Posts Tagged ‘Rh disease’

What is a maternal-fetal medicine specialist?

Friday, March 15th, 2013

A maternal-fetal medicine specialist is an obstetrician who concentrates on the care of pregnant women and babies in high-risk situations. Another name for this doctor is a perinatologist.

A maternal-fetal medicine specialist treats women with a number of conditions. Complications with mom’s health, include:
• A history of multiple miscarriages or premature birth
• Diabetes (gestational or preexisting)
• Hypertension (high blood pressure)
• Preeclampsia
• Infectious disease (toxoplasmosis, parvovirus, HIV/AIDS, etc.) or chronic illness
• Rh disease
• A family history of heart, kidney, or other disease

A maternal-fetal medicine specialist often treat pregnant women who are carrying multiples (twins, triplets or more) as the risk for preterm birth is significantly increased.

This doctor also specializes in the care of women whose baby is known to have:
• Abnormal fetal growth
• A known birth defect or suspected genetic disorder, such as Down syndrome, Trisomy 13 or Trisomy 18
• A baby with macrosomia (too large)
• A baby with fetal growth restriction (too small)

If you find yourself in a position where the risk of complications is higher than the average pregnancy, ask your current health care provider for a referral to a maternal-fetal medicine specialist. You may or may not need the extra care, but it will be good to get a second opinion.

What is Doppler ultrasound?

Tuesday, October 16th, 2012

Doppler ultrasound is a noninvasive prenatal test that can be used to check a baby’s health in high-risk pregnancies. Providers usually use Doppler ultrasound during the last trimester, but it may be done earlier.

During Doppler ultrasound, your provider or ultrasound technician holds a plastic tool, called a transducer, against your skin to measure the blood flow in the umbilical cord and some of your baby’s blood vessels. (Regular ultrasound will show you a still image, but it cannot show the actual blood flow.) High-frequency sound waves are bounced off circulating red blood cells to project the image of the flow. This test shows if your baby is getting enough oxygen. Your provider also can listen to your baby’s heartbeat using Doppler ultrasound.

Some providers use Doppler ultrasound to check mothers with Rh disease.  This is a condition where a difference between the mother’s blood and baby’s blood can cause a dangerous kind of anemia in the baby. Anemia is when the body doesn’t have enough red blood cells or the red blood cells are too small. When the condition is found early and treated, most affected babies survive. Doppler ultrasound has reduced the need for amniocentesis to monitor fetuses at risk of Rh disease.

Understanding the Rh factor

Thursday, July 7th, 2011

The Rh factor is an inherited protein found on the surface of red blood cells. Most people have this protein and are called Rh-positive. Some people, however, don’t have protein; they’re called Rh-negative.

In the U. S., about 15% of the white population, 5-8% of the African-American and Hispanic populations, and 1-2% of the Asian and Native American populations are Rh-negative. Being Rh-negative doesn’t affect a person’s health in any way.

Problems can arise, however, when an Rh-negative mother and an Rh-positive father conceive an Rh-positive baby. When this occurs, some of the fetus’s Rh-positive red blood cells may get into the mother’s bloodstream during pregnancy, labor and birth. Because red blood cells containing the Rh factor are foreign to the mother’s system, her body tries to fight them off by producing antibodies against them. This is called sensitization.

Once a woman becomes sensitized, her Rh antibodies can cross the placenta and destroy some of the red blood cells of an Rh-positive fetus. In a first pregnancy with an Rh-positive baby, there usually are no serious problems because the baby often is born before the mother is sensitized, or at least before the mother produces many Rh antibodies. However, a sensitized woman continues to produce Rh antibodies throughout her life. This means that in a second or later pregnancy, an Rh-positive baby is at risk for more severe Rh disease. Fortunately, treatment usually can prevent Rh disease.

A simple blood test can tell if a woman is Rh-negative. Every woman should be tested at her first prenatal visit, or before pregnancy, to find out if she is Rh-negative. Another blood test can show if an Rh-negative woman has become sensitized.

An unsensitized Rh-negative pregnant woman can be treated with shots of a purified blood product called Rh immune globulin (RhIg) to prevent sensitization. She most likely receives RhIg at 28 weeks of pregnancy and again within 72 hours of giving birth if a blood test shows that her baby is Rh-positive. She does not need an injection after delivery if her baby is Rh-negative. Some health care providers recommend an additional RhIg injection if a woman’s pregnancy goes past her due date.

An Rh-negative woman should be treated with RhIg after any situation in which the fetal red blood cells can mix with her blood, including: miscarriage, ectopic pregnancy, induced abortion, amniocentesis, chorionic villus sampling (CVS)abdominal trauma, external cephalic version (when the health care provider attempts to turn a breech-position baby into head-down position before labor).

An Rh-negative woman does not need treatment with RhIg if blood tests show that the baby’s father is Rh-negative. If the father is Rh-negative, the baby is Rh-negative. An Rh-negative baby is not at risk of Rh disease.