Fetal invasive procedures are medical interventions performed during pregnancy to diagnose or treat conditions affecting the fetus. These procedures are typically considered when non-invasive methods are insufficient, and they involve direct access to the fetus or amniotic environment. Here’s an overview of common fetal invasive procedures:
1. Amniocentesis
- Description: Amniocentesis involves the extraction of a small amount of amniotic fluid from the amniotic sac surrounding the fetus. The procedure is usually performed between 15 and 20 weeks of pregnancy.
- Uses: It’s used to diagnose genetic disorders, such as Down syndrome, spina bifida, and other chromosomal abnormalities. It can also detect infections and assess lung maturity in the third trimester.
- Risks: There is a small risk of miscarriage (about 0.1% to 0.3%), infection, or injury to the fetus.

2. Chorionic Villus Sampling (CVS)
- Description: CVS involves taking a small sample of the placenta, which contains the same genetic material as the fetus. This is typically done between 10 and 13 weeks of pregnancy.
- Uses: It’s primarily used to detect chromosomal abnormalities and genetic disorders early in pregnancy.
- Risks: Similar to amniocentesis, CVS carries a small risk of miscarriage, as well as potential complications like infection or Rh sensitization.
3. Fetal Blood Sampling (Cordocentesis or PUBS)
- Description: This procedure involves taking a small sample of the fetus’s blood from the umbilical cord. It’s typically performed after 18 weeks of pregnancy.
- Uses: Fetal blood sampling is used to diagnose conditions like fetal anemia, infections, or blood disorders. It can also be used to deliver medications or blood transfusions directly to the fetus.
- Risks: This procedure has a higher risk of complications, including miscarriage, preterm labor, or infection.
4. Fetal Surgery
- Description: Fetal surgery is performed to correct certain birth defects or other issues while the baby is still in the womb. This can involve open surgery, minimally invasive surgery, or procedures like laser therapy.
- Examples:
- Spina Bifida Repair: Surgery to repair spinal defects can be done in utero to improve outcomes after birth.
- Twin-to-Twin Transfusion Syndrome (TTTS): Laser surgery may be performed to correct abnormal blood vessel connections between twins sharing a placenta.
- Risks: Fetal surgery carries significant risks, including preterm labor, infection, and the potential for complications during delivery.
5. Fetoscopy
- Description: A fetoscope, a small camera, is inserted into the womb to visualize the fetus and perform certain interventions. It’s often used in conjunction with other procedures, such as fetal surgery.
- Uses: Fetoscopy is used for diagnostic purposes and to guide surgical procedures, such as treating TTTS or removing a fetal tumor.
- Risks: Similar to other invasive procedures, there’s a risk of miscarriage, preterm labor, and infection.
Summary
Fetal invasive procedures are critical for diagnosing and treating conditions that could impact the fetus’s health or survival. While these procedures carry certain risks, they offer the potential for early intervention, which can significantly improve outcomes for the baby. The decision to proceed with such procedures is usually made after careful consideration of the benefits versus the risks, in consultation with a specialist in maternal-fetal medicine.

Request an Appointment
Need assistance or want to schedule an appointment? Simply fill out the form, and our team will get back to you shortly to confirm your appointment or provide a callback