Ultrasound monitoring protocol

Ultrasound monitoring protocol

Tests performed in our Prenatal Diagnosis Unit
Click on the desired test to get more information:

Biochemical – Aneuploidy Ultrasound Screening (EBA Test)

It is a blood test that we perform between the 11th and 14th week aiming at determining certain hormonal values. This information is entered in a software program which, depending on the age of the mother, her weight, number of weeks into pregnancy, the nuchal nape and the CRL (length of the embryo), obtains a risk index of the Down Syndrome or the mongolism (trisomy 21) and the Edward Syndrome (trisomy 18). The obtained information can never be considered as an accurate diagnosis.

The sensitivity to this test is between 85-90%. If we don’t perform the EBA Test, we can ask for the Triple screening from the 15th week up to the 18th week.

11-14th week ultrasound: nuchal nape

During this period, we measure the nuchal nape, the space between the vertebral column and the skin of the fetus at the level of the back. We also evaluate the presence of the nasal bone and the fetal anatomy in the first trimester. If there is an increased nuchal nape, or the nasal bone is missing or there is an important anatomic alteration, we recommend performing an amniocentesis to analyze the fetal genetics (Karyotope).


It is practiced between the 15-18th weeks and a thin needle under ultrasound monitoring is inserted in the amniotic pocket to extract between 15 and 20 cc of amniotic liquid. Amniocentesis is the most reliable test that we have at our disposal (close to 100% reliability) to diagnose genetic alterations.

On the other hand, it has a risk of abortion of approximately 0.5-1%. After the test, we have to rest for close to 48 hours. The final results (fetal Karyotope) are provided at the end of 3 weeks, but we have (for an additional laboratory cost) a quick screening system (QF-PCR), that you can ask for on the day of the insertion.

Amniocentesis is recommended in the following cases:

  • Age of the mother greater than 37 years.
  • Previous child showing Down syndrome (mongolism) or other chromosome alterations or malformation of unknown filiation.
  • Mental slowness in family or congenital physical defects.
  • One of the members of the couple (or both) is a carrier of a chromosome alteration (for instance, chromosome translocation).
  • Recessive, Autosomal diseases or diseases related to the sex, metabolic problems, congenital or hemoglobin problems in the family.
  • Certain chronic diseases in the mother (diabetes of type I).
  • In Vitro Fertilization Cycle due to a severe male factor and/or alterations at the level of the meiosis, FISH, DNA fragmentation, etc.
  • Pre-implant genetic diagnosis (DGP) of the embryo after an In Vitro Fertilization cycle.
  • Suspected risk of fetal infection.
  • Suspected risk, after an ultrasound, that the fetal is a carrier of a chromosome.
  • Triple screening with a risk index higher than normal.
  • EBA test (or OSCAR), with an individual risk index greater than normal.
  • Suspected risk or evidence of a fetal malformation.

High Definition Ultrasound (20 weeks or Morphologic)

It is a high resolution ultrasound which helps remove any structural anomaly, and the chromosome markers in the fetus. We also evaluate the fetal anomaly, the location and characteristics of the placenta and of the umbilical chord, and the volume of amniotic liquid. This ultrasound is performed in our Prenatal Diagnosis Unit by a specialist (level III of SESEGO).

Obstetric Ultrasound 4D (three-dimensional in real time)

It is absolutely normal that the future parents become impatient to know the physiognomy of their child. Various studies have been carried out to suggest that the possibility to do it before the birth of the child reinforces the emotional link.

It’s one of the main functions of the Ultrasound 4D, and it’s carried out in the same way as a traditional ultrasound, but it’s used to obtain images of the fetus in three dimensions (3D ultrasound) and in real time (4D ultrasound).

The zoom-in view of the movements of the future baby helps us observe his behavior in the uterus.

Performed between the 26th and 32nd week of pregnancy, the 4D ultrasound is used to obtain high quality images which appear very true, that we will then hand over to you in a DVD.

The 4D ultrasound, except if otherwise specified by the gynecologist is not used for diagnosis or as support during the pregnancy, and it does not substitute the normal ultrasound tests.

At Procrear, we make sure, during the entire period, to obtain the best 3D and 4D ultrasound images and videos. We commit, in case the position of the baby is not the most appropriate one, to repeat the 4D ultrasound session on another day, without any additional cost.

Doppler ultrasound in color

The Doppler technique has been in use since a long time to analyze the beating of the heart of the fetus. Its application was recently extended in the obstetric domain to measure the wellbeing of the fetus. We can also detect a reduction in the blood flow of the fetus or the placenta, associated to fetal problems (delayed urine increase, etc.).

Echocardiography (study of the heart of the fetus)

Congenital alterations of the heart constitute in the most frequent fetal malformations. Most of these alterations appear in pregnant women without any risk factor. At Procrear, our Prenatal Diagnosis and Neonatal Cardiology and Pediatrics Departments use all their experience to detect these alterations.

Last Update: 09/09/2014
– Asim Kurjak, ‪Frank A. Chervenak. Ecografía en Obstetricia y Ginecología. ‪
‪Ed. Médica Panamericana‬ (2009)
– Wax J, Minkoff H, Johnson A, et al. Consensus report on the detailed fetal anatomic ultrasound examination: indications, components, and qualifications. J Ultrasound Med 2014; 33:189.