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R F Lamont

Publications and source records attributed to R F Lamont.

At least 37 records · Page 2Linked to original sources
PubMed1999

The prevention of preterm birth with the use of antibiotics.

UNLABELLED: Infection is a well recognised cause of spontaneous early preterm labour. Preterm labour of infective aetiology is refractory to the use of tocolytic agents and affected women have a higher risk of subsequent chorio-amnionitis and neonatal infection. Antibiotics used prophylactically for the prevention of preterm labour are more likely to be successful if given systemically. Intravaginal antibiotics are only likely to be of benefit if they are used early in the second trimester and in those women in whom there is full expression of abnormal genital tract flora (grade III bacterial vaginosis on Gram stain of vaginal secretions). Antibiotic treatment for women far removed from term offers significant benefit with respect to pregnancy prolongation. The value of extended antibiotic treatment is unclear since this may lead to the development of resistant bacterial strains. CONCLUSION: The evidence with respect to the use of antibiotics for women in preterm labour is inconsistent though there is a trend toward benefit.

Anti-Bacterial Agents↗
PubMed1999

A comparison of the use of Papanicolaou-stained cervical cytological smears with Gram-stained vaginal smears for the diagnosis of bacterial vaginosis in early pregnancy.

Our objective is to compare the efficacy of using Papanicolaou (PAP)-stained cervical cytology smears with a standardized method of interpreting Gram-stained vaginal smears for the diagnosis of bacterial vaginosis (BV) in pregnancy. High vaginal smears were Gram-stained and examined by a single observer to characterize 3 grades of vaginal flora and diagnose BV. Cervical smears were PAP-stained and examined for characteristic patterns of vaginal flora including evidence of BV by either a number of cytotechnicians or a single cytopathologist. The results of the 2 methods were compared. Seven hundred and forty-seven women attending an antenatal clinic in a district general hospital who consented to have a smear of vaginal secretions and cervical cytology in early pregnancy. The main outcome measure is the diagnosis of BV by different methods in a pregnant population. Compared with the Gram-stain method for the diagnosis of BV, there was good agreement between PAP-stain interpretation by a single observer but the agreement was not as good with PAP-stain interpretation by multiple cytotechnicians. When the grades were consolidated to normal (grade I) and abnormal flora (grades II and III), compared to Gram-stained smears, PAP cytology undertaken by several cytotechnicians had a sensitivity of 80.7% and a specificity of 90.7%. The sensitivity and specificity increased to 87% and 97%, respectively, when the PAP-stained smears were read by a single cytopathologist. Using kappa scores, only those readings made by a single cytopathologist were reliable. The setting in a cytopathology laboratory comprises multiple cytotechnicians, so that PAP-stain analysis of vaginal smears for the diagnosis of BV is likely to provide results which are less reliable than those obtained by Gram staining. The latter should be the first choice and every effort should be made to set up this service.

Cervix Uteri↗
PubMed1998

Bacterial vaginosis: its importance in obstetrics.

Bacterial vaginosis is associated with adverse sequelae, including late miscarriage, preterm prelabour rupture of the membranes, chorioamnionitis, postpartum endometritis and preterm labour and delivery. It is easy to diagnose and treat; intervention reduces the incidence of adverse sequelae. Symptomatic women and those who are at increased risk of infectious morbidity should be screened.

Abortion, Spontaneous↗
PubMed1997

Relationship between hydrogen peroxide-producing strains of lactobacilli and vaginosis-associated bacterial species in pregnant women.

This study was conducted to determine the relationship between lactobacilli and bacterial species associated with bacterial vaginosis in pregnancy and the prevalence of H2O2-producing and non-producing strains of lactobacilli in pregnant women whose vaginal flora had already been analysed. Information was available for 174 pregnant women whose vaginal flora had been evaluated previously by examining gram-stained vaginal smears: 50 had grade III flora (bacterial vaginosis). 50 grade II flora, 41 flora graded as abnormal which then reverted to grade I (revertants) and 33 normal flora (controls). Lactobacilli were isolated from 19 of 50 women whose vaginal flora was grossly abnormal culturally and categorised as grade III by Gram staining. In 6 of these 50 women lactobacilli were isolated in large numbers, i.e. 10(5)-10(6) cfu/ml. H2O2-producing strains of lactobacilli were isolated from 11 of 12 women with grade III flora who were randomly selected from this group. Thus, in those 11 women it appears that H2O2-producing lactobacilli had not protected them from developing bacterial vaginosis. Bacterial species associated with vaginosis were isolated in high numbers from a large proportion of women in the revertant and grade II groups in association with high counts of lactobacilli. Thus, in some women it is possible that a change to an abnormal flora could occur before the complete disappearance of lactobacilli. It is concluded that bacterial vaginosis may develop in some women despite the presence of H2O2-producing strains of lactobacilli and that other factors, as yet unidentified, might be conducive to the appearance of abnormal bacterial flora with progression to vaginosis.

