placenta praevia

Placenta Praevia: A Condition of Pregnancy

Placenta praevia is a condition that occurs during pregnancy when the placenta implants in the lower part of the uterus, partly or completely obstructing the cervical outlet. This can cause vaginal bleeding during pregnancy and labor.

• Definition: Placenta praevia is a type of placenta previa where the placenta attaches inside the uterus but in a position near or over the cervical opening [1].
• Symptoms: Symptoms include vaginal bleeding in the second half of pregnancy [1].
• Types: There are different forms of placenta praevia, including:
  • Marginal: The placenta is next to the cervix but does not cover the opening.
  • Major: The placenta covers a portion or all of the cervical opening.

Causes and Risks

Placenta praevia can cause bleeding late in pregnancy. This means after about 20 weeks [14]. When the placenta is attached close to the opening of the uterus (cervix) or covers the cervix, it is called placenta previa [15].

• Risk of Bleeding: Placenta praevia may cause painless bleeding that suddenly begins after 20 weeks of pregnancy. The bleeding may become profuse.
• Delivery Method: The baby is usually delivered by cesarean.

References

[1] - Refers to context #12 [14] - Refers to context #14 [15] - Refers to context #15

Common Signs and Symptoms of Placenta Praevia

Placenta praevia, also known as placenta previa, is a condition where the placenta partially or completely covers the cervix. The most common symptoms of this condition are:

• Painless vaginal bleeding: This is the primary sign of placenta praevia after 20 weeks of pregnancy. The bleeding can be heavy and may occur suddenly.
• Mild to severe cramping: Some women may experience mild or severe contractions in their abdomen, back, or belly.
• Premature contractions: Women with placenta praevia are at a higher risk of delivering prematurely before 37 weeks of pregnancy.

Other Possible Symptoms

While not as common, other possible symptoms of placenta praevia include:

• Bleeding during the third trimester: This can be a sign that the placenta is covering the cervix.
• Premature rupture of membranes: In some cases, the condition can cause the membranes to rupture prematurely.

Important Note

It's essential to note that placenta praevia is often asymptomatic and may only be discovered incidentally on routine second-trimester ultrasonography. If you experience any symptoms or have concerns about your pregnancy, it's crucial to consult with a healthcare provider for proper evaluation and care.

References:

• [1] Sudden, painless vaginal bleeding; bleeding may be heavy, sometimes resulting in hemorrhagic shock.
• [5] Symptoms of placenta previa typically manifests as sudden, painless vaginal bleeding; bleeding may be heavy, sometimes resulting in hemorrhagic shock.
• [8] The main symptom of placenta previa is sudden bleeding from the vagina. Some women also have cramps.
• [10] Placenta previa can cause bleeding late in pregnancy. This means after about 20 weeks.
• [11] Signs and symptoms may vary, but the most common symptom is painless bleeding during the third trimester.
• [13] Bleeding occurs at some time in most women with placenta previa, and it is the primary sign after the 20th week during pregnancy.

Placenta previa can be diagnosed through various diagnostic tests, which are essential for confirming the condition and determining the best course of action.

Ultrasound Tests

• Ultrasound is the primary diagnostic test used to confirm placenta previa [5]. It helps doctors determine the location of the placenta and identify any potential complications.
• Transvaginal ultrasonography is considered the gold standard for diagnosing placenta previa, with a sensitivity of 88% and specificity of 99% [6].
• Ultrasound scans can be performed during routine prenatal appointments or after an episode of vaginal bleeding.

Other Diagnostic Tests

• Vaginal ultrasound (or transvaginal ultrasound) involves inserting a wand-like device into the vagina to check the position of the baby, placenta, and cervix [2].
• Transabdominal sonography can also be used to diagnose placenta previa, although it may not provide as accurate results as transvaginal ultrasonography.

