This leaflet is to help you understand what Placental Angioma is, what tests you need and the implication of being diagnosed with Placental Angioma for your baby and your family.
What is a placental chorangioma?
Chorangiomas are benign vascular tumors of the placenta, the temporary fetal organ that attaches to the wall of the uterus (womb) and serves to supply nutrients and oxygen to the fetus during pregnancy. Chorangiomas occur in approximately 0.5% to 1% of pregnancies. While most are small and asymptomatic, having no effect on the course of the pregnancy, larger tumors (greater than 4-5 cm) can lead to complications. The incidence of large chorioangiomas can vary from 1:3500 to 1:9000 (0.29%-0.11%).
How can chorangioma affect my baby or me?
In most cases, chorangiomas are small or microscopic and do not affect the baby. Unfortunately, in cases when chorangioma is bigger than 4 cm or well vascularized, it can have a negative impact on the growing fetus. In those cases, baby may be small for gestational age, or suffer from anemia, heart failure, or hydrops (accumulation of fluid in the body) or die during pregnancy. In such cases, an excess of amniotic fluid is often produced, which may cause distension (overstretching) of the uterus and preterm delivery. For the mother, chorangioma may lead to preeclampsia, with high blood pressure and possible other organs being effected, or mirror syndrome, a condition where hydrops in the baby causes fluid collection in the mother.
What are the things to watch for during my pregnancy?
Regular ultrasounds with Doppler studies are used to monitor tumor size, fetal growth, amniotic fluid volume, and signs of fetal anemia or heart failure. The frequency of exams will be determined by your caregivers, based on tumor size and associated complications. Usually in cases of small tumors this would be every 3-4 weeks, whereas in the case of large tumors the ultrasound scan may be done every 1-2 weeks. Regular ultrasound scans will help to diagnose conditions that require intervention, such as polyhydramnios, hydrops of the baby, or hemolytic anemia. Having information about these conditions will allow your caregiver to plan the care for you and your baby (including delivery) better.
Will it have influence on my baby after delivery?
Chorangioma itself will not affect the future of the baby, because it does not invade or metastasize. However, the complications appearing during pregnancy, especially ifthe delivery is premature and hydrops develops, may impact the baby.
Will it happen again?
The risk of chorangioma happening again is the same as for the rest of the population, or about 1 in 100. It is important to rememberthat even if it does happen again,the course of pregnancy may be totally different, because most chorangiomas are small and do not threaten the baby.
Will I need an invasive procedure during pregnancy?
In some complicated cases with large or symptomatic tumors, in-utero interventions may be necessary. Each case is unique, so the need for intervention is always considered individually. The specialist caring for you will explain which interventions are available and recommended in your individual case. There are invasive procedures that aim to reduce the blood supply to the tumor, or in some cases intrauterine transfusions may be administered to the fetus to treat fetal anemia detected via Doppler studies. Excess amniotic fluid may be removed in cases of polyhydramnios (excess fluid), to reduce uterine tension and the risk of preterm labor
What other questions should I ask?
- What is the size and location of the chorangioma?
- Are there any signs of fetal complications?
- What monitoring schedule should I expect?
- Are any in-utero interventions recommended?
- Where is the best facility for my delivery, considering the chorangioma?
Last updated: March 2025
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