American hospitals require the following laboratories and ultrasounds as part of the prenatal care.

We recommend to our patients from abroad that they bring the results of these labs from their country of origin in order to not incur in additional laboratory expenses. Laboratories in the third trimester (weeks 30 to 32) are usually performed in our office as patients are advised to be in the United States no later than 34 weeks gestation.



» Initial Laboratories


Rh and Blood Group

Blood Screening for Antibodies

Rubella antibody

Syphilis (VDRL)

Urinalysis and culture

Antibodies for Hepatitis B (HBsAg)

HIV Testing

Hemoglobin electrophoresis

Vaginal cultures for Chlamydia and Gonorrhea


» Laboratories for Weeks 8-18


MSAFP / Multiple Markers IS

The standard for women under 35 years is to make the screening test for Down syndrome and Trisomy. This is done with the integrated test and includes fetal ultrasound for nuchal translucency and multiple markers at 11-13 weeks and the second group of tracers to 16-20 weeks. Alternatively you could choose CVS (chorionic villus sample) or amniocentesis, the latter being the initial recommendation for women whose age at birth is 35 or more.


An 18-20 week the fetal anatomy or second level ultrasound is recommended.


» Laboratories for Weeks 24-28


Screening for Gestational Diabetes

Please do this test from week 26-28. Due to some discrepancies with laboratories abroad, please ensure that the review is done with a glucose load of 50 grams (no fasting is required), 1 hour to measure glucose levels in blood. If the results are abnormal please do a curve of glucose tolerance with a 3-hour load of 100 gm. During the same glucose test repeat the AIDS, Syphilis, Hepatitis and blood tests. As you can see these tests are the same as those made in the 1st trimester (hospitals in the United States require to repeat them in the 3rd trimester).



» Laboratories for Weeks 32-36


Vaginal culture (Chlamydia and Gonorrhea) usually also repeated in the last trimester.

Recto-vaginal culture for group B streptococcus:

This test we usually do in our office at 36 weeks of gestation.