Importance of Diagnostic Tests

• Early diagnosis through ultrasound tests is crucial for preventing complications and ensuring a safe delivery.
• Accurate diagnosis helps doctors determine the best course of action, which may involve cesarean delivery or other interventions to ensure the mother's and baby's safety.

In summary, diagnostic tests such as ultrasound scans are essential for diagnosing placenta previa and determining the best course of action. These tests help confirm the condition, identify potential complications, and ensure a safe delivery for both the mother and baby.

Treatment Options for Placenta Praevia

Placenta praevia, a condition where the placenta covers or lies close to the cervix, can be treated in various ways depending on the severity and gestational age. Here are some treatment options:

• Bed rest and limitation of activity: This is often recommended to reduce bleeding and stabilize the pregnancy.
• Tocolytic medications: Medications such as magnesium sulfate or terbutaline (Brethine) may be used to slow down or inhibit labor, depending on the severity of the condition [5].
• Intravenous fluids and blood transfusions: These may be required to manage severe bleeding and maintain maternal stability.
• Cesarean section: In some cases, a C-section is often the best and safest route of delivery if placenta praevia persists until the time of delivery [6].

Conservative Management

In some cases, conservative management may be considered, where the placental tissue is left in situ with arterial ligation and adjuvant methotrexate therapy [7]. However, this approach is not without risks and should only be considered under close medical supervision.

Other Treatment Options

• Medicines to prevent early labor: Medications such as beta adrenergic agonists, calcium channel blockers, magnesium sulfate, oxytocin receptor antagonist, progesterone, prostaglandin inhibitors may be used to manage preterm labor [9].
• Shot of special medication: A shot of a special medication may be given to help pregnancy continue to at least 36 weeks [8].

It's essential to note that the treatment plan will depend on individual circumstances and should only be determined by a qualified healthcare provider.

References:

[5] - Treatment of placenta previa involves bed rest and limitation of activity. Tocolytic medications, intravenous fluids, and blood transfusions may be required depending upon the severity of the condition. [6] - If placenta previa persists until the time of delivery then a C-section is often the best and safest route of ... [7] - Conservative management of placenta previa percreta by leaving placental tissue in situ with arterial ligation and adjuvant methotrexate therapy [8] - A shot of special medication may be given to help pregnancy continue to at least 36 weeks [9] - They include beta adrenergic agonists, calcium channel blockers, magnesium sulfate, oxytocin receptor antagonist, progesterone, prostaglandin inhibitors

The differential diagnosis of placenta praevia, also known as placenta previa, involves a range of conditions that can present with similar symptoms to placenta praevia. These include:

• Abruptio placentae: This is a condition where the placenta separates from the uterus, leading to vaginal bleeding and potentially life-threatening complications for both mother and baby.
• Local cervical lesions (polyps, carcinoma): Growths or tumors on the cervix can cause bleeding and mimic the symptoms of placenta praevia.
• Circumvallate placenta: A rare condition where the placenta grows in a circular shape around the internal os of the cervix, which can be mistaken for placenta previa.
• Vasa previa: This is a condition where fetal blood vessels are exposed and at risk of rupture, leading to vaginal bleeding.
• Focal myometrial contraction: A rare condition where the uterus contracts in a localized area, causing the placenta to appear closer to the internal cervical os than it actually is.

These conditions can be challenging to diagnose, especially if they present with similar symptoms to placenta praevia. However, accurate diagnosis and treatment are crucial to prevent complications and ensure the best possible outcome for both mother and baby.

According to [2], differential diagnoses to consider include abruptio placentae, local cervical lesions (polyps, carcinoma), circumvallate placenta, vasa previa or focal myometrial contraction. These conditions can be diagnosed through a combination of clinical evaluation, ultrasound imaging, and laboratory tests.

In some cases, the diagnosis may require further investigation, such as [5] which mentions that a full bladder, focal myometrial contraction, these can make the placenta appear closer to the internal cervical os than it actually is.