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1.
Ultrasound Obstet Gynecol ; 63(6): 723-730, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38324675

ABSTRACT

OBJECTIVE: To assess the diagnostic accuracy of ultrasound for detecting placenta accreta spectrum (PAS) during the first trimester of pregnancy and compare it with the accuracy of second- and third-trimester ultrasound examination in pregnancies at risk for PAS. METHODS: PubMed, EMBASE and Web of Science databases were searched to identify relevant studies published from inception until 10 March 2023. Inclusion criteria were cohort, case-control or cross-sectional studies that evaluated the accuracy of ultrasound examination performed at < 14 weeks of gestation (first trimester) or ≥ 14 weeks of gestation (second/third trimester) for the diagnosis of PAS in pregnancies with clinical risk factors. The primary outcome was the diagnostic accuracy of sonography in detecting PAS in the first trimester, compared with the accuracy of ultrasound examination in the second and third trimesters. The secondary outcome was the diagnostic accuracy of each sonographic marker individually across the trimesters of pregnancy. The reference standard was PAS confirmed at pathological or surgical examination. The potential of ultrasound and different ultrasound signs to detect PAS was assessed by computing summary estimates of sensitivity, specificity, diagnostic odds ratio and positive and negative likelihood ratios. RESULTS: A total of 37 studies, including 5764 pregnancies at risk of PAS, with 1348 cases of confirmed PAS, were included in our analysis. The meta-analysis demonstrated that ultrasound had a sensitivity of 86% (95% CI, 78-92%) and specificity of 63% (95% CI, 55-70%) during the first trimester, and a sensitivity of 88% (95% CI, 84-91%) and specificity of 92% (95% CI, 85-96%) during the second/third trimester. Regarding sonographic markers examined in the first trimester, lower uterine hypervascularity exhibited the highest sensitivity (97% (95% CI, 19-100%)), and uterovesical interface irregularity demonstrated the highest specificity (99% (95% CI, 96-100%)). In the second/third trimester, loss of clear zone had the highest sensitivity (80% (95% CI, 72-86%)), and uterovesical interface irregularity exhibited the highest specificity (99% (95% CI, 97-100%)). CONCLUSIONS: First-trimester ultrasound examination has similar accuracy to second- and third-trimester ultrasound examinations for the diagnosis of PAS. Routine first-trimester ultrasound screening for patients at high risk of PAS may improve detection rates and allow earlier referral to tertiary care centers for pregnancy management. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Placenta Accreta , Pregnancy Trimester, First , Sensitivity and Specificity , Ultrasonography, Prenatal , Humans , Female , Pregnancy , Placenta Accreta/diagnostic imaging , Pregnancy Trimester, Third , Pregnancy Trimester, Second , Pregnancy Trimesters
2.
Ultrasound Obstet Gynecol ; 62(6): 860-866, 2023 12.
Article in English | MEDLINE | ID: mdl-37470712

ABSTRACT

OBJECTIVES: To use superb microvascular imaging (SMI) to evaluate longitudinally spiral artery (SA) and uterine artery (UtA) vascular adaptation in normal human pregnancy, and to develop reference ranges for use at various gestational ages throughout pregnancy. METHODS: The data for this study were obtained from the National Institutes of Health (NIH)-funded Human Placenta Project. Women aged 18-35 years, with a body mass index < 30 kg/m2 , without comorbidities, with a singleton gestation conceived spontaneously, and gestational age at or less than 13 + 6 weeks were eligible for inclusion. The current analysis was restricted to uncomplicated pregnancies carried to term. Exclusion criteria included maternal or neonatal complications, fetal or umbilical cord anomalies, abnormal placental implantation or delivery < 37 weeks. Women who fulfilled the inclusion criteria formed the reference population of the Human Placenta Project study. Each participant underwent eight ultrasound examinations during pregnancy. The pulsatility index (PI) of both the left and right UtA were obtained twice for each artery and the presence or absence of a notch was noted. Using SMI technology, the total number of SA imaged was recorded in a sagittal placental section at the level of cord insertion. The PI and peak systolic velocity (PSV) were also measured in a total of six SA, including two in the central portion of the placenta, two peripherally towards the uterine fundal portion, and two peripherally towards the lower uterine segment. RESULTS: A total of 90 women fulfilled the study criteria. Maternal UtA-PI decreased throughout the first half of pregnancy from a mean ± SD of 1.39 ± 0.50 at 12-13 weeks' gestation to 0.88 ± 0.24 at 20-21 weeks' gestation. The mean number of SA visualized in a sagittal plane of the placenta increased from 8.83 ± 2.37 in the first trimester to 16.99 ± 3.31 in the late-third trimester. The mean SA-PI was 0.57 ± 0.12 in the first trimester and decreased progressively during the second trimester, reaching a nadir of 0.40 ± 0.10 at 24-25 weeks, and remaining constant until the end of pregnancy. SA-PSV was highest in early pregnancy with a mean of 57.16 ± 14.84 cm/s at 12-13 weeks' gestation, declined to a mean of 49.38 ± 17.88 cm/s at 20-21 weeks' gestation and continued to trend downward for the remainder of pregnancy, reaching a nadir of 34.50 ± 15.08 cm/s at 36-37 weeks' gestation. A statistically significant correlation was noted between SA-PI and UtA-PI (r = 0.5633; P < 0.001). Multilevel regression models with natural cubic splines were used to create reference ranges of SA-PSV and SA-PI for given gestational ages. CONCLUSION: From early gestation, we have demonstrated the ability to image and quantify SA blood flow in normal pregnancy, and have developed reference ranges for use at various gestational ages throughout pregnancy. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Pre-Eclampsia , Uterine Artery , Infant, Newborn , Pregnancy , Female , Humans , Uterine Artery/diagnostic imaging , Uterine Artery/physiology , Placenta/diagnostic imaging , Placenta/blood supply , Ultrasonography, Prenatal , Ultrasonography , Pregnancy Trimester, Third , Gestational Age , Pulsatile Flow , Pre-Eclampsia/epidemiology
4.
J Matern Fetal Neonatal Med ; 35(20): 3860-3866, 2022 Oct.
Article in English | MEDLINE | ID: mdl-33108930

