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Aiob A, Toma R, Wolf M, Haddad Y, Odeh M. Cerebroplacental ratio and neonatal outcome in low-risk pregnancies with reduced fetal movement: A prospective study. Eur J Obstet Gynecol Reprod Biol X 2022; 14:100146. [PMID: 35308423 PMCID: PMC8927905 DOI: 10.1016/j.eurox.2022.100146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 03/02/2022] [Accepted: 03/08/2022] [Indexed: 12/03/2022] Open
Abstract
Objective To evaluate the effectiveness of the cerebroplacental ratio (CPR) in predicting poor outcomes in low-risk pregnancies with reduced fetal movements (RFMs). Study Design This prospective study included singleton pregnancies at 28–40 weeks, presenting with RFM but no additional risk factors. Sub analysis was performed for pregnancies between 36 and 40 weeks. Umbilical artery (UA) and middle cerebral artery (MCA) pulsatility indices (PIs) were measured, and the MCA-PI to UA-PI ratio (CPR) was calculated. Mode of delivery, gestational age, fetal monitoring category, Apgar score at 1 and 5 min, birth weight, presence of meconium, umbilical artery pH, and neonatal intensive care unit (NICU) admission were recorded. Women with good and poor outcomes were compared with doppler indices and pregnancy characteristics. Results Of 96 women, 86 had good outcomes. There was no significant difference in UA-PI (0.871 ± 0.171 vs. 0.815 ± 0.179, P = 0.446), MCA-PI (1.778 ± 0.343 vs. 1.685 ± 0.373, P = 0.309), or CPR (2.107 ± 0.635 vs. 2.09 ± 0.597, P = 0.993) between the poor and good outcome groups. No difference was found in the location of the placenta, biophysical profile (BPP) score, fetal sex, or amniotic fluid index (AFI) at the time of presentation. The proportion of nulliparous patients in the poor outcome group was higher than that of multiparous patients. Sub analysis for 36–40 weeks revealed the same results; no significant difference in UA-PI (0.840 ± 0.184 Vs 0.815 ± 0.195, P = 0.599), MCA-PI (1.724 ± 0.403 vs. 1.626 ± 0.382, P = 0.523), or CPR (2.14 ± 0.762 vs. 2.08 ± 0.655, P = 0.931) between poor and good outcome groups. Conclusions CPR is not predictive of neonatal outcome in low-risk pregnancies with RFM. However, a higher proportion of poor outcomes in nulliparous women warrants further investigation.
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Affiliation(s)
- Ala Aiob
- Department of Obstetrics and Gynecology, Galilee Medical Center, Nahariya 22100, Israel
- Azrieli Faculty of Medicine, Bar Ilan University, Safed 52000, Israel
- Correspondence to: Department of Obstetrics and Gynecology, Galilee Medical Center, POB 22, Nahariya 22100, Israel.
| | - Ruba Toma
- Department of Obstetrics and Gynecology, Galilee Medical Center, Nahariya 22100, Israel
| | - Maya Wolf
- Department of Obstetrics and Gynecology, Galilee Medical Center, Nahariya 22100, Israel
- Azrieli Faculty of Medicine, Bar Ilan University, Safed 52000, Israel
| | - Yosef Haddad
- Department of Obstetrics and Gynecology, Galilee Medical Center, Nahariya 22100, Israel
| | - Marwan Odeh
- Department of Obstetrics and Gynecology, Galilee Medical Center, Nahariya 22100, Israel
- Azrieli Faculty of Medicine, Bar Ilan University, Safed 52000, Israel
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Abstract
Introduction: Counting of fetal movement (FM) during pregnancy is believed to be a method by which a woman estimates the fetal well-being. In 2015, it was estimated that 2.6 million babies had died in utero. A percentage of 30-55% of women who experience an episode of reduced fetal movement (RFM) within a week may face stillbirth. Aim: The aim of this review was to assess the impact of reduced fetal movements and of educational interventions on maternal counting of fetal movements on perinatal mortality, perinatal outcome and mode of delivery. Methods: A search of electronic databases was conducted for detecting studies that examine the coincidence of reduced fetal movements (RFM) in combination with stillbirth and perinatal morbidity. Results: The findings of this review suggest that there is an association between the incidence of stillbirth and the experience of alterations in fetal movements’ quantity and quality in the preceding weeks. Interventions on fetal movement counting, concerning both the number and the density of fetal movements, may reduce the adverse perinatal outcomes to an extent, after informing and making aware of the pregnant women for their meaning. Conclusion: Maternity care professionals should: a) inform pregnant women about the importance of FM counting, b) encourage pregnant women to be familiarized on the recognition of theirs’ baby normal pattern of fetal movements and c) alarm women when this pattern changes. Care professionals should emphasize that counting of fetal movements is not related only to movements’ quantity (number) but also to movements’ quality (density).
