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J M Pearce

Publications and source records attributed to J M Pearce.

At least 163 records · Page 9Linked to original sources
PubMed1991

[Correlation between the results of Doppler velocimetry with spectral analysis and the viscosity of cord blood].

The contribution of rheological factors to be impedance of blood flow in the umbilical artery as determined by continuous wave Doppler ultrasound was investigated. Of the 51 pregnancies recruited, six were complicated by pre-eclampsia, 10 by intrauterine growth retardation, 15 by both pre-eclampsia and fetal growth retardation, and there were 20 controls. A significant correlation was demonstrated between both plasma viscosity and gestational age and the resistance index used to characterize the Doppler waveform. Multiple regression analysis demonstrated that changes in plasma viscosity explained 55 p. cent of the variance seen in the resistance index and that this was statistically significant. This finding is, however, unlikely to be of clinical significance as whole blood viscosity had an insignificant effect on the impedance in the umbilical artery. We postulate that vascular factors such as the number and calibre of the placenta arterioles are a more important determinant of umbilical artery impedance.

Blood Flow Velocity↗
PubMed1991

Analysis of phospholipids in human amniotic fluid by 31P NMR.

A recently described solvent-reagent system for obtaining narrow linewidths in 31P NMR spectra of phospholipid extracts was applied to human amniotic fluid. Resolution of the major components was achieved by manipulating the solvent composition, and assignments were made by spiking samples with standard compounds. Spin-lattice relaxation times were determined and used to optimize data acquisition. NMR estimates of the phosphatidylcholine to sphingomyelin ratio for 33 patients were compared to those obtained by TLC densitometry, a common clinical assay for fetal pulmonary maturity. Estimates of the levels of phosphatidylglycerol and phosphatidylinositol could also be obtained from 31P NMR. High-resolution 31P NMR in this solvent-reagent system provides a relatively straightforward and reliable alternative method for assessing fetal pulmonary status by phospholipid quantitation in human amniotic fluid. The 31P NMR method has the advantage that it is sensitive to total, and not just unsaturated, phosphatidylcholine.

Amniotic Fluid↗
PubMed1991

A comparison of Doppler flow velocity waveforms, amniotic fluid columns, and the nonstress test as a means of monitoring post-dates pregnancies.

Five hundred thirty-four pregnancies exceeding 294 days were monitored by weekly sonographic estimations of amniotic fluid columns, daily maternal recordings of fetal movements, and thrice-weekly nonstress tests. In addition, each woman received twice-weekly studies of the uteroplacental and umbilical circulations by means of Doppler ultrasound. There were no fetal deaths in the study. Of the individual methods of fetal surveillance, absence of end-diastolic frequencies in the umbilical artery was the most sensitive, predicting 91% of fetuses who developed fetal distress in the first stage. Combining the test with sonographic estimation of amniotic fluid columns improved the prediction to 100%, with only a minimal fall in the specificity. These results strongly suggest that a combination of umbilical artery Doppler waveforms and amniotic fluid determinations is an adequate method of monitoring the post-dates pregnancy.

Adult↗
PubMed1991

Sensory urgency: how full is your bladder?

OBJECTIVE: To investigate whether women with sensory urgency have an abnormal perception of bladder fullness. DESIGN: Prospective observational study. SETTING: Urodynamic Unit, St George's Hospital, London. SUBJECTS: 15 women with sensory urgency, 15 women with idiopathic detrusor instability and 15 without symptoms of frequency or urgency (control group). INTERVENTIONS: All the women attended for cystometry. Each was asked to complete a visual analogue score of how full she perceived her bladder to be on a scale from 1 to 10. This was done before filling cystometry and at three times during bladder filling. At each time actual filled volume was noted. MAIN OUTCOME MEASURES: Maximum bladder capacity and individual perception of bladder fullness. RESULTS: Women with sensory urgency and detrusor instability had similar maximum bladder capacity although values in both groups were significantly lower than in the control group; thus percentage of maximum bladder capacity was used for analysis. Linear regression was performed for each group of patients and a predicted visual analogue score at 25, 50 and 75% of capacity calculated. These were compared between groups by rank analysis of variance. There was no significant difference between sensory urgency and detrusor instability. However, at 25, 50 and 75% of capacity, both groups had a significantly higher score than the control group. CONCLUSIONS: This abnormal perception would explain symptoms of frequency and urgency in these two groups. These results also confirm the similarity between detrusor instability and sensory urgency.

Adult↗
PubMed1991

Polycystic ovary syndrome and bulimia.

One hundred fifty-three patients classified as suffering from polycystic ovarian syndrome (PCOS) and 109 patients who were suffering from a clear organic disorder or endocrinopathy received the bulimia investigation test (Edinburgh) (BITE) questionnaire for abnormal eating behaviors. Patients with PCOS showed a significant increase in their mean BITE score for approximately a third had abnormal eating patterns, and 6% have scores suggestive of clinical bulimia compared with only 1% of women in the group with organic endocrinopathies. The work suggests that women with PCOS should be screened for abnormal eating behaviors and raises the possibility that treatment by psychological means should be considered when abnormal eating behaviors are present.