Bacteria↗
PubMed1996

Bacterial vaginosis in pregnancy: distribution of bacterial species in different gram-stain categories of the vaginal flora.

Vaginal swabs for microbiological culture were taken from 174 pregnant women whose vaginal flora had been evaluated by Gram's stain; 50 had grade III flora (bacterial vaginosis, BV), 50 grade II (intermediate), 41 had vaginal flora graded as abnormal which then reverted to grade I (revertants) and 33 had normal flora (controls). The aim was to determine whether bacterial species isolated from women with grade II flora differed from those with grade III flora. Isolation of Lactobacillus spp. decreased from grade I to grade III and that of other aerobic and anaerobic bacterial species increased. There was little difference in the species isolated from women with grade II and grade III flora, but there was a distinct order in which organisms in different species increased in numbers. The vaginal flora of revertants was intermediate between that of healthy controls and those with grade II flora. Coagulase-negative Staphylococcus spp. were isolated from a greater number of revertants than grade I controls but the incidence did not increase in grade II or grade III. Bifidobacterium spp. were isolated from a greater number of revertants than grade I controls and increased further in grade II and grade III. However, Gardnerella vaginalis and Mycoplasma hominis were isolated from a much larger number of women with grade III flora than the other groups. The conclusion is that grade II is a transitional phase between grade I and grade III and that some organisms such as G. vaginalis and M. hominis only reach large numbers in the late stage. The sequence of appearance of the various bacterial species may be a result of the pathophysiological alteration of the vaginal ecosystem associated with BV.

Bacteria↗
PubMed1996

Comparison of Gram-stained smears prepared from blind vaginal swabs with those obtained at speculum examination for the assessment of vaginal flora.

OBJECTIVE: To determine whether Gram-stained smears obtained from blind vaginal swabs could be used reliably for the assessment of the vaginal flora. DESIGN: A prospective, blind comparative study. SETTING: The antenatal clinic of a district general hospital. PARTICIPANTS: Eighty-eight women examined and screened for the presence of bacterial vaginosis during their first antenatal clinic visit. Two smears were obtained for each woman, the first prepared from a vaginal swab taken blindly and the second at speculum examination. The smears were Gram-stained and classified according to the Nugent score: Grade 1 (normal), Grade 2 (intermediate), Grade 3 (bacterial vaginosis). RESULTS: Eight of the 88 pregnant women were identified as having bacterial vaginosis on the basis of the smear taken at speculum examination, and these were correctly identified as having bacterial vaginosis by smears prepared from the blindly taken swab. This gives the blind vaginal swab technique for detecting bacterial vaginosis a sensitivity and specificity of 100% when compared with swabbing at speculum examination. The flora of two women were graded as intermediate, and of 75 as normal by both techniques. Only in three cases was there a disparity between the two techniques, a difference that was not statistically significant (kappa = 0.8546, 95% CI 0.6945 to 1.0). CONCLUSIONS: Vaginal smears prepared from correctly taken blind vaginal swabs can be used to assess the vaginal flora and screen for bacterial vaginosis. This method could be used in epidemiological studies of bacterial vaginosis in the general population and for screening antenatal populations for abnormal vaginal flora.

Double-Blind Method↗
PubMed1994

Abnormal bacterial colonisation of the genital tract and subsequent preterm delivery and late miscarriage.

OBJECTIVE: To find out whether women with bacterial vaginosis detected early in pregnancy are at increased risk of preterm delivery. DESIGN: Prospective description cohort study. SETTING: Antenatal clinic in a district general hospital. SUBJECTS: 783 women examined during their first antenatal clinic visit and screened for recognised risk factors for preterm delivery and the presence of bacterial vaginosis or intermediate abnormal flora detected by examination of a vaginal smear stained by Gram's method. MAIN OUTCOME MEASURES: Gestational age at delivery classified as late miscarriage (16-24 weeks' gestation), preterm delivery (24-37 weeks' gestation), term delivery (> or = 37 weeks' gestation). RESULTS: Multiple logistic analysis showed that there was an increased incidence of preterm delivery in women with a previous preterm delivery (9/24; odds ratio 25; 95% confidence interval 9 to 70; P < 0.001) and bacterial vaginosis (9/115; 2.8; 1.1 to 7.4; P = 0.04). A further logistic analysis of data from women recruited before 16 weeks' gestation showed that preterm deliveries or late miscarriages occurred more often in women with bacterial vaginosis (12/77; 5.5; 2.3 to 13.3; P < 0.001). CONCLUSIONS: Late miscarriage and preterm delivery are associated with the presence of bacterial vaginosis in early pregnancy. This is independent of recognised risk factors such as previous preterm delivery.

Abortion, Spontaneous↗
PubMed1994

A longitudinal study of bacterial vaginosis during pregnancy.

