WEEKS PRENATAL DIAGNOSTIC TESTING

Prenatal Diagnostic Testing Schedule

WEEKS  PRENATAL  DIAGNOSTIC TESTING

Prenatal visits  

• Weeks 0-28: Every 4 weeks. 
• Weeks 29-35: Every 2 weeks. 
• Weeks 36-birth: Every week. 

Initial visit :

Heme:  CBC, Rh factor ,  type  and  screen.

Infectious disease:

UA and culture,  rubella  antibody titer , HBsAg,
RPR/VDRL, cervical gonorrhea and chlamydia, PPD, HIV,  Pap
smear (to check for dysplasia). Consider HCV and varicella based
on history.

If indicated: HbA, sickle cell screening.
Discuss genetic screening:  Tay-Sachs disease, cystic fibrosis.

9- 14  weeks :

Offer PAPP-A +  nuchal transparency + free  B-hCG +/- chorionic
villus sampling  (CVS)

15-22 weeks :

Offer maternal  serum a-fetoprotein  (MSAFP)  or quad screen  (AFP,
estriol,  P-hCG, and inhibin A)  +/- amniocentesis.

18-20 weeks :

Ultrasound for full  anatomic screen.

24-28 weeks : 

One-hour glucose  challenge test for gestational diabetes screen.

28-30 weeks :

RhoGAM for  Rh-8 women (after antibody screen).

35-40 weeks :

Group  B  strep  culture  (GBS);  repeat CBC.

34-40 weeks :

Cervical chlamydia  and  gonorrhea cultu res,  HIV,  RPR  in high-risk patients.