The placenta is a highly specialized organ that develops during pregnancy. Anterior placenta is usually a harmless condition where this organ attaches to the front of the uterus (womb) instead of the posterior area.
The placenta helps supply oxygen and nutrients to the developing fetus and carries away waste materials. In addition, it protects the baby from infections and produces hormones for the smooth progress of pregnancy and childbirth (1).
Read on to know more about anterior placenta, including whether it affects the baby’s growth or your labor and delivery. Also, learn about some signs that indicate you should consult your doctor and some home care measures to follow.
What Is Anterior Placenta?
An anterior placenta is when the placenta attaches itself to the front of the uterus, close to the abdominal wall.
While the placenta can attach itself anywhere in the uterus, it usually develops in the posterior (back) side, close to the spine. In the anterior placental position, most of the baby’s movements are masked by the placenta and may not be detected.
An anterior placenta is a rare phenomenon and is more likely to happen if you had a cesarean earlier (2).
When Will You Know If You Have An Anterior Placenta?
The doctor checks the placental position in the 20th-week scan, which is also referred to as the ‘anomaly scan’ (3). The placental location can be described as:
- Anterior: Implants on the front of the uterine wall
- Posterior: Implants on the back of the uterine wall
- Fundal: Attaches to the top of the uterine wall
- Right or left lateral: Implants on the right or left side of the uterus (4)
- Placenta previa: The placenta is positioned over the cervix (the opening of the uterus).
Does Anterior Placenta Affect Your Pregnancy?
An anterior placenta is not a cause for concern, but it might make certain things difficult.
- Fetal heartbeat: Usually, you would be able to first hear the baby’s heartbeat between the 10th and the 12th week of pregnancy (5). It may be detected either by a hand-held DoppleriXA form of ultrasound that is used to examine blood flow or a fetoscopeiXA specially developed stethoscope for monitoring the fetal heartbeat . In the case of the anterior placenta, that might be difficult since the placenta is between the hearing aid and the fetus.
- Baby’s kicks: You cannot feel the baby’s kicks and movements since the placenta acts as a cushion between your abdomen and the uterus. In the case of an anterior placenta, you could feel muted movements and delayed kicks when compared to those with a posterior placenta.
- Baby’s position: Since the movements cannot be appropriately detected, it might not be easy to determine the baby’s position.
This prevents you from learning about the baby’s development as easily as the other mothers could. And that is annoying!
Does Anterior Placenta Affect Your Baby’s Growth And Development?
The anterior placenta may not affect the baby’s development or health. It may not make any difference to the fetus as long as it is cushioned in the placenta.
Does Anterior Placenta Affect Your Labor and Delivery?
There is a chance of normal delivery even with an anterior placenta, as long as the vaginal opening is not closed. Even in this case, the placenta gets separated from the uterine wall and is removed and sent for analysis, if necessary.
However, research states that the anterior placenta might increase the need for labor inducement and a cesarean section. It might also delay the start of labor. There is also a slightly higher risk of postpartum hemorrhageiXHeavy blood discharge from blood vessels after childbirth (PPH) during vaginal deliveries (6).
What Are The Complications Of Having An Anterior Placenta?
An anterior placenta might not cause any complications during pregnancy. However, it could create complications during labor and delivery, when it grows towards the cervix instead of growing up towards the uterus.
- It might pose risks during a c-section. The placental position could make the incision more difficult, thereby resulting in heavy bleeding during delivery. The anterior placenta may, therefore, increase the risk of excess bleeding during vaginal delivery too (6).
- Needle positioning may become challenging in the case of amniocentesisiXAn amniotic fluid sample test done to diagnose specific genetic abnormalities and birth problems , resulting in bleeding and tears in the membrane.
- Women with an anterior placental position are likely to experience low back pain (7). You may develop back labor, which is a severe pain in the back that occurs with the contractions during labor.
- A low-lying anterior placenta might increase the chance of placenta previa, which might partly or completely block the cervix, increasing the need for a c-section (8).
- Anterior placenta over an old C-section scar might lead to placenta accreta (9), which causes the placenta to grow deep into the scar and also the uterine wall.
- When the baby is in the breechiXIt refers to the fetus in the longitudinal position, with the buttocks and feet facing the pelvis position, your doctor performs a cephaliciX A procedure that involves exerting external pressure on the fetus to move its head toward the pelvis presentation for a smooth vaginal birth. But with an anterior placenta, it might not be possible to turn the baby from a breech position to head-down position, especially if it is low-lying anterior placenta (10).
