The Prevalence and Timing of Obstetric Ultrasound in Victoria 1991–1992: a Population-based Study

Summary: A statewide study to ascertain the number of ultrasound scans received by women in pregnancy, to identify the proportion having a scan at 16 to 20 weeks' gestation, and to establish where the scan at 16 to 20 weeks was performed was carried out between January, 1991 and June, 1992 in Victoria. Additional data were collected by midwives and entered on the perinatal morbidity statistics form routinely completed for all births. Of 52,319 women providing responses, 3.1% did not have a scan. Of the remaining 96.9% who had a scan, 73.5% were scanned at 16 to 20 weeks'gestation. Predictors of not having a scan were maternal birthplace and higher parity: previous perinatal death(s), and attendance at nonteaching hospitals predicted the opposite. Predictors of being scanned were location of hospital (country), maternal birthplace, higher parity and maternal age (< 20 years). Substantial differences in frequency and timing were found between hospitals attended. Factors associated with the pattern of scanning are not readily explicable in terms of risk of malformations or women's choices.     

Episiotomy at the Royal Women's Hospital, Brisbane: a comparison of practices in 1986 and 1992

Objective: to determine whether the incidence of perineal outcomes, including episiotomy, at the Royal Women's Hospital (RWH) Brisbane reflected trends reported in the literature.Design: retrospective record review.Setting: RWH Brisbane.Participants: 953 women who delivered vaginally at the RWH in 1986 and 1992.Measurements and findings: there was a decline in the episiotomy rate from 65% in 1986 to 36% in 1992. This was accompanied by an increase in the incidence of intact perinea and spontaneous perineal tears. There was no difference in the incidence of spontaneous third degree tears. The decline in the incidence of episiotomy was found when other factors, such as parity, were considered, with the exception of operative vaginal delivery, where no difference in the use of episiotomy was found. There was no significant increase in the number of babies with an Apgar score of <7 at one minute of age, despite a significant reduction in the use of episiotomy when delivering these babies (55% in 1986 and 19% in 1992; P<0.001). The second stage was significantly longer in 1992 (P<0.01).Key conclusions: the findings reflect the decline in the incidence of episiotomy reported in the literature. This decline in rate was accompanied by an increase in the length of second stage and in the incidence of both intact perinea and perineal tears. Lowering the incidence of episiotomy did not result in a rise in the rate of babies with an Apgar score of <7 at one minute.     

Psychosocial factors influencing teenage sexual activity, use of contraception and unplanned pregnancy

Objective: to compare teenagers who become unintentionally pregnant and teenagers who have never been pregnant but are using contraception on matters related to family/partner stability, and communication with a parent or stable sexual partner about sexual matters.Design: survey utilising self-completed questionnaire.Setting: a hospital antenatal clinic and community-based family planning clinic.Participants: 30 teenagers with an unplanned pregnancy and 31 ‘never-pregnant’ teenagers using contraception.Findings: the two groups were similar on demographic factors, mean age at which sexual intercourse was first experienced, total number of sexual partnerships, the number of teenagers having a current, regular boyfriend and mean length of the interval between when the teenagers first started going out with their boyfriend and when first sexual intercourse took place. Teenagers in the family planning clinic group were more likely to be living with both natural parents and to be still at school or in higher education. The mean length of time pregnant teenagers had been going out with their boyfriend was longer, they were more likely to be cohabiting with him and to be unemployed. Participants from the antenatal clinic group communicated more with their mothers about sexual matters than those in the family planning clinic group, who were more likely to seek this information from books. The family planning clinic participants were more likely to discuss personal rules and values with friends than those in the antenatal clinic group.Implications for practice: to develop understanding of factors predisposing to unplanned pregnancy during adolescence and to implement measures to counter them, further studies to examine the influence of teenagers' perceptions of family relationships and future life prospects on contraception use and unplanned pregnancy were identified.     

Localizing chlamydial infection in cervical biopsies with the immunoperoxidase technique

One hundred and two cervical biopsy specimens containing varying degrees of chronic inflammation were stained for chlamydial antigens with the immunoperoxidase technique. Seven cases (6.9%) were positive. Histologically, six (84%) of the Chlamydia-positive cases contained severe chronic inflammation, all contained reparative atypia, and two (28%), follicular cervicitis. When evaluated separately, 22% (six of 27) of the specimens with severe inflammation were positive in contrast to 0% (0 of 45) of cases with mild inflammation. Positively staining cells were located primarily in columnar epithelium and reparative atypia and occasionally in areas of immature squamous metaplasia. The cytological finding which correlated with positive staining was cytoplasmic vacuolation; however, cytoplasmic vacuoles were common in cells which did not stain positively, and it was impossible to predict on histological grounds which cells/specimens would stain positively by immunoperoxidase. Because of these findings, the presence of chlamydial infection should be strongly suspected whenever the cervical biopsy specimen contains severe inflammation and repair. Although tissue staining may not be as sensitive as culture for diagnostic purposes, it can be performed rapidly and simply and may be a useful special stain in cases where the diagnosis of chlamydial infection is not suspected clinically or cultures are not immediately available.     

