diff --git a/src/prevector.h b/src/prevector.h
--- a/src/prevector.h
+++ b/src/prevector.h
@@ -477,6 +477,22 @@
         fill(ptr, first, last);
     }
 
+    inline void resize_uninitialized(size_type new_size) {
+        // resize_uninitialized changes the size of the prevector but does not
+        // initialize it. If size < new_size, the added elements must be
+        // initialized explicitly.
+        if (capacity() < new_size) {
+            change_capacity(new_size);
+            _size += new_size - size();
+            return;
+        }
+        if (new_size < size()) {
+            erase(item_ptr(new_size), end());
+        } else {
+            _size += new_size - size();
+        }
+    }
+
     iterator erase(iterator pos) { return erase(pos, pos + 1); }
 
     iterator erase(iterator first, iterator last) {
diff --git a/src/serialize.h b/src/serialize.h
--- a/src/serialize.h
+++ b/src/serialize.h
@@ -772,7 +772,7 @@
     size_t i = 0;
     while (i < nSize) {
         size_t blk = std::min(nSize - i, size_t(1 + 4999999 / sizeof(T)));
-        v.resize(i + blk);
+        v.resize_uninitialized(i + blk);
         is.read((char *)&v[i], blk * sizeof(T));
         i += blk;
     }
@@ -789,8 +789,8 @@
         if (nMid > nSize) {
             nMid = nSize;
         }
-        v.resize(nMid);
-        for (; i < nMid; i++) {
+        v.resize_uninitialized(nMid);
+        for (; i < nMid; ++i) {
             Unserialize(is, v[i]);
         }
     }
diff --git a/src/test/prevector_tests.cpp b/src/test/prevector_tests.cpp
--- a/src/test/prevector_tests.cpp
+++ b/src/test/prevector_tests.cpp
@@ -176,6 +176,26 @@
         pre_vector = pre_vector_alt;
     }
 
+    void resize_uninitialized(realtype values) {
+        size_t r = values.size();
+        size_t s = real_vector.size() / 2;
+        if (real_vector.capacity() < s + r) {
+            real_vector.reserve(s + r);
+        }
+        real_vector.resize(s);
+        pre_vector.resize_uninitialized(s);
+        for (auto v : values) {
+            real_vector.push_back(v);
+        }
+        auto p = pre_vector.size();
+        pre_vector.resize_uninitialized(p + r);
+        for (auto v : values) {
+            pre_vector[p] = v;
+            ++p;
+        }
+        test();
+    }
+
     ~prevector_tester() {
         BOOST_CHECK_MESSAGE(passed, "insecure_rand: " + rand_seed.ToString());
     }
@@ -257,6 +277,14 @@
             if (InsecureRandBits(5) == 18) {
                 test.move();
             }
+            if (InsecureRandBits(5) == 19) {
+                unsigned int num = 1 + (InsecureRandBits(4));
+                std::vector<int> values(num);
+                for (auto &v : values) {
+                    v = InsecureRand32();
+                }
+                test.resize_uninitialized(values);
+            }
         }
     }
 }