OBJECTIVE: To determine the longitudinal changes in the incidence of vaginosis in pregnancy. DESIGN: A prospective study of women during pregnancy. SETTING: A District General Hospital in North-West London. SUBJECTS: Seven hundred and eighteen pregnant women attending antenatal clinics. At their first attendance and subsequently, Gram-stained vaginal smears were examined and Mycoplasma hominis and Gardnerella vaginalis were sought by culture. RESULTS: Initially, 87 (12%) women had bacterial vaginosis diagnosed on Gram-stained reading of the vaginal smears. Examination of further smears, obtained from 176 women at 36 weeks of gestation, showed that those whose vaginal flora was normal initially, and who went to term, rarely developed vaginosis (three of 127, 2.4%). Samples were obtained at 36 weeks gestation from 32 women who had bacterial vaginosis initially, and went to term. In almost 50% (15 of 32) of these a normal lactobacillus-dominated flora had regenerated. Thirty-five women (5%) had initial vaginal smears graded as intermediate. From this group, six of the 17 (35%) women from whom samples were obtained at 36 weeks gestation still had flora of an intermediate pattern; 10(59%) now had normal flora and only one (6%) had developed bacterial vaginosis. Women with bacterial vaginosis were more likely to be culture-positive for M. hominis than those with normal flora (34/78 versus 10/563, odds ratio 42.73 (18.9 to 102.3) P < 0.001), or to be culture-positive for G. vaginalis than those with normal flora (35/78 versus 21/563, odds ratio 21.0 (10.75 to 41.2) P < 0.001). CONCLUSION: Pregnant women do not commonly develop bacterial vaginosis after 16 weeks gestation, and if present, it remits spontaneously in approximately half of those who reach term. As bacterial vaginosis is associated with increased rates of second trimester miscarriage and preterm delivery, any treatment aimed at its eradication in pregnancy should be given no later than the beginning of the second trimester of pregnancy.

Adult↗
PubMed1992

Diagnosis of bacterial vaginosis in a gynaecology clinic.

OBJECTIVE: To estimate the prevalence of bacterial vaginosis in women referred to a gynaecology clinic, and to compare two methods of diagnosing bacterial vaginosis. SETTING: Gynaecology Clinic at Northwick Park Hospital SUBJECTS: 114 women aged 16 to 65 referred consecutively to the gynaecology clinic of one consultant. MAIN OUTCOME MEASURES: Detection of bacterial vaginosis by standard compound criteria and by examination of a Gram stained smear of fluid from the posterior vaginal fornix. RESULTS: Bacterial vaginosis was detected by both the Gram stain and the compound criteria in 13 women. There was no correlation between the symptom of vaginal discharge and the diagnosis of bacterial vaginosis in this population, but the presence of discharge noted by the clinician was associated with bacterial vaginosis. CONCLUSIONS: The prevalence of bacterial vaginosis was 11%. The Gram stain provides a simple and inexpensive method for laboratory confirmation of bacterial vaginosis where facilities for using the compound criteria are not available.

Adolescent↗
PubMed1991

Edwards' syndrome after the replacement of cryopreserved-thawed embryos.

A case of Edwards' syndrome after the replacement of frozen-thawed embryos is reported. The presence of cardiac abnormalities and limb deformities raised the suspicion of chromosomal abnormality. The diagnosis of trisomy 18 was made by cytogenetic analysis of fetal blood from the umbilical vein. The chromosomal nondisjunction might have been spontaneous or because of freezing and thawing. If it occurred as a result of freezing and thawing, it is more likely that this was at the first cleavage division rather than the second meiotic division because the embryos were frozen at the late pronuclear stage. Unfortunately, there were no karyotypic markers in the couple's chromosomes to time the nondisjunction. The wisdom of using donor oocytes in an ovum donation program from patients with long-standing infertility is questioned.

Abnormalities, Multiple↗
PubMed1991

Intrauterine pressures in labours induced by amniotomy and oxytocin or vaginal prostaglandin gel compared with spontaneous labour.

Uterine activity during the first stage of labour was measured by an intrauterine transducer in 22 women induced with intravaginal PGE2 gel, in 37 induced by amniotomy and intravenous oxytocin, and in nine women in spontaneous labour. The nulliparous women in the PGE2 gel group had a significantly longer pre-established phase of labour and a significantly shorter established phase than nulliparae induced by amniotomy and oxytocin. The mean levels of total uterine activity (kPas) during labour and the uterine activity integrals (kPas/15 min) were significantly lower in nulliparae induced with PGE2 gel than in those induced by amniotomy and oxytocin. These findings suggest that PGE2 gel has a positive, beneficial effect on cervical compliance during the pre-established phase, resulting in less myometrial effort during established labour. These effects were less evident in parous women, probably because of an innate lower cervical resistance due to their previous labours. Uterine activity patterns during the 4 h leading to full cervical dilatation in nulliparae were similar in labours induced with PGE2 gel and spontaneous labours, whereas labours induced by amniotomy and oxytocin exhibited a significantly different pattern. Expulsion of the fetus during normal labour is a function of both uterine contractions and a decrease in the cervical resistance and the data suggest that induction by PGE2 gel more closely mimics spontaneous labour, whereas the predominant effect of oxytocin is to stimulate myometrial activity.

Amnion↗