Placenta previa

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Classification according to ICD-10
O44 Placenta previa
ICD-10 online (WHO version 2019)

As a placenta previa (Latin for forward-lying placenta , lying in the path of the placenta , by praevius "located in front of the way") is an in the lower uterine segment to lie has come placenta called or the incorrect position of the placenta. The placenta is embedded near the cervix and covers the cervical opening (cervical opening) and thus the birth canal in whole or in part. A placenta previa is only spoken of after the end of the 24th week of pregnancy, as it is still possible that the placenta may change, releasing the birth canal. A caesarean section is often indicated to avoid life-threatening bleeding during labor.

frequency

In around 0.5% of all pregnancies, with multiparous or prolific women being affected much more frequently than first-time women, especially after pregnancies in rapid succession.

causes

The causes are not clearly understood. A frequent occurrence is found after previous caesarean sections , miscarriages , manual placenta detachment (the placenta did not come off after birth and had to be surgically removed), scrapes and several previous births.

Classification

The classification is based on the relationship between the placenta and the internal cervix, whereby the increasing opening of the cervix can lead to a changed placenta-previa shape. A distinction is made between:

  • deep seat of the placenta : part of the placenta is located in the lower part of the uterus (lower uterine segment). Vaginal birth is possible
  • Placenta previa marginalis : the placenta tissue reaches the inner cervix, a vaginal delivery may be possible, but depending on the maternal and child condition
  • Placenta previa partialis : the cervix is ​​partially covered by placental tissue, vaginal birth is not desirable
  • Placenta previa totalis : the placenta lies centrally over the inner cervix, vaginal delivery is not possible. Even with little labor, life-threatening bleeding can occur.

Symptoms

The main symptom of placenta previa is the announcing (warning) vaginal bleeding, usually in the middle of pregnancy. In contrast to the bleeding with premature placental detachment, this bleeding is painless, fresh, bright red and recurring. The pregnant woman does not go into labor, the stomach is soft and not sensitive to pressure. The placenta previa can also be accompanied by the following irregularities: the child's head has not yet established a relationship to the mother's pelvis in primiparous women near the appointment, or has incorrect position or pole position ( breech position , transverse position ).

diagnosis

The diagnosis should be made on the basis of the clinical symptoms, a detailed ultrasound examination to determine the exact placental location, possibly speculum adjustment , but under no circumstances by a vaginal examination, as this can lead to life-threatening bleeding.

therapy

When diagnosing placenta previa, the further procedure depends on the bleeding intensity, the condition of the mother and child, the gestational age and the type of placenta previa. Clarification (also for the differential diagnosis of premature placental detachment) is necessary, possibly an inpatient admission.

In the case of heavy bleeding, multiple large-lumen accesses and aggressive volume therapy are used for shock therapy . An emergency caesarean section after transport to the hospital is then necessary.

source

  • Mändle, Opitz-Kreuter, Wehling "The midwife book textbook of practical obstetrics", Schattauer-Verlag, ISBN 3-7945-1765-2 .