Prenatal Profile – Blood Bank Testing

Hemolytic disease of the fetus and newborn (HDFN) and other immune-mediated conditions can affect pregnant women, their fetuses, and newborns. The blood bank and transfusion service play critical roles in supporting the diagnosis and treatment of these conditions. The blood bank  performs the testing associated to determine a patient’s eligibility of receiving Rh Immune Globulin and assigning the appropriate dose to a patient. The blood bank provides Rh Immune Globulin to all inpatients. Outpatient provider offices are responsible for providing Rh Immune Globulin to outpatients. A blood type and antibody screen are performed in the prenatal period to identify women at risk of having a pregnancy affected by HDFN (Hemolytic Disease of the Fetus and Newborn) and to establish a history on file at the hospital to facilitate blood product compatibility in the event a transfusion is necessary.

Useful For

Determination of ABO blood group, Rh type, and antibody status for prenatal patients that may require transfusions, Rh Immune Globulin, or antibody titers if clinically significant antibodies are found.

Recommended prenatal profile for Blood Bank testing consists of a Type and Screen (ABO/Rh and antibody screen).

A prenatal patient that is Rh negative may be a candidate for Rh Immune Globulin (Rhogam) to prevent Anti-D alloimunization.

A prenatal patient whose antibody screen is positive, may indicate that the patient has clinically significant antibodies that could put the patient and fetus at risk of Hemolytic Disease of the Fetus and Newborn (HDFN). If the patient has clinically significant antibodies, the prenatal patient’s antibody titers should be monitored throughout the pregnancy.

Method Name

Hemagglutination (Tube and Gel Methods)

Important Note

A patient who is receiving a transfusion or inpatient prenatal patients must have a new Type and Screen specimen drawn and tested every 72 hours as they may develop clinically significant antibodies within that timeframe. All inpatients, or patients potentially receiving a transfusion, must have a Blood Bank Armband applied to their wrist and the Blood Bank Armband Number (BBID) number written on the tube. See special instructions section for more details.

Aliases

Prenatal Profile; Obstetric Profile; Prenatal Type And Screen, Prenatal Type, Prenatal ABO, Prenatal ABO RH, Prenatal Antibody Titers, Antibody Titers, Titers, Rhogam, Rh Immune Globulin,

Specimen Type

Whole Blood

Specimen Required

Dependent on testing needed. 

Type and Screen: Large lavender-top (EDTA) tube, approximately 7 mL

Antibody Titer: Two (2) Large lavender-top (EDTA) tube, approximately 7 mL (This test is a send out to the reference lab)

After the patient is positively identified, the sample is drawn and fully labeled with the following information either electronically or handwritten:

  • Patient’s full First and Last Name
  • Date of Birth or Medical Record Number (MRN#)
  • Date and Time specimen was drawn
  • Blood Bank Armband Number (BBID) (see below for more information)
  • Identify of the person who collected the specimen (Ex: Cerner ID or personnel initials)

Most prenatal outpatient samples do not need a BBID. All inpatients, or patients potentially receiving a transfusion, must have a blood bank armband (BBID) applied to their wrist and the Blood Bank ID (BBID) number written on the tube. This blood bank armband is a secondary patient identifier that helps ensure a safe and accurate transfusion. Specimens received without a blood bank armband will be rejected. See special instructions for more information.

Specimen Minimum Volume

Dependent on testing needed. 

Type and Screen: 1.0 – 4.0 ml

Antibody Titer: One (1) tube 1.0-4.0 ml

Specimen Stability Information

Stable at room temperature for 24 hours.

Rejected Due To

  • If the patient’s full first and last name and date of birth are not clear, accurate, and/or readable the specimen must be rejected.
  • If the Blood Bank Armband Number (BBID) from the Blood Bank Armband is missing, inaccurate, illegible and/or can not be confirmed on all inpatient and outpatient potential transfusion specimens, the specimen must be rejected and sample redrawn.
  • Specimens may be rejected for insufficient quantity and/or quality reasons (Ex: Hemolysis, dilution, etc).
  • If there is any doubt as to the identity of the sample, a new sample must be obtained.
  • If a specimen is rejected on a trauma, OR, or other critical patient when blood is needed urgently/immediately, have the specimen redrawn in accordance with this policy and follow the policy “Issue of Blood in Urgent Situations”. Uncrossmatched blood can still be given in an emergent situation.

