The placenta is a temporary organ that develops during pregnancy, acting as a life support system by delivering oxygen and nutrients to the baby while removing waste through the umbilical cord. An “anterior” placement means the placenta has attached to the front wall of the uterus, closest to the mother’s abdomen. This position is determined early on and is a matter of chance, not a reflection of a problem with the pregnancy.
Understanding Placental Placement
The placenta must implant somewhere along the inner surface of the uterus. An anterior placenta is one that has attached to the front wall of the uterus, placing it closest to the mother’s abdomen. Other common locations include posterior (on the back wall near the spine), fundal (at the top of the uterus), and lateral (on the left or right side).
The placement is established in the first few weeks of pregnancy when the fertilized egg embeds itself. The anatomy scan, usually performed between 18 and 21 weeks, is the standard time when the position is confirmed. Although the placenta does not actually move, as the uterus expands throughout pregnancy, a placenta that was initially low may appear to shift upward and away from the cervix.
Is Anterior Placement Safe
An anterior placenta is a common variation and is not considered a complication for the health of the mother or the baby. The placenta performs its function of providing nourishment and oxygen equally well regardless of its location. It is estimated that up to half of all pregnant people have an anterior placenta, making it one of the most frequent locations.
It is important to distinguish an anterior placenta from placenta previa, a condition where the placenta is low-lying and covers all or part of the cervix. While an anterior placenta may be low-lying and require monitoring, the true concern is the proximity to the cervix, not the placement on the front wall itself.
Impact on Fetal Movement Perception
The most noticeable difference with an anterior placenta is the perception of fetal movement. Because the placenta is positioned between the baby and the mother’s abdominal wall, it acts like a cushion. This barrier can significantly dampen the force of the baby’s movements, especially in the early stages.
The first recognizable feeling of movement, often called quickening, may be delayed. While many people feel movement around 18 weeks, those with an anterior placenta may not feel regular kicks until after 20 weeks or closer to 24 weeks, particularly in a first pregnancy. As the pregnancy progresses, movements may feel softer or more subtle directly on the front of the belly. This cushioning effect can also sometimes make it more challenging for a healthcare provider to locate the baby’s heart rate with an external Doppler device.
Considerations During Labor and Delivery
For the vast majority of pregnancies, an anterior placenta does not affect the process of labor or the possibility of a vaginal delivery. The position of the placenta does not impact the intensity or timing of contractions. However, the location may slightly influence planning for a Cesarean section (C-section) if one is required.
In the event of a C-section, the surgical team is aware of the placenta’s anterior location, which is noted on the ultrasound report. Surgeons may use real-time ultrasound guidance to adjust the incision site or technique to avoid cutting through the placental tissue. Furthermore, an anterior placenta has been linked to a slightly higher chance of the baby settling into an occiput posterior position, or “sunny-side up,” which can sometimes contribute to back labor. The placenta is delivered in the third stage of labor, and the anterior position rarely causes issues.