ABSTRACT

PURPOSE: Postpartum depression (PPD) is a common pregnancy complication. The association between cesarean delivery (CD) and PPD has shown conflicting results in prior studies, although emergent CD appears to be a clear risk factor. Establishing PPD risk is critical and may, however, be related to the unplanned nature of the CD, rather than the surgery itself. Our objective was to determine whether women who underwent unplanned CD were more likely than those with vaginal delivery to have higher depressive symptoms and thus screen positive for PPD risk in the immediate postpartum period. MATERIALS AND METHODS: This cohort study was conducted at a community medical center using data for deliveries between 8/2015-1/2016. Women were screened in the hospital for depressive symptoms (PPD risk) using the Edinburgh Postnatal Depression Scale (EPDS) within 4 days post-delivery. Logistic regression, adjusting for maternal race/ethnicity and parity, was performed to evaluate the association between delivery route (vaginal vs planned vs unplanned CD) and PPD risk (EPDS ≥ 10). RESULTS: A total of 2094 women had complete data for analysis. Overall, 44 women (2.1%) screened positive for PPD risk. Logistic regression results showed that unplanned CD was significantly associated with PPD risk (OR = 2.28, 95% CI 1.13-4.57, p = .022), after adjusting for parity and race/ethnicity. Planned CD was not associated with PPD risk. CONCLUSION: Unplanned CD may be an independent risk factor for PPD risk in the immediate postpartum period. This finding might explain why some previous studies have demonstrated different results with regards to risk of CD where the unplanned nature of the delivery was not accounted for.


Subject(s)
Depression, Postpartum , Cesarean Section/adverse effects , Cohort Studies , Depression/diagnosis , Depression, Postpartum/diagnosis , Depression, Postpartum/epidemiology , Depression, Postpartum/etiology , Female , Humans , Postpartum Period , Pregnancy
5.
Phys Rev Lett ; 110(22): 222003, 2013 May 31.
Article in English | MEDLINE | ID: mdl-23767714

ABSTRACT

We present the first lattice QCD calculation of the decay constants f(B) and f(B(s)) with physical light quark masses. We use configurations generated by the MILC Collaboration including the effect of u, d, s, and c highly improved staggered quarks in the sea at three lattice spacings and with three u/d quark mass values going down to the physical value. We use improved nonrelativistic QCD (NRQCD) for the valence b quarks. Our results are f(B)=0.186(4) GeV, f(B(s))=0.224(4) GeV, f(B(s))/f(B)=1.205(7), and M(B(s))-M(B)=85(2) MeV, superseding earlier results with NRQCD b quarks. We discuss the implications of our results for the standard model rates for B((s))→µ(+)µ(-) and B→τν.

6.
Phys Rev Lett ; 107(11): 112002, 2011 Sep 09.
Article in English | MEDLINE | ID: mdl-22026657

ABSTRACT

We present the first application of the background field method to nonrelativistic QCD (NRQCD) on the lattice in order to determine the one-loop radiative corrections to the coefficients of the NRQCD action in a manifestly gauge-covariant manner. The coefficients of the σ·B term in the NRQCD action and the four-fermion spin-spin interaction are computed at the one-loop level; the resulting shift of the hyperfine splitting of bottomonium is found to bring the lattice predictions in line with experiment.

