Diagnostic Value of Serum Levels of Vascular Endothelial Growth Factor as a Marker of Tubal Pregnancy

Tubal pregnancy is a life threatening condition that not only causes mortality but also reduces fertility by less than 50%. In many patients, the level of βhCG does not reach detection threshold, and for definite diagnosis, long-term follow-up considering βhCG titration and transvaginal ultrasonography are needed which could lead to delay in diagnosis and treatment. The aim of this study was to determine the vascular endothelial growth factor (VEGF) levels as a serum biomarker in the diagnosis of tubal pregnancy.

This descriptive study was performed in 103 pregnant women attending Sari Imam Khomeini Hospital, 2018, of whom tubal pregnancy was diagnosed in 50 at 5 to 7.5 weeks of gestational age and the rest (n=53) had normal intrauterine pregnancy with the same gestational age. An ELISA kit (Bioassay Laboratory-China) was used to measure the levels of serum VEGF.

The patients aged 21 to 47 years old (mean age: 31.2 ± 6.1 years). The median serum levels of VEGF in the tubal pregnancy group and individuals with normal intrauterine pregnancy were 233.5 and 157.9, respectively, indicating significant differences between the two groups (P<0.0001). When threshold concentrations of a serum VEGF level > 280 pg/ml were used, tubal pregnancy could be distinguished from normal pregnancy with a sensitivity of 86%, specificity of 67.9%, positive predictive value of 99.6%, and positive and negative likelihood ratio of 2.68 and 0.21, respectively.

According to current findings, serum VEGF levels could be of great help in differentiating tubal pregnancy from normal pregnancy with appropriate sensitivity and specificity.