10 Dec

An improved labor curve tool

Last week’s webinar, covering research on a new method to assess labor progress, continues to stimulate comment and debate. The session described a whole new labor curve concept, one that adapts to the multiple factors affect dilation directly and change as labor advances. Recent peer reviewed publications report a five-fold improvement in the rate of identification of first time mothers who actually underwent a cesarean for slow labor using the PeriCALM Curve compared to the rate using the current fixed labor curves that are based on time only (70% vs 12%).

The research, outlined in two articles recently published in the American Journal of Obstetrics & Gynecology, was reviewed by Dr. Emily Hamilton during a lunchtime session offered by PeriGen. The session, titled “Rethinking the Labor Curve,” was recorded and can be viewed here.

Dr. Hamilton led the research team that applied a modern, mathematical approach to the assessment of labor. The team found that the utility of contemporary labor curves was limited because of, among other things, a wide degree of variation in the early stages of labor. In fact, it is not until late labor when dilation reaches six centimeters that this variation enters useful limits and the contemporary curves can be used. The new approach can be applied earlier to assess two essential processes for vaginal birth (dilatation and descent). Results are expressed with percentiles and graphs.

The video, access to the basic research, and the slides are available by clicking here.

We look forward to hearing your thoughts and questions too.

18 Nov

PeriGen Research Article Count Up to 51

PeriGen RessearchWith the addition of two new research articles on the labor curve —  published in the American Journal of Obstetrics & Gynecology, PeriGen-related research publications now total 51.

The two new articles are titled:

The clinical research team, led by Emily Hamilton MDCM, have authored and co-authored numerous articles related to their pattern-recognition, labor curve management, protocol management tools, and electronic fetal monitoring.

Included in the extensive list are several that are of special interest to labor & delivery clinicians:

Elliott C, Warrick P, Graham E, Hamilton E:   Graded Classification of Fetal Heart Rate Tracings: Association with Neonatal Metabolic Acidosis and Neurologic Morbidity.     Am J Obstet Gynecol. 2010 Mar;202(3):258.e1-8. Epub2009 Aug 29.

Parer JT, Hamilton EF:   Comparison of Five Experts in Computer Analysis in Rule-Based Fetal Heart Rate Interpretation.   Am J Obstet Gynecol. 2010 Nov;203(5):451.e1-7. Epub 2010Jul 15.

Hamilton E, Warrick P, O’Keeffe D:   Variable Decelerations: Do Size and Shape Matter? J Matern Fetal Neonatal Med. 2012 Jun25;(6):648-653.

Hamilton E, Warrick P, Knox E, O’Keeffe D, Garite T:   High uterine contraction rates in births with normal and abnormal umbilical artery gases. J Matern Fetal Neonatal Med. 2012 Nov;25(11):2302-7.

Daly MV, Bender C, Townsend KE, Hamilton EF:   Outcomes associated with a structured prenatal counseling program for shoulder dystocia with brachial plexus injury.   Am J Obstet Gynecol. 2012 Aug;207(2):123.e1-5. doi: 10.1016/j.ajog.2012.05.023. Epub 2012 Jun 1

Hamilton EF, Warrick PA:   New perspectives in electronic fetal surveillance. J Perinat Med. 2013 Jan;41(1):83-92.

Smith S, Zacharias J, Lucas V, Warrick PA, Hamilton EF. Clinical associations with uterine tachysystole. J Matern Fetal Neonatal Med. 2014 May;27(7):709-13.

Click to review the complete list

21 Sep

Fetal Heart Rate Physiology Paper

Fetal Heart Rate Physiology Paper

New White Paper Now Available:

The Physiology of the Fetal Heart Rate Control

Dr. Emily Hamilton, PeriGen’s Senior Vice President of Clinical Research, has just posted a new white paper covering the basic physiology of the fetal heart rate (FHR). Ideal for perinatal unit managers and educators looking for information to help their labor & delivery teams understand how electronic fetal monitoring can help identify fetuses with an increased risk of hypoxic injury and the basis of clinical interpretation of tracings as delivered via EFM and perinatal analysis.  The 15-page paper delves into the impact of active labor on the FHR and the researched clinical models used to differentiate between normal and abnormal FHR patterns.