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Akselsson A, Lindgren H, Georgsson S, Warland J, Pettersson K, Rådestad I. Daily structured approach to awareness of fetal movements and pregnancy outcome - a prospective study. SEXUAL & REPRODUCTIVE HEALTHCARE 2019; 20:32-37. [PMID: 31084815 DOI: 10.1016/j.srhc.2019.02.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 01/07/2019] [Accepted: 02/11/2019] [Indexed: 10/27/2022]
Abstract
OBJECTIVES We investigated how women, seeking care due to decreased movements, had paid attention to fetal movements and if the method of monitoring was associated with pregnancy outcome. METHODS A questionnaire was distributed to women from gestational week 28, who had sought care due to decreased fetal movements in Stockholm between January 1st and December 31st, 2014. Women were included in the study if the examination did not reveal any signs of a compromised fetus requiring immediate intervention. Birth outcome and sociodemographic data were collected from the obstetric record register. RESULTS There were 29166 births in Stockholm in 2014, we have information from 2683 women who sought care for decreased fetal movements. The majority (96.6%) of the women stated that they paid attention to fetal movements. Some women observed fetal movements weekly (17.2%) and 69.5% concentrated on fetal movements daily (non-structured group). One in ten (9.9%) used counting methods daily for observing fetal movements (structured group). Women in the structured group more often had caesarean section before onset of labor (RR 1.6, 95% CI 1.2-2.2) and a lower risk of their baby being transferred to neonatal nursery (RR 0.25, 95% CI 0.03-0.94) compared to women in the non-structured group. CONCLUSIONS Women, who had a daily and structured approach to awareness of fetal movements, were more likely to have a caesarean section but their babies were less likely to be transferred to a neonatal nursery as compared with women who used a non-structured method daily.
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Affiliation(s)
- Anna Akselsson
- Sophiahemmet University and Department of Women and Childreńs Health, Karolinska Institutet, Stockholm, Sweden.
| | - Helena Lindgren
- Department of Women and Childreńs Health, Karolinska Institutet, Stockholm, Sweden.
| | - Susanne Georgsson
- Sophiahemmet University and Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.
| | - Jane Warland
- School of Nursing and Midwifery, University of South Australia, Adelaide, Australia.
| | - Karin Pettersson
- Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.
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Bradford BF, Thompson JMD, Heazell AEP, Mccowan LME, McKinlay CJD. Understanding the associations and significance of fetal movements in overweight or obese pregnant women: a systematic review. Acta Obstet Gynecol Scand 2017; 97:13-24. [PMID: 29068467 DOI: 10.1111/aogs.13250] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 10/18/2017] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Presentation with decreased fetal movement (DFM) is associated with fetal growth restriction and stillbirth. Some studies report that DFM is frequent among overweight or obese mothers. We aimed to determine the significance and associations of fetal movements in women of increased body size. MATERIAL AND METHODS This systematic review was conducted in accordance with the PRISMA statement and the protocol was registered with PROSPERO (CRD42016046352). Major databases were explored from inception to September 2017, using a predefined search strategy. We restricted inclusion to studies published in English and considered studies of any design that compared fetal movements in women of increased and normal body size. Two authors independently extracted data and assessed quality. RESULTS We included 23 publications from 19 observational studies; data were extracted from 10 studies. Increased maternal body size was not associated with altered perception of fetal movement (four studies, 95 women, very low-quality evidence), but was associated with increased presentation for DFM (two cohort studies, 20 588 women, OR 1.56, 95% CI 1.27-1.92: three case-control studies, 3445 women, OR 1.32, 95% CI 1.12-1.54; low-quality evidence). Among women with DFM, increased maternal body size was associated with increased risk of stillbirth and fetal growth restriction (one study, 2168 women, very low-quality evidence). CONCLUSIONS This systematic review identified limited evidence that women with increased body size are more likely to present with DFM but do not have impaired perception of fetal movements. In women with DFM, increased body size is associated with worse pregnancy outcome, including stillbirth.
