bleeding is heavy or accompanied by severe pain, dizziness, or weakness, call emergency services immediately.

Does placenta previa affect the baby?

Placenta previa primarily poses risks to the mother through bleeding, but it can also affect the baby. Risks to the baby include premature birth (if early delivery becomes necessary due to bleeding), low birth weight, and complications from maternal blood loss. However, with proper monitoring and management, most babies born to mothers with placenta previa do well.

Will I need bed rest if diagnosed with placenta previa?

This depends on the severity of your condition and whether you’ve had bleeding episodes. Some women with placenta previa require strict bed rest and possibly hospitalization, especially after bleeding episodes. Others with minor or asymptomatic placenta previa may only need to avoid strenuous activities and sexual intercourse. Your healthcare provider will give you specific activity restrictions based on your individual situation.

How often will I need ultrasounds if I have placenta previa?

Women diagnosed with placenta previa typically need more frequent ultrasounds than those with normal placental placement. You may have ultrasounds every few weeks to monitor the placenta’s position and check for placental migration. The exact frequency depends on when the condition was diagnosed, the severity, and whether you’ve experienced bleeding.

References:

• Mayo Clinic – Placenta Previa
• American College of Obstetricians and Gynecologists – Bleeding During Pregnancy
• National Center for Biotechnology Information – Placenta Previa
• NHS – Placenta Praevia
• Johns Hopkins Medicine – Placenta Previa