The paper’s references span a wide variety of research on fetal heart rate and its measurement during labor.  Content includes:

Click for complimentary access to “The Physiology of the Fetal Heart Rate”

About the Author

Emily Hamilton, MDCM is PeriGen’s Senior Vice President of Clinical Research and the inventor of the PeriCALM suite of perinatal analysis software.  She and her research team actively engage in research projects designed to develop and improve the mathematical  models used by PeriCALM software to detect and alert on potentially harmful FHR patterns.

She is widely published in leading obstetric journals and often speaks on her research and the use of technology to help labor & delivery clinical teams identify abnormal fetal heart rate patterns during childbirth.  In addition to being an experienced obstetrician, Emily held numerous academic positions at McGill University.  She works and resides in Montreal, Canada.

14 Sep

UCSF, Kaiser Permanente and PeriGen to research birth-related brain injury

PeriGen has joined the University of California, San Francisco and Kaiser Permanente North California to launch a ground-breaking research project to examine potentially preventable causes of birth-related brain injuries in newborns.  The project looks to deepen understanding of how fetal heart rate and uterine contraction patterns indicate risk to the baby during labor in order to help improve clinicians ability to prevent brain damage.

“This project has the potential to make a significant contribution to unraveling some of the preventable causes of a condition that is devastating for far too many babies and their families,” says Matthew Sappern, PeriGen’s Chief Executive Officer.

The collaborative research project among these three highly respected organizations will study the relationship of neonatal encephalopathy and overly frequent uterine contractions and fetal heart rate abnormalities within a large birth cohort delivered by Kaiser Permanente Northern California OB physicians.

Neonatal encephalopathy is a clinically-defined syndrome characterized by disturbed neurologic function in the earliest days of life.  It can lead to lifelong impairment or cerebral palsy, depending on the severity.

Continue reading

22 Jan

Oxytocin Case Study Available

EmilyHamilton - GTWThe Journal of Healthcare Information Management has just published an article co-authored by PeriGen’s Emily Hamilton highlighting how administration of oxytocin was improved through the use of electronic fetal monitoring. Click to access


Smith S, Bunting K, Hamilton E. Using Intelligent Electronic Fetal Monitoring Software to Reduce Iatrogenic Complications of Childbirth. JHIM. 28; 4:28-33.

11 Dec

What Have We Learned & Where Are We Going?

by Emily Hamilton, MDCM
Senior Vice President, Clinical Research, PeriGen

“In the New Year, you carry all the experiences of the past years and that is the greatest power of every New Year! This year, you are less student and more master!”
~Mehmet Murat Ildan, Contemporary Novelist & Playwright


Flling rates of intrapartum-related neonatal encephalopathy

Figure 1. Falling rates of intrapartum-related neonatal encephalopathy

Just as individuals gain experience and wisdom on life’s journey, so do organizations, professions and companies. Experience helps because as professionals we are entrusted with responsibility both at a personal and organizational level to provide safe maternity care. Among the myriad of challenges crying for our attention, which ones are critical, have a chance for success, or bring the greatest benefit for our mothers, babies and their families? With the New Year beginning it is time to pause and reflect on some of the lessons learned and past accomplishments because they will help us plan our journey for the coming year. As you read on, note the clarity of insights gained by using “Big Data” and “Wide Lenses” for time and geography.

One of the United Nation’s Millennium Goals – to reduce child mortality, has brought us more reliable data on an important obstetrical topic: namely, intrapartum-related neonatal encephalopathy (IP-NE). On a world scale, intrapartum-related hypoxic events are estimated to have a huge impact – contributing to ¼ of neonatal deaths and ½ of late pregnancy stillbirths. They make the largest single-condition contribution to disability adjusted life-years. 1-4

When one examines progress over 20 years in multiple countries, steady incremental improvement is evident. Figure 1 shows the falling rates of IP-NE in regions including and most similar to the US1 Rates in all the other geographical regions were much higher. They all showed progressive descent fell except for the region of Sub-Saharan Africa.

Two other recent and large studies provide further important insights regarding the nature of IP-NE and related clinical care. 5, 6 Researchers in Sweden, where infant mortality rates are generally amongst the best in the world, examined 71,189 birth records to investigate the association between EFM patterns and neonatal outcome. 5 The rates of neonatal encephalopathy were very low at 1.1 per 1000 births. They concluded that moderate and severe encephalopathy was attributable to asphyxia in 60% of their NE cases and most evolved during labor.