Special Instructions

Prenatal Testing for Blood Bank Includes: ABO/Rh type, Antibody Screen, Antibody Titer (if indicated), Rh Immune Globulin (if indicated)

Note: Rh Immune Globulin is not provided to outpatient services by the hospital. Rh Immune Globulin is provided to inpatients who meet the criteria.

The person drawing the blood sample must confirm the patient’s identity by checking at least two independent identifiers before collected a specimen such as: first name, last name, date of birth, and medical record number. If possible, patient identification should be obtained verbally directly from the patient. The phlebotomist must not rely on a bed tag or on charts or records placed nearby. After positively identifying the patient, the sample is drawn and fully labeled with the following information either electronically or handwritten: Patient’s full first and last name, date of birth or medical record number (MRN#), date and time specimen was drawn, Blood Bank Armband Number (see below for more information), and identify of the person who collected the specimen (Ex: Cerner ID or personnel initials).

All inpatients, or patients potentially receiving a transfusion, must have a Blood Bank Armband applied to their wrist and the Blood Bank Armband Number (BBID) number written on the tube. Please write the number clearly and do not use a gel pen (anything written in gel pen smears as the specimen is transported in a bag to the lab). This blood bank armband is a secondary patient identifier that helps ensure a safe and accurate transfusion. Specimens received without a blood bank armband ID will be rejected.

An ABO/Rh retype is drawn on patient’s that do not have a historical blood type on file in the LIS system to confirm their blood type before the patient is transfused. The ABO/Rh retype is to be drawn at a different time and by a different phlebotomist in order to confirm the patient’s blood type to prevent a mistransfusion.

Performing Laboratory

STAT turn around time approximately 30 minutes.
Routine inpatient samples around time is approximately 1- 4 hours.
Routine outpatient samples to 1-2 days.

Reference Values

ABO/Rh Blood Types: O pos, O neg, A pos, A neg, B pos, B neg, AB pos, AB neg

Antibody Screen: Negative (No clinically significant antibodies present) or Positive (Potentially clinically significant antibodies present)

Antibody Titer (if indicated): See reference lab report

Prenatal Rh immune globulin candidates are:

  • Routine prophylaxis administration to Rh negative women at about 28 weeks gestation. (Not provided by hospital. Please see outpatient provider)
  • Rh negative women after abortion or ectopic pregnancy.
  • RhIG is indicated after any event that increases the risk of Feto-maternal Hemorrhage (FMH).

Day(s) and Time(s) Performed

24 hours 7 days a week

Antibody Titers (if indicated) are sent out to the reference lab.

  • Routine 1-2 day turnaround time.
  • Stat about 1 day turnaround time.
    • NOTE: Dependent on when the sample gets to the lab and can be sent to the reference lab in West Henrietta, NY.

Specimen Retention Time

Type and Screen specimens are held for 10 days.

Reflex Tests

  • ABO/Rh retype when a historical blood type is not on file in the LIS system on a patient. Required before a patient is transfused with ABO type specific blood.
  • When a patient’s antibody screen is positive, potentially clinically significant antibodies may be present. An Antibody Identification test (AB ID) will reflex to investigate and determine what is causing the patient’s positive antibody screen.
    • If an antibody identification test can not be completed at the hospital, for example due to a complicated work up and limited resources, the sample may be sent to a reference lab for further workup to determine what is causing the patient’s positive antibody screen. This is essential to determine whether or not there are clinically significant antibodies.
  • Antibody Identification test (AB ID) will reflex to an antibody titer send out if the patient has a clinically significant antibody(ies) that have the potential to cause HDFN.