Imperial College London

Dr Sana Usman

Faculty of MedicineDepartment of Metabolism, Digestion and Reproduction

Honorary Research Associate
 
 
 
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s.usman

 
 
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Commonwealth BuildingHammersmith Campus

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Publications

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33 results found

Dall'Asta A, Girardelli S, Usman S, Lawin-O'Brien A, Paramasivam G, Frusca T, Lees CCet al., 2020, Etiology and perinatal outcome in periviable fetal growth restriction associated with structural or genetic anomalies, Ultrasound in Obstetrics and Gynecology, Vol: 55, Pages: 368-374, ISSN: 0960-7692

OBJECTIVE: To investigate the aetiology and the perinatal outcome of fetuses diagnosed with periviable fetal growth restriction (FGR) associated with structural defects or genetic anomalies. METHODS: Retrospective study conducted at a referral Fetal Medicine unit. Singleton pregnancies seen between 2005 and 2018 in which FGR, defined by fetal abdominal circumference ≤3rd percentile for the gestational age, was diagnosed between 22+0 -25+6 weeks of gestation were enrolled. The study group included periviable FGR associated with genetic or structural anomalies ("anomalous FGR"), while the control group consisted in structurally and genetically normal FGR ("non-anomalous FGR"). The results of the genetic tests, of the TORCH screening and of the post-mortem examination as well as the perinatal outcomes were investigated. RESULTS: Of 255 cases, 188 fetuses were eligible, of whom 52 (28%) were anomalous FGR and 136 (72%) non-anomalous FGR. Confirmed genetic abnormalities accounted for 17/52 cases (33%) of anomalous FGR, with trisomy 18 constituting over 50% (9/17, 53%). The most common structural defects associated with FGR were CNS abnormalities (13/35, 37%). Overall, 12 cases survived the neonatal period. No differences were found in terms of perinatal survival between anomalous and non-anomalous FGR. CONCLUSIONS: Of anomalous FGR, most are associated with structural defects. The association of structural abnormality with a genetic defect and FGR at periviable gestation was invariably lethal, while the combination of periviable FGR and structural defect in the absence of a confirmed genetic abnormality was associated with survival into infancy in four out of five cases, with an overall chance of perinatal survival of one in three. These data can be used for the counselling of the prospective parents. This article is protected by copyright. All rights reserved.

Journal article

Kahrs BH, Usman S, Ghi T, Youssef A, Torkildsen EA, Lindtjørn E, Østborg TB, Benediktsdottir S, Brooks L, Harmsen L, Salvesen KÅ, Lees CC, Eggebø TMet al., 2019, Descent of fetal head during active pushing: secondary analysis of prospective cohort study investigating ultrasound examination before operative vaginal delivery, Ultrasound in Obstetrics and Gynecology, Vol: 54, Pages: 524-529, ISSN: 0960-7692

OBJECTIVES: To investigate if descent of the fetal head during active pushing was associated with duration of operative vaginal delivery, delivery mode and neonatal outcome in nulliparous women with prolonged second stage of labor. METHODS: We conducted a prospective cohort study between November 2013 and July 2016 in five European countries. Fetal head descent was measured with transperineal ultrasound. Head-perineum distance (HPD) was measured between contractions and at maximum contraction during active pushing, and the difference was calculated as delta-HPD. The main outcome was duration of operative vaginal delivery estimated with survival analyses as hazard rations (HRs) for a vaginal delivery, and values >1 show shorter duration. We differentiated delta-HPD into quartiles and compared delivery mode and neonatal outcome between groups. RESULTS: The study population comprised 204 women. Duration of vacuum extraction was shorter with increasing delta-HPD. Estimated mean duration was 10.0, 9.0, 8.8 and 7.5 minutes in quartile 1-4, and the adjusted hazard ratio for vaginal delivery using increasing delta-HPD as continuous variable was 1.04 (95% CI 1.01-1.08). Mean delta-HPD was 7 mm (-10 to 37). Delta-HPD was either negative or ≤2 mm in the lowest quartile. Overall, 7/50 (14%) were delivered with cesarean section in this group compared to 8/154 (5%) if delta-HPD was >2 mm (p <0.05). There was no significant association between umbilical artery pH or Apgar score <7 and delta-HPD groups. CONCLUSION: Lack of fetal head descent during active pushing was associated with longer duration of operative vaginal delivery and higher frequency of cesarean section.

