Richmond Practice - Fetal anomaly scan

Fetal anomaly scan
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During pregnancy, when can you see if my baby is growing normally?

An anomaly scan shows whether your baby is developing normally and where the placenta is lying in your uterus. It is sometimes called your mid-pregnancy ultrasound scan and must take place when you are between 18 and 23 weeks pregnant. It is one of the most important pregnancy scans and helps us find out whether the baby has a disability or not. Unfortunately however the anomaly scan is not 100% accurate and couples need to consent that they understand this.

What we look for particularly:
  • The shape and structure of your baby's head and brain.
  • Your baby's face to check for a cleft lip.
  • Your baby's spine, both along its length and in cross section, to make sure that all the bones align and that the skin covers the spine at the back.
  • Your baby's abdominal wall, to make sure it covers all the internal organs at the front.
  • Your baby's heart and lungs. The top two chambers (atria) and the bottom two chambers (ventricles) should be equal in size. The valves should open and close with each heartbeat.
  • Your baby's stomach and bowels. Your baby swallows some of the amniotic fluid that he lies in, which is seen in his stomach as a black bubble.
  • That your baby has two kidneys, and that urine flows freely into his bladder.
  • Your baby's sex, arms, legs, hands and feet.
As well as this detailed look at how your baby is growing, we check the position of the placenta, the umbilical cord and that there's enough amniotic fluid. During the scan we will measure your baby's head and abdominal circumference and the length of the femur or thigh bone.

Some conditions, including heart defects and bowel obstructions, may not be seen until later in your pregnancy. Having your anomaly scan will most likely rule out all these conditions, as the vast majority of babies are born healthy.

Other problems may mean a baby needs surgery or treatment after birth, or even surgery while still in the uterus. There will be a whole range of people to support you if there is a difficulty.

Consult your gynaecologist/midwife:
  • to refer you for an anomaly scan
  • for a second opinion, if a concern arose after an anomaly scan
  • to help you decide whether you require additional tests to assess baby
  • to help you decide what to do, in the unlikely event of there being a problem with baby.
At Elsbeth's Doctors our private consultant gynaecologists and obstetricians are specialists in fetal maternal medicine. Their experience includes working in a tertiary referral centre (where doctors refer at-risk pregnancies or where pregnant couples can go for a second opinion.) We offer the anomaly scan as part of a comprehensive package of care available to private patients or to couples who need help on a one-off basis. We will give you a copy of the "photo" of baby as a print-out and/or on a USB stick.