Association between PAPP-A and placental thickness

Measuring of maternal serum pregnancy-associated plasma protein-A (PAPP-A) in first trimester can be a way for early detection of adverse prenatal outcome due to faulty placenta.

The aim was to Determination of association between placental thickness in second trimester with low level of PAPP-A in first trimester.

In this cohort study, serum PAPP-A of 187 pregnant women was measured in the first trimester of pregnancy. Patients who had PAPP-A ≤0.8 MOM were in exposed and others who had PAPP-A >0.8 defined as unexposed group. The criteria of placental thickness in ultrasound study was thickness of 4 cm or more than 50% of placental length.

Of 187 patients, 87 patients had PAPP-A >0.8 and 93 patients had PAPP-A ≤0.8. Women with low levels of PAPP-A in the first trimester, had an increased incidence placental thickness of 34.4%, whereas another group had about 15% (p=0.002). Also, PAPP-A levels had acceptable sensitivity and specificity for placental thickness detection (71.1% and 54.8%, respectively.

Our study showed that serum level of PAPP-A generally was low (≤0.8) in women with a thick placenta (>4 cm or >50% of placental length). The first trimester of pregnancy measurement of PAPP-A will be more predictable for healthy placenta.