Journal article

Usman S, Kahrs BH, Wilhelm-Benartzi C, Hassan WA, Barton H, Salvesen KA, Eggebø TM, Lees Cet al., 2019, Prediction of mode of delivery using the first ultrasound-based “intrapartum app”, American Journal of Obstetrics and Gynecology, Vol: 221, Pages: 163-166, ISSN: 0002-9378

Journal article

Wilkinson M, Usman S, Barton H, Lees CCet al., 2019, The views of pregnant women, midwives, and a women's panel on intrapartum ultrasound research: A pilot study, Australasian Journal of Ultrasound in Medicine, Vol: 22, Pages: 186-190, ISSN: 1836-6864

BackgroundUltrasound is increasingly used in labour; however, little data exist on attitudes to its use. We sought to analyse and compare the views of pregnant women, midwives, and a women's panel on the value and use of ultrasound in labour.MethodsFocus groups involving a short presentation on ultrasound, questionnaire, and a question and answer session were held with groups of pregnant women, midwives at 2 inner‐city maternity units, and a RCOG online Women's Panel. Data were collected on attitudes to vaginal examination, ultrasound, predicting Caesarean section, and the utility of a digital representation of labour.ResultsTwenty one midwives and 29 service users (19 pregnant women and 10 women's panel members) participated. Significantly more service users saw positive value in intrapartum ultrasound (P = 0.0005) and predicting Caesarean section (P = 0.03) than midwives. The majority of both groups – 72% (20/29) and 62% (13/21), respectively – thought women would want a digital representation of their labour, with the most popular format being on a mobile phone (56%, 20/36).ConclusionsService users were most and midwives least positive about ultrasound versus vaginal examination, indicating divergence between midwives' perspective of women's need to understand risk and desire to know about their labour. Women found the non‐intrusive nature and accuracy of ultrasound valuable while midwives were concerned about de‐skilling and medicalisation of birth. All groups felt a graphical representation of labour on a device would be helpful.

Journal article

Usman S, Barton H, Wilhelm-Benartzi C, Lees CCet al., 2019, Ultrasound is better tolerated than vaginal examination in and before labour, Australian and New Zealand Journal of Obstetrics and Gynaecology, Vol: 59, Pages: 362-366, ISSN: 0004-8666

BACKGROUND: Intrapartum ultrasound has been proposed as a method of assessing labour progress but its acceptability has not been comprehensively assessed. AIMS: We evaluated the acceptability of intrapartum ultrasound in women having vaginal examination (VE) and ultrasound (US) assessment (transabdominal (TA) and transperineal (TP)) prior to delivery, with and without regional analgesia (RA). MATERIALS AND METHODS: Women at 24-42 weeks gestation were included in a prospective observational cohort study. The acceptability of digital VE and TP US were assessed pre- and post-examination using the modified validated Wijma Delivery Experience Questionnaire. Acceptability scores ranged 6-36 (6 being most and 36 being least positive) in six domains: positive-trust and relax, negative-harmful to baby, worrying, painful, intrusive. RESULTS: Of 119 women recruited, 104 completed both pre- and post-assessment questionnaires. Eighty-nine per cent of women were nulliparous with median gestation 40 + 2 weeks (25-42+1 ). Thirty-two per cent had RA before assessment, 91% in total. The combined acceptability scores of both negative and positive experiences (6 = most acceptable, 36 = least acceptable) for VE and US pre-assessment were 15 and 7 respectively (P < 0.0001: Mann-Whitney U-test). VE was associated with less positive / more negative domain scoring post-assessment 12 and 6, respectively (P < 0.0001). Although RA made no difference to the perceived experience pre-VE (P = 0.9), post-VE, women with RAs considered VEs more acceptable than those without RA (P = 0.0022). CONCLUSION(S): This is the first study to comprehensively assess the acceptability of VE and intrapartum US. US assessment prior to delivery is more acceptable than VE. RA ameliorated the negative experience of the VE post-assessment.