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Affiliation(s)
- Billie F Bradford
- Department of Obstetrics and Gynecology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - John M D Thompson
- Department of Obstetrics and Gynecology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.,Department of Pediatrics: Child and Youth Health, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Alexander E P Heazell
- Maternal and Fetal Health Research Center, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.,Manchester Academic Health Science Center, St Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Lesley M E Mccowan
- Department of Obstetrics and Gynecology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Chris J D McKinlay
- Department of Pediatrics: Child and Youth Health, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.,Liggins Institute, University of Auckland, Auckland, New Zealand.,Kidz First Neonatal Care, Counties Manukau Health, Auckland, New Zealand
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5
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A nuanced picture of illicit drug use in 17 Italian cities through functional principal component analysis of temporal wastewater data. J Public Health (Oxf) 2016. [DOI: 10.1007/s10389-016-0717-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Aviram A, Shmueli A, Hiersch L, Ashwal E, Wiznitzer A, Yogev Y, Hadar E. Pregnancy Outcome in Women with Decreased Sensation of Fetal Movements at Term According to Parity. Birth 2016; 43:42-8. [PMID: 26643600 DOI: 10.1111/birt.12205] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/23/2015] [Indexed: 12/30/2022]
Abstract
BACKGROUND Decreased sensation of fetal movements (DFM) is a common maternal complaint. Thus, we aimed to evaluate the association between DFM and pregnancy outcome in singleton gestation at term according to parity. METHODS A retrospective cohort study of singleton pregnancies at term between 2008 and 2013. Eligibility was limited to women carrying a fetus with no known structural or chromosomal anomalies, at 37+0/7 to 42+0/7 weeks of gestation. Women presenting to the delivery ward with DFM were compared with women without similar complaints. RESULTS Overall, 12,564 nulliparous women and 25,292 multiparous women gave birth during the study period; of them, 300 nulliparous women (2.4%) and 525 multiparous women (2.1%) complained of DFM. For nulliparous women, after adjusting for potential confounders, DFM was associated with antepartum fetal death (aOR 4.6 [95% CI 1.1-19.8]), cesarean delivery (CD) (aOR 1.3 [95% CI 1.01-1.8]), 1-minute Apgar score less than 7 (aOR 2.3 [95% CI 1.5-3.5]) and neonatal seizures (aOR 3.2 [95% CI 1.3-8.2]). For multiparous women, DFM was associated with unscheduled CD (aOR 2.7 [95% CI 1.6-4.6]) and CD indicated by intermediate/abnormal fetal heart rate tracing (aOR 4.8 [95% CI 2.8-8.4]). CONCLUSIONS DFM carries different outcomes according to parity. Although for nulliparous women, DFM is associated with increased risk of CD and immediate adverse perinatal outcome, for multiparous women it is associated with increased risk for CD, with no immediate increased risk for adverse perinatal outcome.
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Affiliation(s)
- Amir Aviram
- Helen Schneider Hospital for Women, Rabin Medical Center, Petah Tikva, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Ramat-Aviv, Israel
| | - Anat Shmueli
- Helen Schneider Hospital for Women, Rabin Medical Center, Petah Tikva, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Ramat-Aviv, Israel
| | - Liran Hiersch
- Helen Schneider Hospital for Women, Rabin Medical Center, Petah Tikva, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Ramat-Aviv, Israel
| | - Eran Ashwal
- Helen Schneider Hospital for Women, Rabin Medical Center, Petah Tikva, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Ramat-Aviv, Israel
| | - Arnon Wiznitzer
- Helen Schneider Hospital for Women, Rabin Medical Center, Petah Tikva, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Ramat-Aviv, Israel
| | - Yariv Yogev
- Helen Schneider Hospital for Women, Rabin Medical Center, Petah Tikva, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Ramat-Aviv, Israel
| | - Eran Hadar
- Helen Schneider Hospital for Women, Rabin Medical Center, Petah Tikva, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Ramat-Aviv, Israel
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Winje BA, Wojcieszek AM, Gonzalez-Angulo LY, Teoh Z, Norman J, Frøen JF, Flenady V. Interventions to enhance maternal awareness of decreased fetal movement: a systematic review. BJOG 2015; 123:886-98. [DOI: 10.1111/1471-0528.13802] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/11/2015] [Indexed: 11/28/2022]
Affiliation(s)
- BA Winje
- Division of Infectious Disease Control; Norwegian Institute of Public Health; Oslo Norway
| | - AM Wojcieszek
- Mater Research Institute; The University of Queensland; Brisbane Qld Australia
| | - LY Gonzalez-Angulo
- Division of Infectious Disease Control; Norwegian Institute of Public Health; Oslo Norway
| | - Z Teoh
- Mater Research Institute; The University of Queensland; Brisbane Qld Australia
| | - J Norman
- Tommy's Centre for Maternal and Fetal Health; Queen's Medical Research Institute; University of Edinburgh MRC Centre for Reproductive Health; Edinburgh Scotland
| | - JF Frøen
- Department of International Public Health; Norwegian Institute of Public Health; Oslo Norway
| | - V Flenady
