Types and what diagnosis means
Doctors evaluate whether the placenta covers the internal os and how far its edge is from it. The diagnosis made before 20–24 weeks is most often inconclusive: the lower segment of the uterus is stretched and the placenta moves upward. Therefore, the final decision is made by control ultrasound at approximately 32 weeks, and if low placentation persists, again at 36 weeks. When presenting after a cesarean section, it is important to exclude the placenta from growing into the uterine wall.
- Complete presentation - the placenta completely covers the pharynx
- Regional and partial - partially covers the pharynx
- Low placentation - the edge of the placenta is closer than 2 cm to the pharynx
- Placenta accreta - the placenta penetrates the wall of the uterus, often into the scar
Causes and risk factors
The fertilized egg attaches to the part of the uterus where the mucous membrane is most suitable for this. If the upper sections are changed after surgery or inflammation, attachment may occur lower. The likelihood of presentation increases with each cesarean section and other interventions on the uterus. The lifestyle itself during pregnancy does not affect the location of the placenta, and the diagnosis is not the woman’s fault.
- Previous caesarean section
- Abortion, curettage, fibroid removal
- Placenta previa in a previous pregnancy
- Multiple pregnancy
- Pregnancy after IVF
- Smoking, age over 35 years
Symptoms
Presentation is often detected by chance during a routine ultrasound, when there are no complaints. A typical symptom is sudden, painless bleeding of bright red blood in the second half of pregnancy, often at rest or during sleep. The first bleeding may be small and stop, but repeated bleeding can be stronger. Bleeding can be triggered by sexual intercourse, examination, physical activity, or the onset of contractions. Any bleeding is a reason to immediately seek help.
- Painless scarlet bloody discharge
- Recurrent episodes of bleeding
- Incorrect position of the fetus, high position of the head
- Signs of anemia with repeated blood loss
Diagnostics
The main method is ultrasound. Transvaginal examination during presentation is safe and more accurate than abdominal examination for measuring the distance from the edge of the placenta to the pharynx. Vaginal examination with fingers is not performed with known or suspected presentation, as it may cause bleeding. If there is a scar on the uterus, the doctor evaluates signs of ingrowth using Doppler ultrasound, and sometimes prescribes an MRI. The blood type, Rh factor and hemoglobin level are determined in advance.
- Ultrasound of the fetus in the second trimester
- Transvaginal ultrasound for clarification
- Control ultrasound at 32 and 36 weeks
- Doppler ultrasound or MRI if ingrowth is suspected
- Complete blood count, blood group and Rh
Regimen, treatment and childbirth
With presentation without bleeding, the woman is usually observed on an outpatient basis, but must quickly get to the maternity hospital if discharge appears. It is recommended to exclude sexual activity, heavy lifting and intense exercise. In case of bleeding, they are hospitalized: in case of minor blood loss and prematurity, they try to maintain the pregnancy, administer drugs to mature the fetal lungs, and treat anemia. In case of complete presentation, childbirth is carried out by planned cesarean section, usually at 36–37 weeks; in case of severe bleeding - urgently at any time.
- No sexual contact or heavy exercise
- No vaginal examinations or procedures
- Treatment of anemia before childbirth
- Hospitalization for any bleeding
- Elective caesarean section in complete presentation
- Childbirth in a hospital with a blood supply
