{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T09:37:42Z","timestamp":1788514662551,"version":"build-2803163510"},"reference-count":37,"publisher":"Walter de Gruyter GmbH","issue":"3","license":[{"start":{"date-parts":[[2025,12,29]],"date-time":"2025-12-29T00:00:00Z","timestamp":1766966400000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,3,26]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec id=\"j_jpm-2025-0279_abs_001\">\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>Historically, baseline fetal heart rate variability (FHRV) with an amplitude of greater than 25 beats per minute, and lasting for more than 30\u202fmin, was defined as the saltatory pattern. Several experimental animal models have reported an association between saltatory pattern and poor perinatal outcomes. However, recent studies have suggested that the classically defined saltatory pattern is very uncommon during labor, and a new CTG pattern, called the \u201cZigZag\u201d pattern (ZZP), has been reported. ZZP has been defined as a rapid, erratic repetitive oscillations in the FHR with an amplitude of &gt;25\u202fbpm and has been claimed as a potential marker to identify fetuses at risk of intra-partum and perinatal compromise during labour. A recent international expert consensus has recommended that ZZP persisting for &gt;1\u202fmin requires an urgent intervention to avoid poor perinatal outcomes. The aim of the present systematic review was to determine the intra-partum and perinatal outcomes of fetuses with the ZZP compared to the control group not showing the ZZP during\u00a0labor.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"j_jpm-2025-0279_abs_002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Medline, Embase and Cochrane databases were searched. Inclusion criteria were studies reporting the intra-partum and perinatal outcome of fetuses showing compared to those not showing ZZP during labour. The outcomes observed were operative vaginal delivery, caesarean section, umbilical artery pH&lt;7.1, base excess &lt;\u221211, mean pH\u00a0and base excess, admission to neonatal intensive care unit (NICU), abnormal post-natal brain imaging and occurrence of late decelerations later on the CTG trace. Random-effect meta-analyses were used to combine data and results reported as pooled odd ratios (OR) for categorical and pooled mean differences (MD) for continuous variables with their 95\u202f% confidence intervals\u00a0(CI).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"j_jpm-2025-0279_abs_003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Six studies (18,136 fetuses) were included. Fetuses showing ZZP on CTG trace during labor had a higher risk of operative vaginal delivery (OR: 2.22, 95\u202f% CI 1.69\u20132.91; p&lt;0.001), cesarean delivery (OR: 1.71, 95\u202f% CI 1.37\u20132.15; p&lt;0.001), umbilical artery pH&lt;7.1 (OR: 2.48, 95\u202f% CI 1.56\u20133.94; p&lt;0.001), Apgar score &lt;7 at 5\u202fmin (OR: 2.13, 955 CI 1.05\u20134.31; p=0.004) and the occurrence of late decelerations later on during labor (OR: 9.51, 95\u202f% CI 7.80\u201311.61; p&lt;0.001) compared to those not showing this pattern, while there was no difference in the risk of NICU admission (p=0.209) and respiratory support after birth (p=0.755). Likewise, umbilical artery pH\u00a0was significantly lower in fetuses showing compared to those not showing ZZP during labour (pooled MD:\u00a0\u22120.10, 95\u202f% CI\u00a0\u22120.11 to\u00a0\u22120.09; p&lt;0.001), while there was no difference in the value of mean base excess between the two groups (p=0.156).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"j_jpm-2025-0279_abs_004\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Fetuses showing the ZZP on CTG trace during labour are at higher risk of operative vaginal delivery, caesarean section and adverse intrapartum and perinatal outcomes.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1515\/jpm-2025-0279","type":"journal-article","created":{"date-parts":[[2025,12,27]],"date-time":"2025-12-27T06:02:06Z","timestamp":1766815326000},"page":"566-574","source":"Crossref","is-referenced-by-count":2,"title":["Intra-partum and perinatal outcomes in fetuses exhibiting ZigZag pattern on cardiotocography trace: a systematic review and meta-analysis"],"prefix":"10.1515","volume":"54","author":[{"given":"Luca","family":"Finadri","sequence":"first","affiliation":[{"name":"Centre for Fetal Care and High-Risk Pregnancy, University of Chieti , Chieti , Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9866-3050","authenticated-orcid":false,"given":"Ilenia","family":"Mappa","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology , Policlinico Umberto I , Rome , Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Asma","family":"Khalil","sequence":"additional","affiliation":[{"name":"Fetal Medicine Unit, St George\u2019s University Hospital , London , UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5525-4353","authenticated-orcid":false,"given":"Giuseppe","family":"Rizzo","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology , Policlinico Umberto I , Rome , Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro","family":"Lucidi","sequence":"additional","affiliation":[{"name":"Centre for Fetal Care and High-Risk Pregnancy, University of Chieti , Chieti , Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6560-3393","authenticated-orcid":false,"given":"Daniele","family":"Di Mascio","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology , Policlinico Umberto I , Rome , Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marco","family":"Liberati","sequence":"additional","affiliation":[{"name":"Centre for Fetal Care and High-Risk Pregnancy, University of Chieti , Chieti , Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Edwin","family":"Chandraharan","sequence":"additional","affiliation":[{"name":"Department of Transformational Learning & Development , Global Academy of Medical Education & Training , London , UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesco","family":"D\u2019Antonio","sequence":"additional","affiliation":[{"name":"Centre for Fetal Care and High-Risk Pregnancy, University of Chieti , Chieti , Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"374","published-online":{"date-parts":[[2025,12,29]]},"reference":[{"key":"2026051215133581972_j_jpm-2025-0279_ref_001","doi-asserted-by":"crossref","unstructured":"Steer, PJ. 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