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Pregnancy ultrasound


The routine obstetrical ultrasound screening involves three exams throughout the course of  pregnancy.





First trimester (10th - 14th week)

Screening in the first trimester of pregnancy aims mainly in fetal viability. The number of fetuses, location and fetal heart rate of each fetus is documented. Specific congenital anomalies such as anencephaly or anomalies of the heart and spine may be detected during this time.

Evaluation of the nuchal translucency form the 12th to the 14th week of gestation, in  combination with specific biomarkers provides an early estimation of chromosomal anomalies and may direct to  more invasive screening such as  chorionic villus sampling  (CVS) or amniocentesis.

picture 1


picture 1

Midsagittal                                                            Nucheal Translucency



Anencephaly  Hydrocephalus Omphalocele Gastroschisis Hydronephrosis




Second Trimester (20th - 24th week)

Second trimester screening involves a detailed examination of all vital organs of the fetus such as spine, heart , limbs and brain. The location and the anatomy of the  placenta are  also examined. During this period all the major fetal systems have been organized  the most organs have been completely  formed. Therefore this is the most appropriate time to evaluate the fetus for severe structural anomalies. Unfortunately despite resent improvements in ultrasound technology, the detection rate is only up to 60% .


   Doppler Μητριαίων Αγγείων picture 2




Third Trimester (30th - 34th week)

In the third trimester, sonographic evaluation is focused on embryonic growth, amniotic fluid volume and placental position and maturity.

From  the 32nd to 34th week of gestation a Doppler ultrasound (picture2 and  3) evaluates  the  blood flow from placenta to the embryo and provides additional information on fetal well being.

The  Biophysical  profile is performed between 32th and 40th week of pregnancy and it is co-evaluated with  the Non Stress  Test (NST).This examination is used to monitor fetal well being mainly in high risk pregnancies such as those with gestational diabetes , preeclampsia, intrauterine growth restriction  etc.


Doppler Ομφαλικής Αρτηρίας  picture 3




Invasive fetal monitoring procedures

These procedures are performed to rule out chromosomal abnormalities when there are abnormal results in any of the previous examinations, or to exclude certain congenital infections.

Amniocentesis (16th - 20th week of pregnancy) is performed by inserting a small needle into the amniotic sac and aspirating a small amount of fluid which contains fetal and amniotic cells. These cells are cultured in the laboratory and they are evaluated for chromosomal or other genetic abnormalities as well as for possible infection.

Chorionic villus sampling (11th - 13th week of pregnancy) is performed by aspirating a small amount of tissue from the placenta (chorionic villi).  These cells are also cultured and evaluated in a similar fashion

Overall these procedures are safe bur there is a small risk of trauma, infection or bleeding during or after the procedure, which can eventually lead to the loss of pregnancy in about 1% of the cases.