diff --git a/polylabel.js b/polylabel.js
index 2cd4d51..4a4a368 100644
--- a/polylabel.js
+++ b/polylabel.js
@@ -129,8 +129,9 @@ function getCentroidCell(polygon) {
         y += (a[1] + b[1]) * f;
         area += f * 3;
     }
-    if (area === 0) return new Cell(points[0][0], points[0][1], 0, polygon);
-    return new Cell(x / area, y / area, 0, polygon);
+    const centroid = new Cell(x / area, y / area, 0, polygon);
+    if (area === 0 || centroid.d < 0) return new Cell(points[0][0], points[0][1], 0, polygon);
+    return centroid;
 }
 
 // get squared distance from a point to a segment