Journal article

Usman S, Kahrs B, Barton H, Salvesen K, Moe Eggebo T, Lees Cet al., 2019, Time to delivery based on sonographic assessment prior to forceps and vacuum, Australasian Journal of Ultrasound in Medicine, Vol: 22, Pages: 111-117, ISSN: 1836-6864

IntroductionTo compare the duration of vacuum and forceps delivery in relation to ultrasound assessment of fetal head position and station.MethodsA prospective single‐centre cohort study in nulliparous women at term with prolonged second stage of labour. Fetal head position was determined using transabdominal ultrasound and station as head‐perineum distance (HPD) from transperineal ultrasound prior to an instrument. The primary outcome was duration of vacuum and forceps to vaginal delivery and was analysed as survival expressed by hazard ratio (HR). Secondary outcomes were delivery mode and immediate neonatal outcome.ResultsIn the study population of 54 women, the primary instrument was vacuum for 36 and forceps for 18. Four women were delivered by Caesarean section. Estimated median duration for forceps deliveries was 5 min (95% CI 4.0–6.0) vs. 9 min (95% CI 7.3–10.6) for vacuum deliveries (P = 0.17; Log‐rank test). The HR for vaginal delivery was 2.02 (95% CI 1.04–3.91, P = 0.038) after adjusting for HPD, maternal age and BMI. OP position had minor influence on the primary outcome (HR changed from 2.02 to 2.08). The first instrument failed in 11/31 (35.5%) where HPD > 35 mm vs. 2/21 (9.5%) where HPD ≤ 35 mm (P < 0.05). There were no cases of Apgar score <7 at 5 min or umbilical artery pH < 7.1.ConclusionIn prolonged second stage, delivery with forceps was achieved more quickly than by vacuum when matched for ultrasound determined head station. Irrespective of which was the primary instrument, the failure rate was greater at higher head stations.

Journal article

Dall'Asta A, Girardelli S, Usman S, Lawin-O'Brien A, Lees Cet al., 2019, EP.137 Aetiology and short term outcome in periviable fetal growth restriction associated with structural and chromosomal abnormalities, British Maternal & Fetal Medicine Society (BMFMS) 21st Annual Conference 2019., Publisher: Wiley, Pages: 65-65, ISSN: 1470-0328

Conference paper

Lees C, Usman S, 2018, Response to: Vaginal examination and fear of childbirth, AUSTRALIAN & NEW ZEALAND JOURNAL OF OBSTETRICS & GYNAECOLOGY, Vol: 58, Pages: E25-E25, ISSN: 0004-8666

Journal article

Nijjar S, Usman S, Tay J, Akmal Set al., 2018, Rotational deliveries: how can we manage them better?, Publisher: WILEY, Pages: 57-57, ISSN: 1470-0328

Conference paper

Usman S, Kahrs B, Barton H, Eggebo TM, Lees Cet al., 2018, OP17.04 Using the intrapartum app on a new population, ISUOG World Congress 2018, Publisher: Wiley, Pages: 116-116, ISSN: 1469-0705

Conference paper

Usman S, Lees C, Khars BH, Barton H, Salvesen KA, Eggebø TMet al., 2018, P06.07: Time to delivery based on sonographic assessment prior to forceps and vacuum: a pilot study, ISUOG World Congress 2018, Publisher: Wiley, Pages: 157-157, ISSN: 0960-7692

Conference paper

Usman S, Van Calster B, Barton H, Lees Cet al., 2018, P06.08 Prediction of emergency caesarean sections; which variables are important, ISUOG World Congress 2018, Publisher: Wiley, Pages: 157-157, ISSN: 1469-0705

