Are placental lakes of any clinical significance?

The aim of this study was to determine prospectively whether an association exists between the finding of placental lakes at the 20 week scan and an increased risk of uteroplacental complications or a poor pregnancy outcome. We studied the placental appearances in 1,198 consecutive second trimester ultrasound scans performed for routine foetal abnormality screening at our institution. The placental thickness was measured at its widest diameter in the sagittal plane and the presence or absence of placental lakes was recorded. The birth weight in each case was plotted against the centile charts in use at the hospital and recorded. Specific outcome measures included foetal growth restriction (IUGR) with a birth weight below the 5th centile, pre-eclampsia, placental abruption, and perinatal deaths. Placental lakes were seen in 17.8 per cent of the scans. There was no significant association with either maternal socio-demographic factors or perinatal mortality (OR 0.94, 95 per cent CI 0.35-2.51). No association was seen with maternal cigarette smoking (OR 1.07, 95 per cent CI 0.75-1.52), a birth weight below the 5th centile (OR 0.68, 95 per cent CI 0.39-1.18), the development of pregnancy induced hypertension (OR 0.68, 95 per cent CI 0.35-1.32), severe pre-eclampsia (OR 0.72, 95 per cent CI 0.21-2.50), or placental abruption (OR 1.79, 95 per cent CI 0.46-6.99). A finding of placental lakes was six times more likely with a thick placenta >3 cm at 20 weeks gestation (OR 6.30, 95 per cent CI 4.39 to 9.05). A finding of placental lakes during the second trimester ultrasound scan does not appear to be associated with uteroplacental complications or an adverse pregnancy outcome. The lesions are more prevalent with increasing placental thickness.

Preinduction sonographic measurement of cervical length in the prediction of successful induction of labor.

BACKGROUND: Induction of labor is carried out in approximately 20% of pregnancies. However, approximately 20% of women having induction of labor end up having a Cesarean delivery. The traditional method of predicting whether an induced labor will result in successful vaginal delivery is based on the preinduction "favorability" of the cervix as assessed by the Bishop score. However, this assessment is subjective and several studies have shown a poor predictive value for the outcome of induction. OBJECTIVES: To examine the relationship between preinduction sonographically measured cervical length and the Bishop score and to compare the two measurements in the prediction of successful vaginal delivery within 24 h of induction. METHODS: In this multicenter study, preinduction cervical assessment was undertaken in 240 women with singleton pregnancies at 37-42 weeks of gestation. The Bishop score was assessed by digital examination and the cervical length was measured by transvaginal sonography. RESULTS: Multiple regression analysis demonstrated that cervical length, Bishop score and parity provided independent contribution in the prediction of the likelihood of delivering vaginally within 24 h. Further examination of the different components of the Bishop score showed that only cervical length provided a significant contribution in the prediction of the likelihood of vaginal delivery within 24 h. In the receiver operating characteristic curves, the best cut-off point for the prediction of successful induction was 28 mm for cervical length and 3 for the Bishop score. However, cervical length appears to be a better predictor than the Bishop score, with a sensitivity of 0.87 and a specificity of 0.71 compared to 0.58 and 0.77, respectively. Similarly, the Kaplan-Meier survival curves indicate that better discriminatory results in the prediction of vaginal delivery within 24 h are achieved using cervical length rather than the Bishop score. CONCLUSION: Transvaginal sonographic measurement of cervical length provides a useful prediction of the likelihood of vaginal delivery within 24 h of induction.

Doppler fetal circulation in pregnancies complicated by pre-eclampsia or delivery of a small for gestational age baby: 2. Longitudinal analysis.

