Posts Tagged ‘blood’

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.

Saving my baby’s umbilical cord blood: Should I do it?

Thursday, August 27th, 2009

As soon as you get pregnant, you may find yourself drowning in ads encouraging you to save the blood from your baby’s umbilical cord. What’s a mother to do?

The hope is that this blood might be able to protect the baby from some serious diseases in the future. But many scientists have doubts and concerns.

This is a complicated subject. Storage can be expensive, and its benefits are not clear. The March of Dimes fact sheet lays out the pro’s and con’s.

The American Academy of Pediatrics (AAP) has a position on the issue. For families who do not have a history of certain diseases, the AAP thinks it is unwise to store cord blood in a private blood bank. The AAP and many scientists favor the collection and storage of cord blood in public banks.

WNYC, a radio station in New York city, ran a good feature this week on this topic. Give a listen.

Have you made your decision? Please tell us about it.

Infections after c-section

Thursday, August 13th, 2009

mom-with-newborn1Did you know? Women who have a c-section are more likely to develop a postpartum infection than women who have a vaginal delivery.

A new study from Denmark looked at the records of over 30,000 women who had given birth. Those who had a c-section were at increased risk of having a urinary tract infection (UTI) or a wound infection within the first 30 days after delivery. (A wound infection affects the area where the incision was made.) Other studies have also found an increased risk of infection after cesarean.

So if you have a c-section, be on the alert for these signs:

* For a UTI, watch for pain or burning when you go to the bathroom, blood in your urine, fever and the urge to go often.

* For  wound infection, watch for redness, swelling or pus around the incision site. Sometimes, the wound may open, and you may run a fever.

For more information, read the March of Dimes article on cesarean birth. Or watch our video C-Section: Recovering After Surgery.