Moving closer to home, Clark et al examined the effect of compliance vs non-compliance with an oxytocin administration protocol in 14,398 women undergoing induction of labor at HCA.6 Oxytocin misuse is a common finding in births with severe metabolic acidosis. 7-9 Furthermore, oxytocin misuse is a modifiable risk factor. In this most recent study compliance was associated with:

  • Fewer admissions to the NICU (3.8% vs  5.2% P=0.01)
  • Fewer low Apgar scores (4.9% vs 6.4% P=0.04)
  • Fewer cesareans     (15.8% vs 18.8% P<0.01)
Figure 2. PeriCALM Patterns display showing the analysis related to uterine tachysystole.

Figure 2. PeriCALM Patterns display showing the analysis related to uterine tachysystole

Members of our own PeriGen family have experienced similar success stories. 10 MedStar Franklin Square Medical Center launched a highly successful IT initiative focusing on uterine tachysystole (overly frequent contractions). PeriCALM Patterns fetal monitoring software with built-in pattern recognition and specialized long-term graphical displays was introduced in 2011. At a glance any clinician could detect if uterine tachysystole (UT) was present, if it was transient or persistent, if it provoked fetal heart rate decelerations and see the Montevideo units as is shown in Figure 2.

This study involved the systematic re-examination of each 30-minute segment of tracing from all 10,518 monitored term labors. Comparing years before immediately before and after the introduction of PeriCALM Patterns they observed that:

  • The rate of UT with oxytocin fell from 22.7% to 17.3% P<0.0001.
  • Average duration of UT fell from 64 minutes to 54 minutes.
  • Total time spent in UT fell by 36.5%.

Long term trends analysis is a key component of helping humans see significant trends and to anticipate what is about to happen. In psychological parlance this ability to assess current conditions and project the most likely development is known as situational awareness. In medical behavioral studies it is one of the key skills required across all acute care settings.

Computers are masters of rapid computation and efficient data visualization. Anecdotes from nursing staff related how the displays made easy it was to see when uterine tachysystole was present or even about to occur. Continuous calculations removed the subjectivity of choosing where to count the contraction rates. Quantitative data facilitated communication because predominant patterns were clearly evident. Nurses had the authority to stop oxytocin when uterine tachysystole occurred.

There is abundant evidence today that the human brain has a fixed functional capacity and that every mental task we perform detracts from our ability to do another at the same time. 11 Computers are very consistent at number crunching, that is counting, adding, measuring or doing exactly what they are programmed to do. In contrast, humans are very good at reasoning based on deep clinical understanding Clinicians will always have to integrate EFM tracing findings with other clinical information. That said, the repetitive analytic capacity of PeriCALM Patterns and its long-term displays are useful adjuncts for clinicians. This study demonstrated the synergistic effects of this technology and dedicated clinicians. Together they achieved an impressive reduction in UT.

In summary, what lessons have we learned?

Lesson 1. It is impossible to see progress in rare conditions using small samples over short periods of time.  Rates derived from large data sets and trends over long periods are much more revealing.

Lesson #2. A substantial portion of NE arises and evolves during labor.

Lesson #3.  The incidence of intrapartum-related NE, a devastatingly serious condition, is falling.

Lesson #4.  Clinical actions matter. Oxytocin protocol compliance is associated with better neonatal condition and lower cesarean rates. Uterine tachysystole rates can be reduced.

Lesson #5.  Computers and clinicians can be highly synergistic.

No one is suggesting that technology replace clinicians. However, computerization is useful for tasks like calculations, data visualization, reminders and communication thus freeing clinicians to focus applies their energy on higher level reasoning and clinical interventions.

Maternal child health care has come a very long way. Detractors of EFM often refer to randomized clinical trials conducted more than 30 ago that showed no neonatal survival benefit with EFM, although EFM use was associated with a substantial reduction in the incidence of neonatal seizures. In the largest of these studies, deaths or seizures occurred at an astonishing rate of 1 in 225.12 Today, intrapartum fetal death is exceedingly rare and moderate and severe IP-NE are estimated to occur in approximately 1.5/1000 births among the High-Income countries and 0.6/1000 specifically in the Swedish study. This achievement did not happen by chance. Concerted efforts on many fronts have contributed. It happened in part, because most clinicians did not adopt a defeatist attitude such as believing that the origins of IP-NE were beyond our influence or that EFM held no value. Rather these clinicians continued to find better ways to fine tune the imperfect tools that are available and improve our health care systems.