An ultrasound and MRI scan might help detect the above conditions so that the doctor can plan for a cesarean delivery accordingly.
The anterior placenta is also known to increase the risk of (8).
- Pregnancy-induced hypertension
- Gestational diabetes mellitusiXA condition in which a placental hormone prevents the body from adequately using insulin, leading to increased blood glucose
- Placental abruptioniXWhen the placenta separates from the uterine inner wall before the baby is born
- Intrauterine growth retardationiXPoor growth of the baby in the uterus due to lifestyle practices or specific health conditions
- Intrauterine fetal loss
These risks to the mother and the child could be rare. Regardless, it is best to consult a doctor to stay safe.
When To See A Doctor?
Check for the following signs and symptoms that might indicate placental issue:
- Strong uterine contractions
- Abdominal pain
- Vaginal bleeding
- Severe back pain
If you have suffered an impact to your belly during a fall or trauma, get the injuries checked by a doctor. These injuries might affect placental health and may warrant a medical examination.
Besides the doctor’s recommendations, a few homecare tips could also help to maintain placental health.
Home Care In The Case Of An Anterior Placenta
The following measures will keep up the placental health irrespective of any position. They will also make labor easy, thus keeping both the mother and the baby healthy.
- Eat well for nourishing the placenta. Include more leafy green vegetables, whole grains, nuts, and healthy fats. Minimize the consumption of processed and salty foods.
- Hydrate yourself by drinking more water and juices. Placenta requires fluids to drain the fetal waste.
- If you are allowed to exercise, brisk walking, prenatal yoga, and pelvic floor exercises can be helpful. Take precautions, and do not overdo them (12).
- Avoid sudden jerks to the body – don’t plop on to the sofa or drop yourself into a forward-leaning inversion suddenly. Minimize sudden movements such as forward bends or twists. Wear a seat belt while traveling.
- Avoid smoking and narcotics that may harm your placenta and fetus (13).
Studies About Anterior Placenta
- In a retrospective Turkish study of 500 healthy pregnant women, it was found that the birth weight of fetuses with anterior placenta was higher compared to normal placental pregnancies. Also, the incidence of an anterior placenta was found to be higher in the case of female births.
- Another study conducted in Abha General hospital of Saudi Arabia showed that the majority of women with an O-positive blood group had an anterior placenta (8).
- Sleep position during conception also influences the placental implantation site, found another study carried on singleton pregnancies of gestational weeks between 15 and 20 (14).
The maturation of the placenta, according to the gestational age, is explained through a detailed classification system, which we talk about next.
Placental Grading (Grannum classification)
Placental grading is the classification of the ultrasonographic morphology of the placenta, based on its maturity. It reflects the extent of calcificationiXHardening of a part of the body such as the tissue, blood vessels, or organs due to accumulation of calcium in those parts with the gestational age. The placenta is grouped into four grades, from grade zero to three (11).
- Gestational age: between late first trimester and early second trimester, i.e., less than 18 weeks.
- The chorionic plate is straight, smooth, and a well-defined, unbroken dense line.
- The placental substance is a uniform echotexture with no echogenic areas.
- No basal layer echogenicities
- Gestational age: mid-second trimester to early third trimester, i.e., 18 to 29 weeks.
- It is the early stage of placental maturation.
- The chorionic plate is a well-defined unbroken line which may have fine undulations.
- The placental substance contains a few echogenic areas that are randomly scattered.
- Gestational age: Late third trimester, i.e., beyond 30 weeks.
- The chorionic plate has more marked indentations.
- The placental substance is incompletely divided with linear echogenic densities.
- Larger calcifications are present in the basilar plate with a ‘dot-dash’ configuration.
- Gestational age: Beyond 39 weeks, i.e., when the placenta is mature.
- The chorionic plate has complete indentations.
- The placental substance is divided into compartments that demarcate the cotyledons.
- The basal layer is denser and bigger.
Calcification, as above, is considered normal and healthy. However, there is a chance of premature calcification in case of pre-existing conditions such as placenta previa, high blood pressure, diabetes, or anemiaiXA condition wherein the body lacks sufficient healthy red blood cells for adequate oxygen transport . Calcification will not affect fetal development in any way.
Next, we answer some frequently asked questions about the anterior placenta.
Frequently Asked Questions
1. Can the placenta move from an anterior to the posterior position?
The placenta does not move once it is attached or implanted. So, it cannot shift from an anterior position to a posterior one.
