Netrin-1 is a secreted protein, which was first identified as a neuronal guidance factor. It is expressed in a multitude of tissues as pancreas, lung, breast, and placenta. Netrin-1 is a multifunctional protein, involved in cell polarity, adhesion, angiogenesis, apoptosis, migration, morphogenesis, and differentiation of various cell types. Most of netrin-1 activity occur through signaling pathways induced by its two main receptors, DCC (deleted in colorectal cancer) and UNC5H (uncoordinated-5 homolog). Its receptors have been linked to the processes of apoptosis and angiogenesis. In absence of netrin-1, DCC and UNC5H receptors lead to apoptosis. In contrary, in presence of netrin-1, receptors transduce molecular cascades leading to proliferation, differentiation and migration of the cells. Netrin-1 has been involved in the pathogenesis of multiple diseases, as diabetes, cardiovascular diseases, and cancer. Serum Netrin-1 levels were high in preeclamptic patients.

Inclusion Criteria:

• Age between 20-40 years.
• Singleton pregnancy.
• Women with suspicion of PA by two-dimensional (2D) gray scale imaging and color Doppler flow mapping

Exclusion Criteria:

• Multiple pregnancy,
• Fetal anomalies,
• Preterm premature rupture of membranes, or infection
• Any medical disorders, such as thyroid dysfunction, hypertension, and gestational diabetes
• Patients with known bleeding disorders or on anticoagulant therapy.