7.
J Obstet Gynaecol ; 30(6): 578-82, 2010.
Article in English | MEDLINE | ID: mdl-20701506

ABSTRACT

There is currently inconsistent evidence and clinical guidance on how to best manage a pregnancy complicated by reduced fetal movements. This novel, web-based, anonymous questionnaire evaluated 96 assessment and management approaches from doctors working in obstetrics in the Republic of Ireland who were presented with a clinical scenario of a primigravida concerned about reduced fetal movements at 39+3 weeks' gestation. This study identified a lack of clinical practice guidelines available in maternity hospitals in the Republic of Ireland. We demonstrated that almost all clinicians applied more than one assessment method and that most incorporated a cardiotocograph into their assessment. There was a low uptake of simple symphysio-fundal height measurement and high usage of kickcharts. The minority of clinicians admitted or induced their patients. This survey identified the need for national and international guidelines to ensure safe antepartum care and delivery.


Subject(s)
Fetal Monitoring , Fetal Movement , Practice Patterns, Physicians' , Pregnancy Complications , Female , Fetal Monitoring/methods , Fetal Monitoring/standards , Gestational Age , Humans , Ireland , Male , Practice Guidelines as Topic , Pregnancy , Surveys and Questionnaires
8.
Placenta ; 31(10): 893-901, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20708797

ABSTRACT

Being born small for gestational age (SGA) confers significantly increased risks of perinatal morbidity and mortality. Accumulating evidence suggests that an SGA fetus results from a poorly perfused and abnormally developed placenta. Some of the placental features seen in SGA, such as abnormal cell turnover and impaired nutrient transport, can be reproduced by culture of placental explants in hypoxic conditions. Metabolic footprinting offers a hypothesis-generating strategy to investigate factors absorbed by and released from this tissue in vitro. Previously, metabolic footprinting of the conditioned culture media has identified differences in placental explants cultured under normoxic and hypoxic conditions and between normal pregnancies and those complicated by pre-eclampsia. In this study we aimed to examine the differences in the metabolic footprint of placental villous explants cultured at different oxygen (O(2)) tensions between women who deliver an SGA baby (n = 9) and those from normal controls (n = 8). Placental villous explants from cases and controls were cultured for 96 h in 1% (hypoxic), 6% (normoxic) and 20% (hyperoxic) O(2). Metabolic footprints were analysed by Ultra Performance Liquid Chromatography coupled to an electrospray hybrid LTQ-Orbitrap Mass Spectrometry (UPLC-MS). 574 metabolite features showed significant difference between SGA and normal at one or more of the oxygen tensions. SGA explant media cultured under hypoxic conditions was observed, on a univariate level, to exhibit the same metabolic signature as controls cultured under normoxic conditions in 49% of the metabolites of interest, suggesting that SGA tissue is acclimatised to hypoxic conditions in vivo. No such behaviour was observed under hyperoxic culture conditions. Glycerophospholipid and tryptophan metabolism were highlighted as areas of particular interest.


Subject(s)
Hypoxia/metabolism , Infant, Small for Gestational Age/metabolism , Oxygen/metabolism , Placenta/metabolism , Female , Humans , Infant, Newborn , Metabolomics/methods , Oxygen/administration & dosage , Pregnancy , Principal Component Analysis , Spectrometry, Mass, Electrospray Ionization , Tissue Culture Techniques
9.
Phys Rev Lett ; 104(13): 132003, 2010 Apr 02.
Article in English | MEDLINE | ID: mdl-20481874

ABSTRACT

By using a single formalism to handle charm, strange, and light valence quarks in full lattice QCD for the first time, we are able to determine ratios of quark masses to 1%. For m(c)/m(s) we obtain 11.85(16), an order of magnitude more precise than the current PDG average. Combined with 1% determinations of the charm quark mass now possible this gives m(s)(2 GeV)=92.4(1.5) MeV. The MILC result for m(s)/m(l)=27.2(3) yields m(l)(2 GeV)=3.40(7) MeV for the average of u and d quark masses.