OBJECTIVE: To observe the longitudinal changes in growth, and associated Doppler measurements, of the fetal circulation in pregnancies with a normal outcome and those complicated by pre-eclampsia, birth of a small for gestational age baby, or a combination of these complications. METHODS: Two hundred and ninety-two women had serial ultrasound scans performed from the 24th week of pregnancy. Measurements obtained included: the abdominal circumference, umbilical artery pulsatility index, the middle cerebral artery pulsatility index and time-averaged velocity, and the thoracic aorta pulsatility index and time-averaged velocity. Outcome measures included the birth of a small for gestational age infant, pre-eclampsia or a combination of these complications. RESULTS: One hundred and sixty-seven pregnancies ended in the normal birth of an appropriately grown infant at term, while 105 had a complicated outcome. They were divided into three categories: preeclampsia only (i.e. with the birth of an appropriately grown fetus, n = 13); small for gestational age only with no evidence of pre-eclampsia, n = 55; and pre-eclampsia complicated by the birth of a small for gestational age infant, n = 37. The group with pre-eclampsia complicated by small for gestational age was closest in characteristics to true clinical intrauterine growth restriction. A reduction in the abdominal circumference mirrored a rise in the umbilical artery pulsatility index and preceded changes in the middle cerebral artery and thoracic aorta. The greatest degree of change in the fetal circulation was observed during the three weeks preceding delivery. Ratios of the values obtained from the fetal and umbilical circulation demonstrated the greatest deviation from normal. CONCLUSIONS: A reduction in fetal growth velocity preceded changes observed in the fetal circulation. Ratios of the fetal Doppler parameters provided the clearest evidence of deterioration in the fetal condition. The information provided may be of use in the diagnosis and management of the growth-restricted fetus.

Effect of routine screening for Down's syndrome on the significance of isolated fetal hydronephrosis.

OBJECTIVE: To determine the risk of Down's syndrome in fetuses with isolated hydronephrosis at 18-23 weeks in an unselected general population after routine screening for Down's syndrome, using first trimester nuchal translucency measurement and second trimester maternal serum biochemistry. POPULATION: All pregnant women undergoing a routine 18-23 week ultrasound scan, from a population who had been offered screening for Down's syndrome. SETTING: A district general hospital serving a low risk obstetric population. METHODS: Prospective study of all routine 18-23 weeks ultrasound scans. The prevalence of isolated hydronephrosis and Down's syndrome was determined and the relative risk for Down's syndrome was calculated for different ultrasound findings. RESULTS: 10,971 women were scanned at 18-23 weeks during the study period. Down's syndrome was diagnosed in 14 of 20 cases before this stage using first trimester nuchal translucency measurement and second trimester maternal serum biochemistry. Isolated fetal hydronephrosis was diagnosed in 423 pregnancies (3.9%); none of these pregnancies were affected by Down's syndrome. The relative risk for Down's syndrome was 0.18 (95% CI 0.06-0.53) for women with a normal scan (n = 9983). When multiple ultrasound markers were found (n = 565), the relative risk for Down's syndrome was 2.00 (95% CI 0.18-22.10) and 9.00 (95% CI 1.14-71.30) for all other aneuploidies. CONCLUSION: The finding of isolated fetal hydronephrosis does not significantly increase the age-related risk for Down's syndrome. The presence of multiple ultrasound markers is associated with an increased risk of aneuploidies other than Down's syndiome. These findings are explained by the reduced prevalence of Down's syndrome as a result of prior screening and diagnosis of this condition.

The value of routine endometrial biopsy in gynaecological practice in Nigeria.

A review of 7,211 endometrial biopsy reports in a University Teaching Hospital in Nigeria, over a 6 year period revealed that 90.5% of samples from 5,795 patients with infertility and 83.4% of 1,416 patients with abnormal uterine bleeding were essentially normal. The yield for tuberculosis endometritis (0.49%) and uterine corpus malignancy (0.58%) was low. Eighty percent of patients with uterine malignancy were aged 40 years and above. In an era of medical audit and scarce human and financial resources, the wisdom of routine endometrial biopsy in all women with infertility and those with abnormal uterine bleeding who are younger than 40 years, is called to question.

PIP: To evaluate the need for continued performance of endometrial biopsy in all patients with infertility and abnormal uterine bleeding in Nigeria (a country with both low rates of endometrial malignancies and declining health care resources), pathology reports of 7211 endometrial biopsies conducted at University College Hospital in Ibadan in 1984-89 were reviewed. The majority of specimens examined--5795 (80.36%)--were from infertile patients; 90.5% of these samples were essentially normal and secretory phase endometrium was found in 80.2%. 83.4% of women with abnormal uterine bleeding had normal endometrium. The yield of tuberculosis endometrium was 0.49%, while that of uterine corpus malignancy was 0.58%. Among the latter group of patients, 80% were aged 40 years and older. These findings suggest that many women with infertility and abnormal uterine bleeding are subjected to unnecessary curretages whose results do not influence the course of management. In developing countries with few trained histopathologists, careful selection of patients for endometrial biopsy (especially those under 40 years of age) is recommended.

Feet of Clay over frilly caps issue.

I am delighted to see Trevor Clay back in harness (Nursing Standard September 12 1990). I found the column interesting and challenging. I hope there will be much discussion in the future about autonomy and teamwork.