Transient elastography detects liver fibrosis by estimating liver stiffness. It may show false high results when blood flow to the liver is increased, like during late stages of pregnancy. A study longitudinally evaluated transient elastography in healthy pregnant women.

24 healthy women with normal singleton pregnancies were enrolled for the study, who underwent transient elastography at gestational week 18–20, week 26–28 and week 36–38, and atleast after 8 weeks postpartum.

The following observations were made-

• Mean age at baseline was 30.6 years ± 4.1 
• Mean BMI at baseline was 22.3 kg/m2±1.9. 
• 58% of the women were nulliparous. 
• The pregnancy outcomes were found to be normal, describing no cases of preeclampsia or gestational diabetes. 
• Mean gestational length was 284 days ± 7. 
• Mean liver stiffness increased from 3.8 kPa to 5.9 kPa from the second trimester to the third trimester. 
• At the third trimester, 8% of women demosntrated an elastography measurement of >7.9 kPa. 
• liver stiffness decreased to early second trimester levels, Postpartum. (5.9 to 3.8 kPa,) 
• No woman showed liver stiffness values above 7.9 kPa Postpartum. 
• The mean Controlled Attenuation Parameter (CAP) increased from 186 dB/m to 215 dB/m from the second trimester to the third trimester.
• CAP also reversed postpartum (215 to 193 dB/m).

Thus, Liver stiffness and CAP increase reversibly during normal pregnancies, and little elevated levels in the third trimester can be regarded as a normal finding.

Source- Ribeiro MS, Hagström H, StÃ¥l P, Ajne G. Transient liver elastography in normal pregnancy – a longitudinal cohort study, Scandinavian Journal of Gastroenterology, 2019;54(6): 761-765. DOI: 10.1080/00365521.2019.1629007