- Mater Research Institute; The University of Queensland; Brisbane Qld Australia
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Salvatore S, Bramness JG, Reid MJ, Thomas KV, Harman C, Røislien J. Wastewater-Based Epidemiology of Stimulant Drugs: Functional Data Analysis Compared to Traditional Statistical Methods. PLoS One 2015; 10:e0138669. [PMID: 26394227 PMCID: PMC4578919 DOI: 10.1371/journal.pone.0138669] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 09/02/2015] [Indexed: 12/03/2022] Open
Abstract
Background Wastewater-based epidemiology (WBE) is a new methodology for estimating the drug load in a population. Simple summary statistics and specification tests have typically been used to analyze WBE data, comparing differences between weekday and weekend loads. Such standard statistical methods may, however, overlook important nuanced information in the data. In this study, we apply functional data analysis (FDA) to WBE data and compare the results to those obtained from more traditional summary measures. Methods We analysed temporal WBE data from 42 European cities, using sewage samples collected daily for one week in March 2013. For each city, the main temporal features of two selected drugs were extracted using functional principal component (FPC) analysis, along with simpler measures such as the area under the curve (AUC). The individual cities’ scores on each of the temporal FPCs were then used as outcome variables in multiple linear regression analysis with various city and country characteristics as predictors. The results were compared to those of functional analysis of variance (FANOVA). Results The three first FPCs explained more than 99% of the temporal variation. The first component (FPC1) represented the level of the drug load, while the second and third temporal components represented the level and the timing of a weekend peak. AUC was highly correlated with FPC1, but other temporal characteristic were not captured by the simple summary measures. FANOVA was less flexible than the FPCA-based regression, and even showed concordance results. Geographical location was the main predictor for the general level of the drug load. Conclusion FDA of WBE data extracts more detailed information about drug load patterns during the week which are not identified by more traditional statistical methods. Results also suggest that regression based on FPC results is a valuable addition to FANOVA for estimating associations between temporal patterns and covariate information.
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Affiliation(s)
- Stefania Salvatore
- Norwegian Centre for Addiction Research, University of Oslo, Oslo, Norway
- * E-mail:
| | | | | | | | | | - Jo Røislien
- Norwegian Centre for Addiction Research, University of Oslo, Oslo, Norway
- Department of Biostatistics, Institute of Basic Medical Sciences, Oslo, Norway
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Bradford B, Maude R. Fetal response to maternal hunger and satiation - novel finding from a qualitative descriptive study of maternal perception of fetal movements. BMC Pregnancy Childbirth 2014; 14:288. [PMID: 25154868 PMCID: PMC4152596 DOI: 10.1186/1471-2393-14-288] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 08/17/2014] [Indexed: 12/20/2022] Open
Abstract
Background Maternal perception of decreased fetal movements is a specific indicator of fetal compromise, notably in the context of poor fetal growth. There is currently no agreed numerical definition of decreased fetal movements, with the subjective perception of a decrease on the part of the mother being the most significant definition clinically. Both qualitative and quantitative aspects of fetal activity may be important in identifying the compromised fetus. Yet, how pregnant women perceive and describe fetal activity is under-investigated by qualitative means. The aim of this study was to explore normal fetal activity, through first-hand descriptive accounts by pregnant women. Methods Using qualitative descriptive methodology, interviews were conducted with 19 low-risk women experiencing their first pregnancy, at two timepoints in their third trimester. Interview transcripts were later analysed using qualitative content analysis and patterns of fetal activity identified were then considered along-side the characteristics of the women and their birth outcomes. Results This paper focuses on a novel finding; the description by pregnant women of fetal behaviour indicative of hunger and satiation. Full findings will be presented in later papers. Most participants (74% 14 of 19) indicated mealtimes were a time of increased fetal activity. Eight participants provided detailed descriptions of increased activity around meals, with seven (37% 7 of 19) of these specifying increased fetal activity prior to meals or in the context of their own hunger. These movements were interpreted as a fetal demand for food often prompting the mother to eat. Interestingly, the women who described increased fetal activity in the context of hunger subsequently gave birth to smaller infants (mean difference 364 gm) than those who did not describe a fetal response to hunger. Conclusions Food seeking behaviour may have a pre-birth origin. Maternal-fetal interaction around mealtimes could constitute an endocrine mediated communication, in the interests of maintaining optimal intrauterine conditions. Further research is warranted to explore this phenomenon and the potential influence of feeding on the temporal organisation of fetal activity in relation to growth.
