Placenta previa is a pregnancy condition in which the placenta totally or partially blocks the uterine entrance (cervix).
During pregnancy, an organ called the placenta grows within the uterine. It functions to supply oxygen and sustenance to the infant as well as to eliminate waste. The umbilical cord links the placenta to your baby. The placenta is usually linked to the top or side of the uterine inner wall.
The placenta attaches lower in the uterus in placenta previa. As a result, some of the placental tissue covers the cervix. It can cause bleeding throughout pregnancy, as well as during and after delivery.
Changes in the uterus and placenta during pregnancy may cause the condition to resolve itself. If not, the infant is delivered through cesarean section (C-section).
WHAT ARE THE TYPES OF PLACENTA PREVIA?
The different forms of placenta previa are determined by how much of the cervix is covered by the placenta. The following are examples of placenta previa:
- Complete previa: The placenta fully covers the cervical hole (where the cervix enters the uterus).
- Partial previa: The placenta covers a portion of the cervical opening.
- Marginal previa: The placenta stretches to the cervix's border (close by but not covering it)
During pregnancy, the location of the placenta frequently shifts. As a result, while you may be labeled with one kind, your diagnosis is likely to change as the pregnancy proceeds and the placenta migrates higher with the developing uterus and fetus. In fact, in one study of over 1,200 instances of placenta previa, all but 1.6 percent cleared before birth.
The placenta is less likely to migrate fully off the cervical opening if you have a complete previa than if you have a partial or marginal previa. Furthermore, the later in the pregnancy this issue occurs, the less probable it is to resolve before birth.
WHAT ARE THE SYMPTOMS OF PLACENTA PREVIA?
After 20 weeks of pregnancy, the predominant symptom of placenta previa is bright red vaginal bleeding that is typically painless. Spotting can occur before to an incident involving higher blood loss.
Prelabor uterine contractions that induce discomfort may produce bleeding. Sex or a medical examination may also cause the bleeding. Some women may not experience bleeding until they go into delivery. Often, there is no obvious cause of the bleeding.
WHAT ARE THE CAUSES OF PLACENTA PREVIA?
It is uncertain what causes placenta previa.
WHAT ARE THE RISK FACTORS FOR PLACENTA PREVIA?
Previa of the placenta is more frequent in women who:
- Have had a child
- Have a prior C-section delivery
- Are bearing several fetuses
- Are 35 years old or older
- Have uterine scarring from a prior operation or procedure
- Had a previous pregnancy, that resulted in placenta previa
- Are pregnant after undergoing infertility treatment with assisted reproductive technology (ART)
- Smoke
- Make use of cocaine.
WHAT ARE THE COMPLICATIONS OF PLACENTA PREVIA?
Your health care provider will monitor you and your baby if you have placenta previa to prevent the risk of these major complications:
- Bleeding: Severe, potentially fatal vaginal bleeding (hemorrhage) can occur during pregnancy, labor, delivery, or in the initial few hours following birth.
- Premature birth: Severe bleeding may need an emergency C-section before your baby is fully developed.
- Placenta accreta spectrum: Placenta previa is linked to a range of disorders known as the placenta accreta spectrum. The placenta develops into or through the uterine wall in certain cases. A placenta accreta increases the risk of bleeding throughout pregnancy, as well as during and after delivery.
HOW IS PLACENTA PREVIA DIAGNOSED?
Ultrasound is used to determine placenta previa, either at a regular prenatal checkup or after an episode of vaginal bleeding. The majority of instances of placenta previa are discovered during a second-trimester ultrasound.
An ultrasound instrument on your belly may be used to make the first diagnosis. A transvaginal ultrasound, which employs a wand-like instrument put into your vagina, may also be required for more precise pictures. Your clinician will carefully position the device so that it does not disturb the placenta or cause bleeding.
WHAT ARE THE TREATMENTS FOR PLACENTA PREVIA?
If placenta previa is discovered during a normal exam, you will almost certainly need more regular ultrasounds to monitor any changes in the placenta.
Many women with placenta previa who are discovered early in their pregnancies find that the problem cures on its own. The distance between the cervix and the placenta may expand as the uterus develops. In addition, the direction of growth of the placenta in the uterus may be higher, and the borders of placental tissue near the cervix may diminish.
If the placenta previa dissolves, you may be able to schedule a vaginal birth. If it does not resolve, you will schedule a C-section.
Bleeding treatment
After 20 weeks, vaginal bleeding is considered a medical emergency. You may be admitted to the labor and delivery unit of the hospital. Your baby and you will be watched, and you may require a blood transfusion to replace any lost blood.
If you are 36 weeks pregnant, the baby will most likely be delivered through C-section. If you suffer excessive blood loss or there is a risk to your or the baby's health, an emergency C-section may be required before 36 weeks.
If this is your first episode of bleeding, and the bleeding has stopped for at least 48 hours, you may be discharged from the hospital. If you continue to experience episodes of heavy bleeding, your doctor may advise you to stay in the hospital.
Treatment with no bleeding
When there is no bleeding, the objective of therapy is to reduce the risk of future bleeding and get you as near to your due date as feasible. Your doctor will most likely advise you to avoid the following:
- Sexual intercourse or sexual activity that has the potential to result in orgasm
- Moderate to vigorous physical activity
- Heavy or moderate lifting
- Standing for extended durations
If you are discharged from the hospital after a first episode of bleeding, you will be required to follow these same measures to reduce the chance of a second episode.
If you have vaginal bleeding or contractions, you should seek emergency medical attention. Your health care practitioner may inquire whether you have access to transportation to a local hospital.
CONCLUSION
Placenta previa can be extremely distressing for everyone concerned. Fortunately, most of the time, the problem will resolve without the need for a premature delivery and/or cesarean surgery. Even if your placenta remains in place, you are quite likely to have a safe birth with proper prenatal care.