Testing 1-2-3

The prenatal tests you may receive and what they mean

Test
Blood type and Rh factor

Who needs it, when is it performed?
All pregnant women; at first visit.

What's Involved?
A blood sample is drawn and examined.

What does it reveal?
Mother’s blood type and whether she is Rh-negative.

Potential harm to fetus?
None.

What's next? Follow-up:
If Rh-negative, Rh immune globulin is given at 28 weeks.

Test
Pap smear/ gonorrhea culture 

Who needs it, when is it performed?
Women who have not had a recent Pap smear or who are at risk for having gonorrhea; at first visit. 

What's Involved?
Cervical/vaginal secretions are examined.

What does it reveal?
Preexisting medical conditions such as cervical cancer and vaginal infections.

Potential harm to fetus?
None.

What's next? Follow-up:
Depends on findings.

Test
Hematocrit/ hemoglobin

Who needs it, when is it performed?
All; early in pregnancy and at 32–36 weeks.

What's Involved?
A blood sample is drawn and examined.

What does it reveal?
Can indicate anemia.

Potential harm to fetus?
None.

What's next? Follow-up:
If anemic, extra iron will be prescribed

Test
Cystic fibrosis screening 

Who needs it, when is it performed?
Women of certain races and ethnicities who are at risk for carrying the disease; early in pregnancy.

What's Involved?
A blood (or, occasionally, saliva) sample is drawn and examined.

What does it reveal?
Whether mother is a carrier.

Potential harm to fetus?
None.

What's next? Follow-up:
If mother is a carrier, the father may be tested; both may be referred for genetic counseling.