2. Do contractions feel different with an anterior placenta?
Since the anterior placenta is likely to create a cushioning effect between the fetus and the uterine wall, you might not feel the contractions. But the strength of the contractions is the same as when the placental position is normal.
3. Does anterior placenta make your belly look bigger?
The placenta in the anterior position is likely to make your belly look smaller because it is located towards the abdominal wall and squeezes in the excess water and baby parts in between the internal organs..
4. Can a twin hide behind an anterior placenta?
There may not be a chance of a twin hiding behind a placenta. However, it could be possible when the twins are sharing the same placenta and amniotic sac. Here, they are positioned so closely that they may not be detected easily in a scan.
5. How should I sleep when I have an anterior placenta?
Irrespective of the placental position, you should try and get into the habit of sleeping on your side, which is a comfortable position during pregnancy. It is better when you sleep on your left side as it could improve the flow of blood and nutrients to the placenta, fetus, and uterus (15).
6. How common is an anterior placenta?
Although uncommon, the anterior placenta may occur occasionally. Approximately 50% of women may have a placenta before the uterus during pregnancy (16).
7. Does the anterior placenta affect the C-section?
An anterior placenta does not affect the location of a C-section incision, as the procedure will be performed after a thorough evaluation by a healthcare provider (16). However, when complicated by other placental conditions such as placenta previa, anterior placentation may increase the risk of bleeding during c-section (2).
In the anterior placental position, the movements of the placenta are not that easily detectable. Although it is usually not a cause for concern, hearing the baby’s heartbeats or feeling the kicks might not be possible. In the case of the anterior placenta growing towards the cervix and not towards the uterus, the chances of having lower back pain and cesarean delivery are relatively higher. You should check with your doctor immediately if you experience signs of vaginal bleeding or strong uterine contractions that could be possible signs of placental issues.
Infographic: Anterior Placenta: Possible Consequences During Pregnancy And Delivery
An anterior placenta may not cause harm to pregnancy but may increase the risk of certain health conditions. Browse through the infographic to learn about the possible adverse consequences of the anterior placenta during pregnancy and childbirth. You may save and share it with other expecting women.
- The placental position is assessed during the 20th week ultrasound scan, which is also known as the anomaly scan.
- An anterior placenta can make it challenging to hear the baby’s heartbeat, track or feel baby movements, or detect the baby’s position.
- Having an anterior placenta increases the risk of needing labor induction and C-section.
- Some signs of placental issues include strong uterine contractions, abdominal pain, vaginal bleeding, and severe back pain.
- Women with an anterior placenta should avoid narcotics and sudden movements, eat a healthy diet, and stay adequately hydrated.
2. Yosuke Baba et al.; Anterior placentation as a risk factor for massive hemorrhage during cesarean section in patients with placenta previa; The Journal of Obstetrics and Gynaecology Research; Wiley Online Library (2014)
3. 9. Screening for fetal anomalies; Antenatal Care: Routine Care for the Healthy Pregnant Woman; NICE Clinical Guidelines (2008)
4. M. Nagwani et al.; Ultrasonographic Evaluation of Placental Location in Third Trimester of Pregnancy in Relation to Fetal Weight; IOSR-JDMS (2016)
5. You And Your Baby: Month-by-month; Family Birth Place; University of Illinois Hospital & Health Sciences System
6. Torricelli M et al.; Anterior placental location influences onset and progress of labor and postpartum outcome; Placenta (2015)
7. Orvieto R et al.; Low-back pain of pregnancy; Acta Obstet Gynecol Scand (1994)
8. Shumaila Zia; Placental location and pregnancy outcome; J Turk Ger Gynecol Assoc (2013)
9. Placenta Accreta; USF Health Obstetrics and Gynecology
10. Haruyama Y; Placental implantation as the cause of breech presentation; Nihon Sanka Fujinka Gakkai Zasshi (1987)
11. D. Deopa et al.; “Comparison Of Placental Grading By Ultrasonographic Study In Normal And High Risk Pregnancy In North Indian Population”; J Anat Soc India (2011)
12. Keep your placenta healthy by exercising while pregnant; The Physiological Society; ScienceDaily (2019)
13. What is the placenta; NHS (2018)
14. Magann EF; Dominant maternal sleep position influences site of placental implantation; Mil Med (2002)
15. Sleeping Positions During Pregnancy; University of Rochester Medical Center
16. Anterior Placenta; Cleveland Clinic.