Healthcare informatics has also evolved. We have seen a maturation of software for basic hospital wide electronic medical records and convergence on a few products. With this accomplishment we have seen an increasing demand for the efficient overlay of smart modules with real clinical benefits. In parallel, the PeriGen experience has confirmed our belief that the most useful smart software applications are those that harness the power of computers to do what they do best especially in areas that humans find challenging or time consuming.

As for the New Year, we will continue to apply sound analytical methods on high impact clinical issues where objective quantitative analysis helps clinicians see critical factors or developing trends and intervene in a timely fashion. We have reached a new level in medical informatics and a very exciting one indeed. Stay tuned as we work to bring these ideas to the bedside.


1. Lee AC, Kozuki N, Blencowe H, Vos T, Bahalim A, Darmstadt GL, Niermeyer S, Ellis M, Robertson NJ, Cousens S, Lawn JE. Intrapartum-related neonatal encephalopathy incidence and impairment at regional and global levels for 2010 with trends from 1990. Pediatr Res. 2013 Dec;74 Suppl 1:50-72. doi: 10.1038/pr.2013.206.

2. Wn J, Shibuya K, Stein C. No cry at birth: global estimates of intrapartum stillbirths and intrapartum-related neonatal deaths. Bull World Health Organ. 2005 Jun;83(6):409-17. Epub 2005 Jun 17.

3. Lawn JE, Lee AC, Kinney M, Sibley L, Carlo WA, Paul VK, Pattinson R, Darmstadt GL. Two million intrapartum-related stillbirths and neonatal deaths: where, why, and what can be done? Int J Gynaecol Obstet. 2009 Oct;107 Suppl 1:S5-18, S19. doi: 10.1016/j.ijgo.2009.07.016

4. Murray CJ, Lopez AD. Global mortality, disability, and the contribution of risk factors: Global Burden of Disease Study. Lancet. 1997 May 17;349(9063):1436-42.

5. Jonsson M, Agren J, Nordén-Lindeberg S, Ohlin A, Hanson U. Neonatal encephalopathy and the association to asphyxia in labor. Am J Obstet Gynecol. 2014 Dec;211(6):667.e1-8. doi: 10.1016/j.ajog.2014.06.027. Epub 2014 Jun 17.

6. Clark SL, Meyers JA, Frye DK, Garthwaite T, Lee AJ, Perlin JB. Recognition and response to electronic fetal heart rate patterns – impact on newborn outcomes and primary cesarean delivery rate in women undergoing induction of labor. Am J Obstet Gynecol. 2014 Nov 22. pii: S0002-9378(14)02249-2. doi: 10.1016/j.ajog.2014.11.019. [Epub ahead of print]

7. Clark SL, Belfort MA, Dildy GA, Meyers JA. Reducing obstetric litigation through alterations in practice patterns.  Obstet Gynecol. 2008 Dec;112(6):1279-1283.
8. Berglund S, Grunewald C, Pettersson H, Cnattingius S. Severe asphyxia due to delivery-related malpractice in Sweden 1990-2005. BJOG. 2008 Feb;115(3):316-323.

Jonsson M, Nordén SL, Hanson U. Analysis of malpractice claims with a focus on oxytocin use in labour. Acta Obstet Gynecol Scand. 2007;86(3):315-319.

10. Smith S, Bunting K, Hamilton E. Using Intelligent Electronic Fetal Monitoring Software to Reduce Iatrogenic Complications of Childbirth: A Case Study.J Healthc Inf Manag, in press

10. Rock D., Your Brain at Work: Strategies for Overcoming Distraction, Regaining Focus, and Working Smarter All Day Long Harper Business. Harper Collins, New York, NY.

12. MacDonald D, Grant A, Sheridan-Pereira M, Boylan P, Chalmers I. The Dublin randomized controlled trial of intrapartum fetal heart rate monitoring. Am J Obstet Gynecol. 1985 Jul 1;152(5):524-39

13 Jun

High uterine contraction rates in births with normal and abnormal umbilical artery gases

Emily F. Hamilton, Philip Warrick, G. Eric Knox, Daniel O’Keeffe, Thomas J. Garite


Objective: To determine if the incidence of high contraction (HC) rates and associated decelerations were different in term births with metabolic acidemia (MA) compared to those with normal gases (N) over the last 4 h of labor.

