Ultrasonography

Ultrasonography has become a very important tool in Obstetrics and Gynaecology.
  • In early pregnancy it is essential to accurately confirm and date, to evaluate its viability, to rule out an ectopic pregnancy (a pregnancy outside the uterus) and to confirm and characterise a multiple pregnancy.

  • Later, between weeks 11 and 14, the ultrasound is necessary to exclude some abnormalies and to calculate the risk for aneuploidies, the most frequent being trissomy 21 (T 21) or Down syndrome. At this point, to measure the fetal nuchal translucency (the existing liquid below the skin of the fetus’ neck) and to evaluate the fetal nasal bone will help a certified professional to accurately detect T 21 in a percentage rate that reaches 75% (the detection rate when only the mother’s age above 35 years is taken into account is around 30%).

The combined first trimester screening adds blood tests to the ultrasound; this biochemical tests dosage two hormones produced by the placenta, the free Beta hCG and the PAPP-A. Thus, between weeks 9 and 14 a screening method with a detection rate of 92% can be achieved.
A good screening test, by achieving a good detection rate for low false positive rates (number of babies with a positive screening and no T 21), allow us to safely suggest a lower number of amniocentesis and, consequently, to lower the miscarriages due to this invasive procedure (the risk of abortion after having an amniocentesis is slightly inferior to 1 %).
  • At 21 to 22 weeks another very important ultrasound should be performed to complement the information from the previous scan. It is a morphology ultrasound examination that evaluates systematically the oorganogenesis. It will help exclude around 75 to 80% of the fetal malformations and to evaluate the risks for premature birth and for fetal growth retardation and/or pre-eclampsia (a complication of pregnancy that includes gestational hypertension) by measuring the cervix and by evaluating the uterine artery pulsatility, respectively.

  • The last ultrasound (should there be no problems during the pregnancy) is usually performed at 30 to 32 weeks; it will focus on fetal size, position, organ development and parameters of fetal well-being.

  • Twin pregnancies usually require more exams, specially the monochorionic (with only one placenta).

  • The conventional ultrasound (two dimensions) must be the basis for each and every fetal study. The 3D or 4D ultrasound, helpful in providing more detailed images in some cases of fetal malformations however,  is not necessary in routine evaluations.

  • Ultrasounds are indispensible obstetric tools in the care of pregnant women and they play a very important role in helping us understand intrauterine life, of which we knew nothing 40 years ago. It is, therefore, very important that the healthcare professionals in charge of these three mentioned tests are fully dedicated and motivated to this new and very specific field of Fetal Medicine.

Gynecological Ultrasound
Gynecological ultrasounds play a strategic support role in an appointment with your gynecologist and it is a routine procedure that cannot be separated from this speciality.

This support focuses mainly on:
  • The clarification of gynecological problems that have been detected in women by their general practitioners (symptoms or abnormal exams/tests);

  • Family Planning, namely in the choice of the more adequate birth control method;

  • The co-operation with the infertile couple, detecting the woman’s problems and being also very important in the performance of medically assisted reproduction procedures;

  • The surgical guidance of the patient and early detection of gynecologic cancer, namely endometrial and ovarian;

  • The choice of the more adequate hormone replacement therapy and monitoring of the endometrium;

  • Is also becoming increasingly important in the evaluation of the woman with urinary incontinence.


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