Ultrasound scans are often one of the most eagerly anticipated moments for expectant parents. The excitement is present from the first scan to the last, making each appointment a deeply emotional experience.
Throughout pregnancy, a series of ultrasound scans is recommended to check that the baby is developing properly and that the pregnancy is progressing as expected. They also give parents the opportunity to see how their baby is growing.
But how many ultrasound scans should be carried out during pregnancy? The answer depends on each pregnancy. However, at Clínica Fertia, we have prepared a general ultrasound schedule explaining which scans are usually recommended during pregnancy and what can be observed and assessed at each stage.
Ultrasound Schedule During Pregnancy
Their First Heartbeat
6–10 weeks
An early ultrasound scan, usually performed between weeks 6 and 10 and generally using a transvaginal approach, can help to:
- Confirm that the pregnancy is located inside the uterus.
- Accurately calculate gestational age and the estimated due date.
- Check the number of embryos and identify multiple pregnancies.
- Assess embryonic cardiac activity and confirm that the pregnancy is progressing.
Their Little Hands
10–14 weeks
This is known as the first-trimester ultrasound or ultrasound marker scan. It is usually performed abdominally and can assess:
- Appropriate fetal growth and whether it corresponds with gestational age.
- Ultrasound markers that may suggest a possible chromosomal condition or indicate a higher risk of certain congenital abnormalities appearing later.
- Several ultrasound markers, including nuchal translucency, the nasal bone, ductus venosus and tricuspid valve.
- Early aspects of fetal anatomy, including the limbs, skull, stomach, bladder and abdomen.
This ultrasound should be accompanied by a blood test known as biochemical screening. It measures pregnancy-related hormones associated with certain fetal conditions, including PAPP-A and free beta-hCG.
These blood test results are combined with the ultrasound findings and maternal information, such as age and weight, to produce the combined first-trimester screening. This estimates the risk of the most common trisomies, including Down syndrome.
Their First Kicks
16–18 weeks
At this stage, the scan can assess whether fetal growth is progressing appropriately and evaluate the placenta.
It can also:
- Examine important aspects of fetal anatomy.
- Rule out certain severe abnormalities, particularly those affecting the skull and spine.
- Help determine the baby’s sex.
- Include an early fetal echocardiogram when indicated, for example in cases involving family history or abnormal first-trimester markers.
Their First Expressions
20–22 weeks
This is probably the most important ultrasound scan of the entire pregnancy and is also known as the anomaly scan or morphology scan.
It is carried out at a stage when most fetal organs have developed sufficiently to allow a detailed anatomical assessment. It can detect many structural abnormalities, including approximately 60% of those that can be identified by ultrasound. Chromosomal ultrasound markers are also reviewed again.
It is important to understand that ultrasound cannot diagnose conditions that do not have visible physical signs, such as deafness, blindness, intellectual disability, certain metabolic disorders or inherited diseases.
Some abnormalities are not yet visible at this stage and must be assessed again during the third trimester, including certain kidney and bone abnormalities.
During the morphology scan, the specialist may also assess the uterine artery Doppler and measure the cervix.
Measuring blood flow through the uterine arteries helps to assess how the placenta is functioning and can be used to estimate the risk of pregnancy complications such as pre-eclampsia or fetal growth restriction.
They Begin to Hear Us
24–29 weeks
The purpose of this ultrasound scan is to:
- Confirm that fetal growth is appropriate.
- Rule out fetal abnormalities that may appear later, including skeletal abnormalities, kidney abnormalities and certain congenital heart conditions.
- Assess the appearance and position of the placenta.
- Evaluate the amount of amniotic fluid.
- Examine the fetal umbilical arteries to determine whether blood flow to the baby is adequate.
- Assess blood flow in the fetal cerebral arteries.
The Final Wait
33–36 weeks
The purpose of this ultrasound scan is to:
- Confirm that fetal growth is appropriate.
- Assess the appearance and position of the placenta.
- Check the baby’s presentation, for example whether the baby is head-down or breech.
- Evaluate the amount of amniotic fluid.
- Examine the fetal umbilical arteries to determine whether blood flow to the baby is adequate.
- Assess blood flow in the fetal cerebral arteries.
At Clínica Fertia, we support you throughout your entire pregnancy. Our clinic is equipped with advanced prenatal diagnostic technology so that all the necessary checks can be carried out during pregnancy.
We take care of you and your baby.
Frequently Asked Questions About Ultrasound Scans During Pregnancy
How many ultrasound scans are needed in a normal pregnancy?
In an uncomplicated pregnancy, between three and five ultrasound scans are usually recommended, although additional scans may be required depending on the individual case and medical follow-up.
Are ultrasound scans safe during pregnancy?
Yes. Ultrasound scans are safe, non-invasive examinations that use sound waves to visualise the baby without exposing the mother or fetus to radiation.
Can I have more ultrasound scans than those normally recommended?
Yes. In high-risk pregnancies or when specific monitoring is needed, the specialist may recommend additional ultrasound scans to provide closer follow-up.
Which is the most important ultrasound scan during pregnancy?
The 20-week morphology scan is one of the most important because it allows the baby’s anatomy to be assessed in detail and may detect certain structural abnormalities.
At what week can pregnancy be confirmed by ultrasound?
Pregnancy can usually be confirmed by ultrasound between weeks 6 and 7, when the gestational sac and embryonic heartbeat may already be visible.
Where can I have pregnancy ultrasound scans in Málaga?
At Clínica Fertia, you can receive comprehensive pregnancy monitoring with advanced ultrasound scans and a specialist prenatal diagnosis team in Málaga.