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Affiliation(s)
- Billie Bradford
- Graduate School of Nursing, Midwifery and Health, Victoria University of Wellington, P O Box 7625, 6242, Newtown Wellington, New Zealand.
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Winje BA, Røislien J, Saastad E, Eide J, Riley CF, Stray-Pedersen B, Frøen JF. Wavelet principal component analysis of fetal movement counting data preceding hospital examinations due to decreased fetal movement: a prospective cohort study. BMC Pregnancy Childbirth 2013; 13:172. [PMID: 24007565 PMCID: PMC3844562 DOI: 10.1186/1471-2393-13-172] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 08/29/2013] [Indexed: 11/23/2022] Open
Abstract
Background Fetal movement (FM) counting is a simple and widely used method of assessing fetal well-being. However, little is known about what women perceive as decreased fetal movement (DFM) and how maternally perceived DFM is reflected in FM charts. Methods We analyzed FM counting data from 148 DFM events occurring in 137 pregnancies. The women counted FM daily from pregnancy week 24 until birth using a modified count-to-ten procedure. Common temporal patterns for the two weeks preceding hospital examination due to DFM were extracted from the FM charts using wavelet principal component analysis; a statistical methodology particularly developed for modeling temporal data with sudden changes, i.e. spikes that are frequently found in FM data. The association of the extracted temporal patterns with fetal complications was assessed by including the individuals’ scores on the wavelet principal components as explanatory variables in multivariable logistic regression analyses for two outcome measures: (i) complications identified during DFM-related consultations (n = 148) and (ii) fetal compromise at the time of consultation (including relevant information about birth outcome and placental pathology). The latter outcome variable was restricted to the DFM events occurring within 21 days before birth (n = 76). Results Analyzing the 148 and 76 DFM events, the first three main temporal FM counting patterns explained 87.2% and 87.4%, respectively, of all temporal variation in the FM charts. These three temporal patterns represented overall counting times, sudden spikes around the time of DFM events, and an inverted U-shaped pattern, explaining 75.3%, 8.6%, and 3.3% and 72.5%, 9.6%, and 5.3% of variation in the total cohort and subsample, respectively. Neither of the temporal patterns was significantly associated with the two outcome measures. Conclusions Acknowledging that sudden, large changes in fetal activity may be underreported in FM charts, our study showed that the temporal FM counting patterns in the two weeks preceding DFM-related consultation contributed little to identify clinically important changes in perceived FM. It thus provides insufficient information for giving detailed advice to women on when to contact health care providers. The importance of qualitative features of maternally perceived DFM should be further explored.
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Affiliation(s)
- Brita Askeland Winje
- Division of Epidemiology, Norwegian Institute of Public Health, PO Box 4404, Nydalen, 0403, Oslo, Norway.
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Røislien J, Winje B. Feature extraction across individual time series observations with spikes using wavelet principal component analysis. Stat Med 2013; 32:3660-9. [PMID: 23553851 DOI: 10.1002/sim.5797] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Revised: 01/15/2013] [Accepted: 02/26/2013] [Indexed: 11/08/2022]
Abstract
Clinical studies frequently include repeated measurements of individuals, often for long periods. We present a methodology for extracting common temporal features across a set of individual time series observations. In particular, the methodology explores extreme observations within the time series, such as spikes, as a possible common temporal phenomenon. Wavelet basis functions are attractive in this sense, as they are localized in both time and frequency domains simultaneously, allowing for localized feature extraction from a time-varying signal. We apply wavelet basis function decomposition of individual time series, with corresponding wavelet shrinkage to remove noise. We then extract common temporal features using linear principal component analysis on the wavelet coefficients, before inverse transformation back to the time domain for clinical interpretation. We demonstrate the methodology on a subset of a large fetal activity study aiming to identify temporal patterns in fetal movement (FM) count data in order to explore formal FM counting as a screening tool for identifying fetal compromise and thus preventing adverse birth outcomes.
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Affiliation(s)
- Jo Røislien
- Division of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway
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