10.
Placenta ; 30(11): 974-80, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19775752

ABSTRACT

Pre-eclampsia (PE) is a multi-system disorder thought to be mediated by circulating factors released from damaged placental villous trophoblast. There is extensive evidence of changes in the villous tissue in PE, some of which may be replicated by culturing villous tissue in hypoxic conditions. Metabolic footprinting offers a hypothesis-generating strategy to investigate factors released from this tissue in vitro. This study investigated differences in the factors released from villous trophoblast from uncomplicated pregnancies (n=6) and those with PE (n=6). In both cases, explanted placental villous fragments were cultured for 96 h in 1% O(2) (hypoxia) or 6% O(2) (placental normoxia). Metabolites consumed from and released into serum-conditioned culture medium were analysed by Ultra Performance Liquid Chromatography-Mass Spectrometry (UPLC-MS). The relative concentration of 154 features of the metabolic footprint were observed to change in culture medium from uncomplicated pregnancies cultured in normoxic and hypoxic conditions (p<0.00005). 21 and 80 features were also different in culture medium from PE versus uncomplicated pregnancies cultured in hypoxic and normoxic conditions, respectively (p<0.00005). When comparing all 4 groups, 47 metabolic features showed a similar relative concentration in PE-derived media cultured in normoxic conditions to conditioned media from normal villous tissue cultured in hypoxic conditions. These data suggest that hypoxia may have a role in the placental pathogenesis of PE. Three areas of metabolism were highlighted for systems biology investigation; glutamate and glutamine, tryptophan metabolism and leukotriene or prostaglandin metabolism.


Subject(s)
Hypoxia/metabolism , Metabolomics , Placenta/metabolism , Pre-Eclampsia/metabolism , Chromatography, Liquid , Culture Media, Conditioned , Female , Humans , Mass Spectrometry , Pregnancy/metabolism
11.
Ir Med J ; 102(3): 70, 72-3, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19489192

ABSTRACT

Hysterectomy is one of the most common gynaecological surgical procedures performed but there appears to be a decline in the performance of this procedure in Ireland in recent times. We set out to establish the extent of the decline of hysterectomy and to explore possible explanations. Data for hysterectomy for benign disease from Ireland was obtained from the Hospital In-Patient Enquiry Scheme (HIPE) section of the Economic and Social Research Institute for the years 1999 to 2006. The total number of hysterectomies performed for benign disease showed a consistent decline during this time. There was a 36% reduction in the number of abdominal hysterectomy procedures performed.


Subject(s)
Hysterectomy/statistics & numerical data , Ovarian Neoplasms/surgery , Uterine Cervical Neoplasms/surgery , Uterine Diseases/surgery , Female , Humans , Hysterectomy, Vaginal/statistics & numerical data , Ireland , Retrospective Studies
12.
BJOG ; 116(2): 173-81, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19076949

ABSTRACT

'Omic' technologies represent a strategy towards high-throughput, simultaneous analysis of thousands of biological molecules. Their development has been accelerated in the post-genomic era since these molecules represent the interaction of genes and environment or the 'functional genome'. Omic domains are of particular interest in the search for predictive disease biomarkers and have additional relevance in understanding pathophysiology and the development of molecularly targeted therapeutics. This review examines the fields of proteomics and metabolomics in the context of obstetrics and gynaecology, including a discussion of methodology, challenges, potential applications and current research.


Subject(s)
Metabolomics/methods , Pregnancy Complications , Pregnancy/metabolism , Proteomics/methods , Computational Biology , Female , Forecasting , Humans , Metabolomics/trends , Pregnancy Complications/diagnosis , Pregnancy Complications/metabolism , Pregnancy, High-Risk/metabolism , Proteomics/trends
13.
Ir Med J ; 101(2): 53-5, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18450251

ABSTRACT

Female sterilisation is an extensively used method of contraception all over the world but there appears to be a decline in the performance of this procedure in Ireland. There also appears to be an increased uptake of safe, long-acting contraceptive alternatives. We set out to establish the extent of the decline of laparoscopic sterilisation and to explore possible explanations. Data for female sterilisation from Ireland was obtained from the Hospital In-Patient Enquiry Scheme (HIPE) section of the Economic and Social Research Institute for the years 1999 to 2004. Recent sales figures for long acting reversible contraceptives, specifically the levo-norgestrel-loaded intrauterine system (LNG-IUS) (Mirena) and the etonogestrel implant (Implanon) were also obtained. Laparoscopic tubal ligations reduced from 2,566(1999) to 910 (2004). In the corresponding period the use of Mirena coils increased from 4,840 (1999) to 17,077 (2004).