Methods: MA included 316 babies with cord base deficits (BD) over 12 mmol/L N – 3,320 babies with BD under 8 mmol/L. HC rates were defined as >5/10 min.

Results: One or more episodes of HC occurred in 43.7% of MA and 36.6% of N. (p = 0.015) In both groups the HC rates rose from about 1 in 30 patients at the beginning to 1 in 7 to 9 patients at the end. MA showed a different transition of the deceleration response over time. At the beginning the average ratio of decelerations to uterine contractions was similar in both groups but over the final 140 min MA showed a consistently higher ratio.

Conclusions: Although HC rates were more frequent in the MA, it was not uncommon in N. On average MA showed more decelerations at every level of contractions and had a persistently higher level of decelerations per contraction for more than 2 h before birth.


Cite this article as: Hamilton E, Warrick P, Knox E, Keeffe,DO, and Garite T. High uterine contraction rates in births with normal and abnormal umbilical artery gases. J Maternal Fetal Neonatal Med. 2012 Jun 13.

04 Jun

Outcomes associated with a structured prenatal counseling program for shoulder dystocia with brachial plexus injury

Mary Veronica Daly, MD, Christina Bender, MSN, Kathryn E. Townsend, JD, Emily F. Hamilton, MD


Objective: We examined outcomes associated with a novel program to identify patients at high risk for shoulder dystocia (SD) with BPI.

Study Design: The program included a checklist of key risk factors and a multifactorial algorithm to estimate risk of SD with BPI. We examined rates of cesarean and SD in 8,767 deliveries by clinicians enrolled in the program and in 11,958 patients of clinicians without access to program.

Results: Key risk factors were identified in 1,071/8767(12.2%) of mothers of whom 40/8767(0.46%) obtained results in the high risk category. The rate of primary cesarean rate was stable (21.2% to 20.8% P= 0.57). SD rates fell by 56.8%. (1.74% to 0.75% P=0.002). The rates of SD and cesarean birth showed no changes in the group without access to the program.

Conclusions: With the introduction of this program, overall SD rates fell by more than half with no increase in the primary cesarean rate.

Cite this article as: Daly M, Bender C, Townsend K, and Hamilton E. Outcomes associated with a structured prenatal counseling program for shoulder dystocia with brachial plexus injury. AJOG 2012 June 04.

Full Article

01 Sep

Implementation of a System-Wide Policy for Labor Induction

Publication: MCN, Maternal-Child Nursing
Date: September/October 2011
Author: P. Terrence O’Rourke, MD, FACS, Gerald J Girardi, MD, FACOG, Thomas N Balaskas, MD, FACOG, Rebecca A Havlisch, JD, RN, Gay Landstrom, MS, RN, Beth Kirby, MSHL, CPHRM G. Eric Knox, MD, and Kathleen Rice Simpson, PhD, RNC, FAAN


Standardization of key clinical protocols and policies in the inpatient obstetric setting has the potential to improve care processes, ultimately resulting in better patient outcomes and decreased professional liability. Increasingly hospitals and healthcare systems are realizing benefits with adoption of standardization as a strategy for quality care improvement. We describe successful system-wide development and implementation of a policy for labor induction including avoidance of elective births before 39 completed weeks of gestation and standardization of various aspects of the labor induction process, with the goal of providing safer care. Key Words: Elective labor induction; High-alert medication; Oxytocin; Perinatal patient safety; Standardization.

Full Article

26 Jul

Shoulder Dystocia: Neither Predictable nor Preventable? Not Anymore!

In the Summer, 2011 issue of MD Advisor, MD Advantage shares the results of a three-year trial of the PeriCALM® Shoulder Screen™ tool, a web-based application to identify mothers at greatest risk of shoulder dystocia. Using PeriCALM Shoulder Screen, MD Advantage’s insured physicians were able to reduce the incidence of shoulder dystocia by 50%, with no increase in the primary cesarean rate– disproving the myth that shoulder dystocia is an unpredictable and unpreventable occurrence. The article, “Shoulder Dystocia: Neither Predictable nor Preventable? Not Anymore!” is based on an interview with Emily Hamilton, MD, SVP of Clinical Research at PeriGen, Mary Veronica Daly, MD, Practicing Obstetrician at Lifeline Medical Group and Atlantic Health, and Robert B. Goley, SVP of Claims and Risk Management at MD Advantage.

Click here to read the rest of this article.

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