Conference paper

Usman S, Barton H, Van Calster B, Lees Cet al., 2018, P06.10 Prediction of emergency caesarean sections; does umbilical cerebral ratio have an important role to play?, ISUOG World Congress 2018, Publisher: Wiley, Pages: 158-158, ISSN: 1469-0705

Conference paper

Wilkinson M, Usman S, Barton H, Alojado M, Lees Cet al., 2018, OP17.03: The views of pregnant women, midwives and a women's panel on intrapartum ultrasound research: a pilot study, ISUOG World Congress 2018, Publisher: Wiley, Pages: 116-116, ISSN: 1469-0705

Conference paper

Kahrs BH, Usman S, Ghi T, Youssef A, Torkildsen EA, Lindtjørn E, Østborg TB, Benediktsdottir S, Brooks L, Harmsen L, Salvesen KÅ, Lees CC, Eggebø TMet al., 2018, Fetal rotation during vacuum extractions for prolonged labor: a prospective cohort study, Acta Obstet Gynecol Scand, Vol: 97, Pages: 998-1005

INTRODUCTION: The aim of the study was to investigate fetal head rotation during vacuum extraction. MATERIAL AND METHODS: We conducted a prospective cohort study from November 2013 to July 2016 in seven European hospitals. Fetal head position was determined with transabdominal or transperineal ultrasound and categorized as occiput anterior (OA), occiput transverse (OT) or occiput posterior (OP) position. Main outcome was the proportion of fetuses rotating during vacuum extraction. Secondary outcomes were conversion of delivery method, duration of vacuum extraction, umbilical artery pH <7.10 and agreement between clinical and ultrasound assessments. RESULTS: The study population comprised 165 women. During vacuum extraction 117/119 (98%) remained in OA and two fetuses rotated to OP position. Rotation from OT to OA position occurred in 14/19 (74%) and to OP position in 5/19 (26%). Rotation from OP to OA position occurred in 15/25 (60%), and 10/25 (40%) fetuses remained in OP position. Delivery information was missing in two cases. The conversion rate from vacuum extraction to cesarean section or forceps was 10% in the OA group vs. 23% in the non-OA group; p < 0.05. The estimated duration of vacuum extraction was significantly shorter in OA fetuses, 7 min vs. 10 min (log rank test p < 0.01). There was no significant difference in umbilical artery pH < 7.10 between OA and non-OA position. Cohens Kappa of agreement between clinical and ultrasound assessments was 0.42 (95% CI 0.26-0.57). CONCLUSION: Most fetuses in OP or OT positions rotated to OA position during vacuum extraction, but the proportion of failed vacuum extractions remained high.

Journal article

Usman S, Wilkinson M, Barton H, Lees CCet al., 2018, The feasibility and accuracy of ultrasound assessment in the labor room, Journal of Maternal-Fetal and Neonatal Medicine, Vol: 32, Pages: 3442-3451, ISSN: 1476-4954

OBJECTIVE: Vaginal examination is widely used to assess the progress of labor; however, it is subjective and poorly reproducible. We aim to assess the feasibility and accuracy of transabdominal and transperineal ultrasound compared to vaginal examination in the assessment of labor and its progress. METHODS: Women were recruited as they presented for assessment of labor to a tertiary inner city maternity service. Paired vaginal and ultrasound assessments were performed in 192 women at 24-42 weeks. Fetal head position was assessed by transabdominal ultrasound defined in relation to the occiput position transformed to a 12-hour clock face; fetal head station defined as head-perineum distance by transperineal ultrasound; cervical dilatation by anterior to posterior cervical rim measurement and caput succedaneum by skin-skull distance on transperineal ultrasound. RESULTS: Fetal head position was recorded in 99.7% (298/299) of US and 51.5% (154/299) on vaginal examination (p < .0001 1 ). Bland-Altman analysis showed 95% limits of agreement, -5.31 to 4.84 clock hours. Head station was recorded in 96.3% (308/320) on vaginal examination (VE) and 95.9% (307/320) on US (p = .79 1 ). Head station and head perineum distance were negatively correlated (Spearman's r = -.57, p < .0001). 54.4% (178/327) of cervical dilatation measurements were determined using US and 100% on VE/speculum (p < .0001). Bland-Altman analysis showed 95% limits of agreement -2.51-2.16 cm. The presence of caput could be assessed in 98.4% (315/320) of US and was commented in 95.3% (305/320) of VEs, with agreement for the presence of caput of 76% (p < .05). Fetuses with caput greater than 10 mm had significantly lower head station (p < .0001). CONCLUSIONS: We describe comprehensive ultrasound assessments in the labor room that could be translated to the assessment of women in labor.

