Regarding placental growth factor (PlGF) testing in suspected pre-eclampsia before 35 weeks, a PlGF result below which threshold is used to 'rule in' significant placental dysfunction according to the PARROT trial?

• A Below 50 pg/mL
• B Below 12 pg/mL ✓
• C Below 100 pg/mL
• D Below 200 pg/mL

Explanation

The PARROT trial (2019, UK) evaluated PlGF-based testing in women with suspected pre-eclampsia at 20–36+6 weeks. A PlGF below 12 pg/mL identifies women at high risk of severe placental disease and the need for delivery within 14 days. The PARROT trial showed that PlGF-based testing reduced severe maternal adverse outcomes compared to standard care. PlGF below 12 pg/mL is the 'rule in' threshold; 12–100 pg/mL is intermediate.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.