In a high-risk pregnancy, you'll get more than the typical 2-3 ultrasounds, potentially having them as often as weekly or bi-weekly, especially in the third trimester, to closely monitor the baby's growth, placental function, and maternal health conditions like diabetes or hypertension. The exact number depends on your specific risk factors (e.g., age, medical history, twins), but expect frequent monitoring with scans to check fetal well-being and address any emerging issues promptly.
High risk pregnancy. If your pregnancy is considered to be higher risk you will be offered additional scans during the third trimester of your pregnancy. These will be performed at 28, 31, 34, 37 and 40-weeks' gestation.
You will have at least two ultrasounds during your early and middle pregnancy, and in the later parts of your high-risk pregnancy, you may have ultrasounds as often as once a week based on your health needs and situation.
More and more obstetricians refer women for two third trimester ultrasounds, mostly at 28 weeks and 36 weeks, because there is increasing evidence that this allows better detection of growth problems and ensures better outcomes for babies.
Specialized ultrasounds
Three-dimensional (3D) or 4-dimensional (4D) ultrasounds can be used to pinpoint a suspected problem, such as fetal development that's not typical. Ultrasound to measure the length of the cervix can help determine if you're at risk for going into labor early.
A high-risk pregnancy is one in which a woman and her fetus face a higher-than-normal chance of experiencing problems. These risks may be due to factors in the pregnancy itself, or they may stem from preexisting maternal medical conditions, such as cancer, diabetes, or lupus.
While definitive conclusions remain elusive, most studies suggest that ultrasound does not significantly affect the health of the mother or the fetus. The procedure is not painful or uncomfortable, leading some expectant mothers to undergo multiple scans to for keepsakes.
Third trimester (weeks 28-32)
In some cases, we might perform an ultrasound in the third trimester to check your baby's position, the location of the placenta, and the amount of amniotic fluid around your baby. This ultrasound is more common in pregnancies considered high-risk.
Ultrasounds in late pregnancy are performed to assess the growth and health of the baby these are also called a biophysical profile or a growth scan. Some doctors will order this routinely at around 32-36 weeks.
The fetal well-being scan, performed between 36 and 40 weeks of pregnancy, is a vital evaluation during the final weeks before delivery. This scan focuses on assessing the baby's health and the readiness of the mother's body for labour.
Age 35 is considered advanced maternal age, but the risks increase as a woman ages. If you are pregnant and over the age of 30, talk with your doctor about your individual health and discuss plans for helping you and your developing baby maintain a healthy pregnancy.
After the 20-week ultrasound, you'll get your results and, based on them, you may or may not have any additional ultrasounds or more monitoring in your third trimester.
A pregnancy is 'high risk' when the likelihood of an adverse outcome for the woman or the baby is greater than that of the 'normal population'. A labour is 'high risk' when adverse outcomes arise in association with labour. by physiological changes that occur in labour.
If a pregnancy is high-risk, you can count on more frequent health care visits. You might need more ultrasounds to track the growth of your fetus. The most high-risk pregnancies will need regular fetal monitoring to check that the fetus is doing well.
Women who have a pre‐pregnancy body mass index greater than 25 kg m–2 are more likely than those with a body mass index in the ideal range (20–24.99 kg m–2) to have problems conceiving a child and are at greater risk of miscarriage and stillbirth.
Here's what you can expect: Increased Frequency of Appointments: Visits may become more frequent as your due date approaches. We may ask you to come in every two weeks or even weekly, depending on the nature of your high-risk pregnancy.
Late in the third trimester, your doctor or midwife will check to see how far your baby's head has dropped into your pelvis. If your baby is not head-down after 36 weeks, you may have a fetal ultrasound to confirm the position. Your care provider may try version to gently turn the baby into a head-down position.
Ultrasound use in the intrapartum domain has become more advanced in the last 2 decades, with uses to determine fetal head station and rotation, assessment of cervical dilatation, and more advanced models for the prediction of the mode of delivery.
At 36 weeks, a baby's body is nearly fully developed, and they are usually ready to survive outside the womb. At week 34, many of the baby's bodily systems are not yet fully mature, especially the lungs. The lungs do not reach full development until around 36 weeks.
After 33 weeks of pregnancy, your baby's brain and nervous system are fully developed.
How big is your baby at 32 weeks pregnant? Your baby is a little over 16 inches (40.6 cm) long and weighs between 4 and 4 ½ pounds (1.8 to 2 kg).
20-week ultrasound (anatomy scan)
During this ultrasound, your pregnancy care provider can see your baby's sex (if your baby is in a good position for viewing their genitals), detect birth disorders like cleft palate or find serious conditions related to your baby's brain, heart, bones or kidneys.
The ultrasound marker is nuchal translucency (NT) thickness. In pregnancies with Down syndrome, PAPP-A tends to be low, and NT and hCG tend to be raised. The values of these markers are used together with your age to estimate the likelihood of having a pregnancy affected with Down syndrome.
Contrary to common misconceptions, the presence of color on an ultrasound is not inherently bad. Instead, it is a valuable tool that aids healthcare professionals in diagnosing and monitoring various conditions.
Some animal studies suggest that prolonged exposure to ultrasound waves can damage neurological, immunological, and hematological systems, as well as the genetic code of the fetus. Although biologic effects have been described in animal models, there is no evidence that these occur in humans.