Journal article

Usman S, Wilkinson M, Barton H, Lees Cet al., 2017, OP19.10 Transperineal ultrasound to assess fetal head station in labour: a more objective assessment of labour?, ISUOG World Congress 2017, Publisher: Wiley, Pages: 112-112, ISSN: 0960-7692

Conference paper

Wilkinson M, Usman S, Barton H, Lees Cet al., 2017, OP19.07 Transabdominal ultrasound to assess fetal position in labour: a gold standard?, ISUOG World Congress 2017, Publisher: Wiley, Pages: 111-111, ISSN: 0960-7692

Conference paper

Usman S, Barton H, Wilhelm-Benartzi C, Lees Cet al., 2017, P13.07 Acceptability of trasabdominal and transperineal ultrasound compared to vaginal examinations prior to delivery, ISUOG World Congress 2017, Publisher: Wiley, Pages: 196-196, ISSN: 0960-7692

Conference paper

Wilkinson M, Usman S, Barton H, Lees Cet al., 2017, EP 19.07 Transperineal ultrasound to assess caput succedaneum in labour: a more objective assessment compared to digital vaginal examinations?, ISUOG World Congress 2017, Publisher: Wiley, Pages: 349-349, ISSN: 0960-7692

Conference paper

Usman S, Lees C, 2017, P04.03 What is the relationship between the cerebro-umbilical ratio, operative delivery for fetal distress and time to delivery in nulliparous women?, ISUOG World Congress 2017, Publisher: Wiley, Pages: 162-163, ISSN: 0960-7692

Conference paper

Usman S, Foo L, Tay J, Bennett PR, Lees Cet al., 2017, Authors' reply [Use of magnesium sulfate in preterm deliveries for neuroprotection of the neonate], Obstetrician and Gynaecologist, Vol: 19, Pages: 255-256, ISSN: 1744-4667

Journal article

Kahrs BH, Usman S, Ghi T, Youssef A, Torkildsen EA, Lindtjorn E, Ostborg TB, Benediktsdottir S, Brooks L, Harmsen L, Romundstad PR, Salvesen KA, Lees CC, Eggebo TMet al., 2017, Sonographic prediction of outcome of vacuum deliveries: a multicenter, prospective cohort study, American Journal of Obstetrics and Gynecology, Vol: 217, ISSN: 0002-9378

BackgroundSafe management of the second stage of labor is of great importance. Unnecessary interventions should be avoided and correct timing of interventions should be focused. Ultrasound assessment of fetal position and station has a potential to improve the precision in diagnosing and managing prolonged or arrested labors. The decision to perform vacuum delivery is traditionally based on subjective assessment by digital vaginal examination and clinical expertise and there is currently no method of objectively quantifying the likelihood of successful delivery. Prolonged attempts at vacuum delivery are associated with neonatal morbidity and maternal trauma, especially so if the procedure is unsuccessful and a cesarean is performed.ObjectiveThe aim of the study was to assess if ultrasound measurements of fetal position and station can predict duration of vacuum extractions, mode of delivery, and fetal outcome in nulliparous women with prolonged second stage of labor.Study DesignWe performed a prospective cohort study in nulliparous women at term with prolonged second stage of labor in 7 European maternity units from 2013 through 2016. Fetal head position and station were determined using transabdominal and transperineal ultrasound, respectively. Our preliminary clinical experience assessing head-perineum distance prior to vacuum delivery suggested that we should set 25 mm for the power calculation, a level corresponding roughly to +2 below the ischial spines. The main outcome was duration of vacuum extraction in relation to ultrasound measured head-perineum distance with a predefined cut-off of 25 mm, and 220 women were needed to discriminate between groups using a hazard ratio of 1.5 with 80% power and alpha 5%. Secondary outcomes were delivery mode and umbilical artery cord blood samples after birth. The time interval was evaluated using survival analyses, and the outcomes of delivery were evaluated using receiver operating characteristic curves and descriptive st

