Antenatal screening test

At the first visit we perform or your General practitioner would have carried out these tests before you have seen us

  • Full blood count (FBC)
  • Blood group/ Rh type/ antibodies
  • Rubella serology
  • Hepatitis B/ hepatitis C/ HIV/ Syphilis serology
  • Thyroid function test
  • Serum Vitamin D levels
  • Mid stream urine culture

The screening tests for Down’s syndrome , trisomy 13 and trisomy 18 are performed by doing maternal serum test at 11 weeks gestation and then an ultrasound scan looking at the nuchal translucency at 12 weeks gestation. Using age alone, the sensitivity for detecting Down syndrome is 30 per cent. Using nuchal translucency, the sensitivity is 90 per cent.

A foetal anomaly scan is performed at 19 – 20 weeks gestation and you will be referred to an Ultrasound place for this.

Between 24 and 28 weeks gestation, a glucose tolerance test is done to diagnose gestational diabetes and a FBC/ antibody screen.

If you are Rh negative blood group you will be given an anti D injection at 28 and 34 weeks with your consent.

At 36 weeks gestation, a vaginal swab is taken to assess colonization with Group B Streptococcus and if positive you will be given treatment with intravenous antibiotics during labour to prevent infection to the baby.