diff --git a/clinvar_this/io/tsv.py b/clinvar_this/io/tsv.py
index 5cffcb4..53dbfd8 100644
--- a/clinvar_this/io/tsv.py
+++ b/clinvar_this/io/tsv.py
@@ -692,6 +692,7 @@ def record_pubmed_citations(
                 )
                 for pmid in record.pmids
             ]
+        return None
 
     def record_clinical_features(
         record: SeqVarTsvRecord,
@@ -877,7 +878,8 @@ def _hpo_terms(submission: SubmissionClinvarSubmission) -> typing.Optional[typin
 
     def _pmids(submission: SubmissionClinvarSubmission) -> typing.Optional[typing.List[str]]:
         if citations := submission.clinical_significance.citation:
-            return [c.id for c in citations if c.db == CitationDb.PUBMED]
+            return [c.id for c in citations if c.db == CitationDb.PUBMED and c.id]
+        return None
 
     def submission_to_seq_var_tsv_record(
         submission: SubmissionClinvarSubmission,
@@ -976,7 +978,8 @@ def _inheritance(submission: SubmissionClinvarSubmission) -> typing.Optional[Mod
 
     def _pmids(submission: SubmissionClinvarSubmission) -> typing.Optional[typing.List[str]]:
         if citations := submission.clinical_significance.citation:
-            return [c.id for c in citations if c.db == CitationDb.PUBMED]
+            return [c.id for c in citations if c.db == CitationDb.PUBMED and c.id]
+        return None
 
     def submission_to_struc_var_tsv_record(
         submission: SubmissionClinvarSubmission,