What scans can you expect when you are pregnant with twins?

When pregnant with twins, there are typically more scans and check-ups than with a single pregnancy – this is to ensure that both mother and foetuses are healthy. Twin pregnancies require extra monitoring due to the increased risk of complications. Here is an overview of the most important scans you can expect:

 

1. Early scan – e.g. for fertility treatment etc. (weeks 6-8)

  • Purpose: To confirm the pregnancy and determine if it is a twin pregnancy. It will also assess whether there are one or two placentas, which is important for planning the rest of the pregnancy.

 

2. Nuchal fold scan and 1st trimester scan (weeks 11-13)

  • This scan will usually be your first scan and is where you find out you are expecting twins or triplets.
  • Purpose: To confirm the pregnancy and determine if it is a twin pregnancy. It will also assess whether there are one or two placentas, which is important for planning the rest of the pregnancy.
    Measure the thickness of the foetal nuchal fold to assess the risk of chromosomal abnormalities such as Down’s syndrome. The scan is also used to determine the due date and check the development and growth of the foetus.

 

3. 2nd trimester scan (weeks 18-21)

  • Purpose: This scan, also known as the malformation scan, is used to examine the foetuses’ organs and assess whether they are developing normally. You can also confirm the gender of the twins here if you wish.

 

4. Growth scans (every 2-4 weeks from around week 20)

  • Purpose: Twins are monitored more frequently and closely to ensure that both foetuses are growing as expected and that there are no complications such as growth retardation or transfusion transfer syndrome (TTTS), which can occur with twins sharing a placenta. The frequency of these scans depends on whether or not the twins share a placenta:
    • Separate placenta: Growth scans every 4 weeks.
    • One placenta shared by the children: Growth scans every 2 weeks, especially from week 16-18 to monitor the risk of TTTS.

 

5. Third trimester scans (weeks 28-36)

  • Purpose: Continued monitoring of fetal growth and position. The position of the foetus is also assessed to plan the delivery method, whether vaginal or caesarean section.

 

6. Pre-birth assessment (weeks 36-38)

  • Purpose: A final assessment of the size and position of the foetus and the mother’s condition. Based on this assessment, decisions are made about the birth, including whether a planned caesarean section is needed.

 

Additional checks and scans

  • Additional scans: If complications arise or if doctors are concerned about fetal growth or well-being, more frequent scans and checks may be needed.
    Cervical assessment: In some cases, cervical length is monitored, especially if there is a risk of premature labour.
    Midwife: Some hospitals offer more frequent midwife visits, while others follow the standard for singleton pregnancies.
    Gestational diabetes: You will be called in for a test for gestational diabetes, as a multiple pregnancy carries a higher risk of developing it. If you have gestational diabetes, you will be assigned a dietitian who will help you measure your blood sugar and look at your diet.

 

In conclusion
Twin pregnancies require close monitoring and the number of scans may vary depending on the course of the pregnancy and any complications. It’s important to have a close dialogue with your doctor or midwife to ensure that both you and your twins receive the best possible care throughout your pregnancy.

 

Always remember to contact your doctor or your maternity ward if you experience anything that worries you.

 

Please note that both the number and type of scans may vary depending on the hospital and the type of twins you are expecting. Therefore, this should not be used as a checklist, but as a guide.