Subject(s)
Intrauterine Devices, Medicated/statistics & numerical data , Laparoscopy/statistics & numerical data , Laparoscopy/trends , Levonorgestrel/administration & dosage , Sterilization, Reproductive/statistics & numerical data , Adolescent , Adult , Attitude of Health Personnel , Delayed-Action Preparations , Female , Health Knowledge, Attitudes, Practice , Humans , Ireland , Patient Acceptance of Health Care , Pilot Projects , Sterilization, Reproductive/methods , Sterilization, Reproductive/trends
14.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(4 Pt 1): 041102, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17994931

ABSTRACT

Path integrals similar to those describing stiff polymers arise in the Helfrich model for membranes. We show how these types of path integrals can be evaluated and apply our results to study the thermodynamics of a minority stripe phase in a bulk membrane. The fluctuation induced contribution to the line tension between the stripe and the bulk phase is computed. Also the effective interaction between the interfaces of the two phases can be computed. Explicit forms are given for this Casmir-like interaction in the tensionless case where the two phases have differing bending rigidities.

16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 73(1 Pt 1): 011906, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16486184

ABSTRACT

We consider the renormalization of the bending and Gaussian rigidity of model membranes induced by long-range interactions between the components making up the membrane. In particular we analyze the effect of a finite membrane thickness on the renormalization of the bending and Gaussian rigidity by long-range interactions. Particular attention is paid to the case where the interactions are of a van der Waals type.

17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(4 Pt 1): 041907, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15903701

ABSTRACT

We calculate the thermal Casimir effect for a dielectric tube of radius R and thickness delta formed from a membrane in water. The method uses a field-theoretic approach in the grand canonical ensemble. The leading contribution to the Casimir free energy behaves as -k(B)TLkappa(c)/R giving rise to an attractive force which tends to contract the tube. We find that kappa(c) approximately 0.3 for the case of typical lipid membrane t tubules. We conclude that except in the case of a very soft membrane this force is insufficient to stabilize such tubes against the bending stress which tends to increase the radius.


Subject(s)
Lipid Bilayers/chemistry , Membrane Fluidity , Microtubules/chemistry , Models, Chemical , Water/chemistry , Computer Simulation , Models, Biological , Stress, Mechanical , Temperature
18.
Ir Med J ; 98(2): 55-7, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15835514

ABSTRACT

To determine how women in pregnancy would like to be addressed and to ascertain their preferred choice of title during pregnancy. A questionnaire was administered to 925 antenatal women. Midwifery and medical staff (183) were invited to respond to a similar questionnaire. The response rate was 71.2% from the survey of pregnant women. The vast majority (82.1%) preferred to be addressed by their first name. Women were in favour of being called 'patient' (32.8%) as their first choice. The staff survey yielded a response rate of 77%. The majority (81.8%) of health professionals preferred to address women by their first name. 'Mother' (28.7%) was the most popular first choice. We conclude that women in pregnancy do have a preference on how they would like to be addressed and this is predominantly by first name. Health professionals also prefer to call pregnant women by their first name. The term 'patient' was the most popular first choice of title of women in pregnancy but the term 'mother' was the preferred choice of the health professionals. Medical staff were more likely to choose 'patient' than midwives.


Subject(s)
Consumer Behavior , Professional-Patient Relations , Women/psychology , Adult , Attitude of Health Personnel , Female , Humans , Ireland , Pregnancy , Surveys and Questionnaires
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 70(1 Pt 1): 011101, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15324036

ABSTRACT

In this paper we consider the calculation of the disjoining pressure of a symmetric electrolytic soap film correct to two loops in perturbation theory. We show that the disjoining pressure is finite when the loop expansion is resummed using a cumulant expansion and requires no short distance cutoff in order to give a finite result. The loop expansion is resummed in terms of an expansion in g= lB / lD where lD is the Debye length and lB is the Bjerrum length. We show that there there is a nonanalytic contribution of order g ln(g). We also show that the two-loop correction is greater than the one-loop term at large film thicknesses suggesting a nonperturbative correction to the one-loop result in this limit.

20.
Phys Rev E Stat Nonlin Soft Matter Phys ; 69(6 Pt 1): 061603, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15244581

ABSTRACT

We carry out the calculation of the surface tension for a model electrolyte to first order in a cumulant expansion about a free-field theory equivalent to the Debye-Hückel approximation. In contrast with previous calculations, the surface tension is calculated directly without recourse to integrating thermodynamic relations. The system considered is a monovalent electrolyte with a region at the interface, of width h, from which the ionic species are excluded. In the case where the external dielectric constant epsilon(0) is smaller than the electrolyte solution's dielectric constant epsilon we show that the calculation at this order can be fully regularized. In the case where h is taken to be zero the Onsager-Samaras limiting law for the excess surface tension of dilute electrolyte solutions is recovered, with corrections coming from a nonzero value of epsilon(0) /epsilon.

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