Analysis of Variance↗
PubMed1990

Whiplash injury.

Explore the source record for details and available documents.

Chronic Disease↗
PubMed1990

Early Doppler ultrasound screening in prediction of hypertensive disorders of pregnancy.

1198 nulliparous women were screened in early pregnancy (median 18 weeks' gestation) by the recording of doppler ultrasound waveforms from the uteroplacental circulation. After exclusions, the results of 1014 women were available for analysis; 118 (12%) of them had persistently abnormal waveforms on repeat ultrasound scans at 24 weeks and were taken to have a positive test result. Hypertension was significantly more frequent among those women than among women with normal doppler waveforms (29/118 [25%] vs 45/896 [5%]). In addition, hypertension in women with abnormal waveforms was more likely to be severe; 12 (10%) had proteinuria and 15 (13%) intrauterine growth retardation compared with 7 (0.8%) and 0, respectively, of those with normal waveforms. Overall, the test did poorly when assessed by standard statistical means. However, the sensitivity was high for hypertension associated with either proteinuria (63%) or intrauterine growth retardation (100%). The test is cheap, easy to carry out, and non-invasive, and it can be done in early pregnancy; it is therefore a useful means of identifying a high-risk group of pregnant women suitable for therapeutic intervention to reduce the incidence of hypertensive disorders and their complications.

Adult↗
PubMed1990

Doppler ultrasound and aspirin in recognition and prevention of pregnancy-induced hypertension.

Screening of 1226 nulliparous women by means of doppler uteroplacental flow-velocity waveforms in early pregnancy identified 148 (12%) as being at high risk of pregnancy-induced hypertension. After exclusions and refusals, 100 women were randomly allocated to groups receiving either low-dose aspirin (75 mg daily; 48 patients) or identical placebo (52 patients) for the remainder of the pregnancy. The difference between the aspirin and placebo groups in the frequency of pregnancy-induced hypertension (13% vs 25%) did not achieve significance, but there were significant differences in the frequencies of proteinuric hypertension (2% vs 19%) and hypertension occurring before 37 weeks' gestation (0% vs 17%). Fewer aspirin-treated than placebo-treated women had low birthweight babies (15% vs 25%), but this difference was not significant. The only perinatal death in the aspirin group followed a cord accident during labour, whereas the 3 perinatal deaths in the placebo group were all due to severe hypertensive disease. No maternal or neonatal side-effects were observed in either group.

Administration, Oral↗
PubMed1990

Recurrent spontaneous abortion and polycystic ovarian disease: comparison of two regimens to induce ovulation.

OBJECTIVE: To determine whether pituitary suppression before induction of ovulation reduces the rate of spontaneous abortion in women with polycystic ovarian disease and primary recurrent spontaneous abortions. DESIGN: Closed, randomised, sequential trial. Pairs of women were allocated to each treatment by the toss of a coin. SETTING: Supraregional clinic for women who had had recurrent spontaneous abortions. SUBJECTS: Forty two women with polycystic ovarian disease and primary recurrent spontaneous abortions. INTERVENTIONS: Ovulation was induced by clomiphene or pituitary suppression with buserelin followed by pure follicle stimulating hormone. MAIN OUTCOME MEASURES: Preference for a particular treatment was noted. A preference occurred when one woman in a pair had a successful pregnancy (defined as one of over 12 weeks' gestation) and one had a spontaneous abortion; the preference was for the treatment resulting in the successful pregnancy. RESULTS: Spontaneous abortions occurred in 11 of 20 women given clomiphene compared with two of 20 who had pituitary suppression. Eleven preferences were found for buserelin and two for clomiphene. In seven pairs both women had successful pregnancies. One pair was discarded because one of the women did not become pregnant. The ratio of luteinising hormone concentration to follicular diameter was found to be a possible diagnostic indicator of spontaneous abortion. CONCLUSION: Pituitary suppression before induction of ovulation significantly reduces the risk of spontaneous abortion in women with polycystic ovarian disease and primary recurrent spontaneous abortions.

Abortion, Habitual↗
PubMed1990

The clinical implications of absent or reversed end-diastolic frequencies in umbilical artery flow velocity waveforms.

We describe the clinical details of 37 pregnancies with loss or reversal of end-diastolic frequencies in the umbilical artery, as detected by Doppler ultrasound. This finding is an ominous sign of serious fetal compromise in the majority of cases, with a high incidence of growth retardation, oligohydramnios, preterm delivery and maternal hypertension. However, current knowledge does not indicate when these pregnancies should be delivered. The possible pathophysiology and available literature are discussed.

Blood Flow Velocity↗