diff --git a/Cargo.lock b/Cargo.lock
index 0284f76..276cc8a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -471,6 +471,7 @@ dependencies = [
  "criterion",
  "ndarray",
  "rand",
+ "regex",
  "rstest",
 ]
 
diff --git a/phylo2vec/Cargo.toml b/phylo2vec/Cargo.toml
index 99f3a7b..dc694b6 100644
--- a/phylo2vec/Cargo.toml
+++ b/phylo2vec/Cargo.toml
@@ -8,6 +8,7 @@ license = "LGPL-3.0"
 
 [dependencies]
 rand = "*"
+regex = "1.11.1"
 
 [dev-dependencies]
 rstest = "0.23.0"
diff --git a/phylo2vec/src/tree_vec/ops/newick.rs b/phylo2vec/src/tree_vec/ops/newick/mod.rs
similarity index 61%
rename from phylo2vec/src/tree_vec/ops/newick.rs
rename to phylo2vec/src/tree_vec/ops/newick/mod.rs
index d7d8888..b776f42 100644
--- a/phylo2vec/src/tree_vec/ops/newick.rs
+++ b/phylo2vec/src/tree_vec/ops/newick/mod.rs
@@ -1,5 +1,9 @@
 use crate::tree_vec::types::Ancestry;
 
+mod newick_patterns;
+
+pub use newick_patterns::NewickPatterns;
+
 fn _get_cherries_recursive_inner(ancestry: &mut Ancestry, newick: &str, has_parents: bool) {
     let mut open_idx: usize = 0;
 
@@ -84,6 +88,30 @@ fn _build_newick_recursive_inner(p: usize, ancestry: &Ancestry) -> String {
     format!("({},{}){}", left, right, p)
 }
 
+pub fn remove_parent_labels(newick: &str) -> String {
+    let newick_patterns = NewickPatterns::new();
+    return newick_patterns.parents.replace_all(newick, ")").to_string();
+}
+
+pub fn has_parents(newick: &str) -> bool {
+    let newick_patterns = NewickPatterns::new();
+    return newick_patterns.parents.is_match(newick);
+}
+
+pub fn find_num_leaves(newick: &str) -> usize {
+    let newick_patterns = NewickPatterns::new();
+    let result: Vec<usize> = newick_patterns
+        .pairs
+        .captures_iter(newick)
+        .map(|caps| {
+            let (_, [_, node]) = caps.extract();
+            node.parse::<usize>().unwrap()
+        })
+        .collect();
+
+    return result.len();
+}
+
 /// Build newick string from the ancestry matrix
 pub fn build_newick(ancestry: &Ancestry) -> String {
     // Get the root node, which is the parent value of the last ancestry element
@@ -92,3 +120,48 @@ pub fn build_newick(ancestry: &Ancestry) -> String {
     // Build the Newick string starting from the root, and append a semicolon
     format!("{};", _build_newick_recursive_inner(root, ancestry))
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::tree_vec::ops::to_newick;
+    use crate::utils::sample;
+    use rstest::*;
+
+    #[rstest]
+    #[case("(((0,(3,5)6)8,2)9,(1,4)7)10;", "(((0,(3,5)),2),(1,4));")]
+    #[case("(0,(1,(2,(3,(4,5)6)7)8)9)10;", "(0,(1,(2,(3,(4,5)))));")]
+    #[case("((0,2)5,(1,3)4)6;", "((0,2),(1,3));")]
+    fn test_remove_parent_labels(#[case] newick: &str, #[case] expected: &str) {
+        let result = remove_parent_labels(&newick);
+        assert_eq!(result, expected);
+    }
+
+    #[rstest]
+    #[case(10)]
+    #[case(100)]
+    #[case(1000)]
+    fn test_has_parents(#[case] n_leaves: usize) {
+        let v = sample(n_leaves, false);
+        let newick = to_newick(&v);
+        // Check if the newick string has parents
+        let result = has_parents(&newick);
+        assert_eq!(result, true);
+
+        // Check if the newick string does not have parents
+        let result_no_parents = has_parents(&remove_parent_labels(&newick));
+        assert_eq!(result_no_parents, false);
+    }
+
+    #[rstest]
+    #[case(10)]
+    #[case(100)]
+    #[case(1000)]
+    fn test_find_num_leaves(#[case] n_leaves: usize) {
+        let v = sample(n_leaves, false);
+        let newick = to_newick(&v);
+        // Check if the newick string has parents
+        let result = find_num_leaves(&newick);
+        assert_eq!(result, n_leaves);
+    }
+}
diff --git a/phylo2vec/src/tree_vec/ops/newick/newick_patterns.rs b/phylo2vec/src/tree_vec/ops/newick/newick_patterns.rs
new file mode 100644
index 0000000..2922604
--- /dev/null
+++ b/phylo2vec/src/tree_vec/ops/newick/newick_patterns.rs
@@ -0,0 +1,30 @@
+#[derive(Debug)]
+pub struct NewickPatterns {
+    pub left_node: regex::Regex,
+    pub right_node: regex::Regex,
+    pub pairs: regex::Regex,
+    pub branch_lengths: regex::Regex,
+    pub parents: regex::Regex,
+}
+
+impl NewickPatterns {
+    pub fn new() -> Self {
+        let _left_node = r"\(\b(\d+)\b";
+        let _right_node = r",\b(\d+)\b";
+        let _branch_lengths = r":\d+(\.\d+)?";
+        let _parents = r"\)(\d+)";
+        let _pairs = format!(r"({})|({})", _left_node, _right_node);
+        NewickPatterns {
+            // Pattern of an integer label on the left of a pair
+            left_node: regex::Regex::new(&_left_node).unwrap(),
+            // Pattern of an integer label on the right of a pair
+            right_node: regex::Regex::new(&_right_node).unwrap(),
+            // Pattern of a pair of integer labels
+            pairs: regex::Regex::new(&_pairs).unwrap(),
+            // Pattern of a branch length annotation
+            branch_lengths: regex::Regex::new(&_branch_lengths).unwrap(),
+            // Pattern of a parent label
+            parents: regex::Regex::new(&_parents).unwrap(),
+        }
+    }
+}