Human papillomavirus infection and cervical neoplasia: new perspectives

This review addresses several problems associated with human papillomavirus (HPV) infection of the cervix and lower female genital tract. These include the definition of HPV infection and its distinction from HPV-associated neoplasia, the distinction of HPV infection from reactive epithelial changes induced by other infections, and the transmission of HPV infection via the male partner. The available evidence indicates that there are two distinct intraepithelial processes in the cervix associated with HPV. One is the classical condyloma and its counterpart in immature epithelium, atypical immature metaplasia. The other is intraepithelial neoplasia, which, like classical infection, may be mature [cervical intraepithelial neoplasia (CIN) with koilocytosis] or immature (high grade CIN or carcinoma in situ). Molecular hybridization studies indicate that HPVs 6 and 11 are most commonly detected in the former, whereas HPVs 16 and 18 DNA are most common in the latter and in invasive cancer. From the clinical standpoint the most important distinction is between HPV-related disease (condyloma or CIN) and reactive changes associated with other pathogens, such as Chlamydia. The former should be removed from the cervix, whereas the latter should be treated medically or followed. It is stressed that therapy should not hinge upon the histological distinction of HPV infection from neoplasia and that all lesions should be removed, by conservative means if possible. This is underscored by the fact that a high proportion of CIN lesions contain areas identical to condyloma and that lesions with deep endocervical canal involvement, including those with features suggesting condyloma, should be treated by cone biopsy to exclude the presence of invasive cancer. Histological classifications for nonneoplastic, HPV-infected, and neoplastic epithelium are proposed. The management of the male partner is still unsettled. However, a large proportion of male partners of these patients have penile lesions and should be included in diagnostic and therapeutic protocols of women with genital HPV infections or neoplasms.     

Human papilloma virus infection (condyloma) of the cervix and cervical intraepithelial neoplasia: a histopathologic and statistical analysis

Two hundred fifty consecutive cases previously diagnosed as advanced intraepithelial neoplasia (CIN 2 and CIN III) were reviewed and examined for the presence of coexisting condyloma. When the mean ages and age distributions were analyzed, there was a consistent shift of the age distribution to a younger age among women with CIN and condyloma as opposed to CIN alone. Furthermore, when the relationship between age and case accumulation was normalized from a curvilinear to a linear relationship, there were significant differences in the slope of the accumulation rate between cohorts of CIN III with and without condyloma. These differences suggest that the concordant observation of both lesions in a given patient is not a random process resulting from two independent events but rather indicates an underlying dependence between the two (i.e., condyloma and CIN). It cannot, however, be determined statistically whether the associated condyloma is directly responsible for the CIN lesion or hastens its transit time.     

Effects of a mixture of two insecticides in freshwater microcosms: I. Fate of chlorpyrifos and lindane and responses of macroinvertebrates

Effects of chronic application of a mixture of the insecticides chlorpyrifos and lindane were studied in indoor freshwater microcosms. The exposure concentrations (based on 0, 0.005, 0.01, 0.05, 0.1 and 0.5 times the LC50 of the most sensitive standard test organism for each compound) were kept at a constant level for four weeks. The calculated mean concentrations for chlorpyrifos were found to be almost at their corresponding nominal level during the treatment period. The mean calculated lindane concentrations, however, were found to be 15–40% higher than intended. In the post treatment period both insecticides dissipated fast (t _1/2: chlorpyrifos 9 days, lindane 22 days) from the water phase. The concentrations of the mixture at the highest treatment level corresponded to 0.53 toxic units (TU) for Daphnia magna and 0.61 TU for the most sensitive fish. The decomposition of Populus leaves in litter bags was significantly lower at the three highest insecticide concentrations. The macroinvertebrate community was seriously affected at the three highest treatment levels, with Crustacea and the Chironomidae Corynoneura proving to be the most sensitive groups. Gastropoda and Oligochaeta were relatively insensitive and some taxa (e.g. Valvata piscinalis, juvenile Physa fontinalis, Nemertea and Stylaria lacustris) increased in numbers. The observed effects could be explained from the individual toxicity of the insecticides to the invertebrates, and did not indicate synergistic effects. A second paper (Van den Brink et al., 2002) addresses the effects on other endpoints, as well as the overall risk assessment of the insecticide mixture.