Journal article

Usman S, Barton H, Wilhelm-Benartzi C, Hirst C, Lees CCet al., 2017, Acceptability of transabdominal and transperineal ultrasound compared to vaginal examinations prior to delivery, Publisher: WILEY, Pages: 8-8, ISSN: 1470-0328

Conference paper

Usman S, Foo L, Tay J, Bennett PR, Lees Cet al., 2017, Use of magnesium sulfate in preterm deliveries for neuroprotection of the neonate, Obstetrician and Gynaecologist, Vol: 19, Pages: 21-28, ISSN: 1744-4667

Key content The prevalence of preterm birth is increasing and owing to advances in neonatal care, more infants are surviving. However, in parallel with this, the incidence of cerebral palsy (CP) is also rising. Magnesium sulfate (MgSO4) is currently recommended for use in women who are at risk of giving birth at less than 30–32 weeks of gestation for neuroprotection of their infants. The exact mechanism of action remains unclear. Meta‐analyses report encouraging results that are consistent with a modest but tangible benefit for the use of MgSO4, and suggest a number needed to treat (NNT) to prevent one in 46 cases of CP in infants born preterm before 30 weeks of gestation and one in 63 cases of CP in infants born preterm before 34 weeks of gestation.Learning objectives To gain an understanding of the risk of neurodisability in infants delivered preterm. To become familiar with the main studies assessing the use of MgSO4 for neuroprotection in preterm deliveries. To become aware of the relevant international guidelines.Ethical issues Concerns have been raised regarding the higher number of perinatal deaths reported with the use of MgSO4 in the MagNET study. This was not substantiated in the Cochrane review. Given that MgSO4 is a safe, readily available and inexpensive drug, even if there were only to be modest benefits from its use, the risk–benefit ratio is in favour of its use.

Journal article

Usman S, Hirst C, Oliveira M, Wilhelm-Benartzi C, Lees Cet al., 2016, Acceptability of transabdominal and transperineal ultrasound compared to vaginal examinations peri-delivery, BJOG - An International Journal of Obstetrics and Gynaecology, Vol: 123, Pages: 165-166, ISSN: 1470-0328

Journal article

Usman S, Lees C, 2016, The acceptability of intrapartum ultrasound, British Maternal & Fetal Medicine Society (BMFMS) 18th Annual Conference 2016, Publisher: Wiley, Pages: 102-102, ISSN: 1471-0528

Conference paper

Usman S, lees C, 2015, The benefits and pitfalls of intrapartum ultrasound, Australasian Journal of Ultrasound Medicine, ISSN: 1836-6864

Journal article

Eggebo TM, Wilhelm-Benartzi C, Hassan WA, Usman S, Salvesen KA, Lees CCet al., 2015, A model to predict vaginal delivery in nulliparous women based on maternal characteristics and intrapartum ultrasound, AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY, Vol: 213, ISSN: 0002-9378

Journal article

De Rosnay P, Chandiramani M, Usman S, Owen Eet al., 2011, Injury of epigastric vessels at laparoscopy: Diagnosis and management, Gynecological Surgery, Vol: 8, Pages: 353-356, ISSN: 1613-2076

Journal article

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