Estimation of fetal weight by ultrasound prior to 33 weeks gestation.

The aim of this study was to develop an accurate formula for the ultrasonic prediction of fetal weight for infants < 33 weeks gestational age and < or = 1500 g birthweight. The subjects comprised live births free of lethal malformations or chromosomal anomalies, < 33 weeks gestational age and with birthweights +/- 1500 g born in the Royal Women's Hospital between January 1990 and March 1996. All subjects had accurate gestational age confirmed by ultrasound prior to 20 weeks gestation and ultrasound measurements within 72 hours of birth of biparietal diameter (BPD), femur length (FL) and abdominal circumference (AC). A formula with the highest explained variance was computed by linear regression analysis using the three fetal variables in various combinations from 54 infants born between January 1990 and December 1993. The optimal formula was: Log(10)birthweight = 0.714627 + 0.077362.AC + 0.058758.BPD + 0.287037.FL - 0.011274.AC.FL. The new formula was more accurate compared with existing formulae when tested in a separate cohort of 39 infants born between January 1994 and March 1996.

Prognosis of congenital diaphragmatic hernia.

Congenital diaphragmatic hernia (CDH) contributes significantly to perinatal morbidity and mortality. This retrospective study examines the experience of a major teaching hospital to establish survival rates and factors influencing outcome. Survival rates were found to relate closely to the stage at which the diagnosis was made and the presence of associated anomalies. Ultrasound diagnosis early in pregnancy is associated with a higher mortality rate than diagnosis made late in pregnancy or after delivery. Logistic regression analysis and chi-squared analysis did not establish to a significant degree that any factor, alone or in combination, was a reliable prognostic indicator. It is acknowledged, however, that figures in this series are small. Survival figures are presented to facilitate reliable parental counselling. In particular, the presence of associated major anomalies and the gestational age at which diagnosis is made are of critical importance in accurately counselling parents regarding the prognosis for survival. In this study, excluding terminations, the mortality rate for isolated CDH diagnosis before the 21st week was 45.5%, with a corresponding survival rate of 54.5%. Once the infant was liveborn, however, the survival rate rose to 68.0%, and if the infant survived transfer to a paediatric surgical unit, the survival rate in this study was 73.9 %.

The effect of epidural bupivacaine on the fetal electrocardiogram.

Fetal electrocardiogram waveform analysis was used to assess the effect of epidural bupivacaine on the fetal myocardial conducting system by evaluating its effect on the PR interval, RR interval, T/QRS ratio and the PR-RR correlation coefficient. There were no significant changes in either the PR interval or the PR-RR correlation coefficient. There was a significant increase in the fetal heart rate and a significant fall in the T/QRS ratio. Epidural bupivacaine does not alter fetal myocardial conduction as measured by the PR interval and it does not induce ischaemic cardiac changes as assessed by the T/QRS ratio.

Intrapartum cardiotocography and the expert witness.

Fetal heart rate changes occur in the majority of labours and correlate poorly with perinatal outcome and subsequent neurological development. Obstetricians giving expert evidence related to the interpretation of intrapartum cardiotocographs are advised to exercise caution when expressing their opinions.

Pseudosinusoidal fetal heart rate pattern and fetal anaemia: case report and review.

The association of a pseudosinusoidal fetal heart rate pattern with fetal anaemia is reported. A system of classifying this cardiotocographic feature as minor, intermediate or major is discussed. The clinical correlates of each of these gradings and the differentiation from a true sinusoidal fetal heart rate pattern are presented.

Epidural analgesia and fetal heart rate abnormalities.

Lumbar epidural analgesia is frequently associated with fetal heart rate abnormalities. Fluid preloading prior to the procedure significantly reduces the incidence of abnormal fetal heart rate patterns (p = 0.02). The mechanisms of these changes are discussed and the importance of maternal hypotension is evaluated. Fluid preloading and continuous electronic fetal monitoring should be considered routine for all women undergoing this procedure.

The predictive value of abnormal fetal heart rate patterns in early labour.

An abnormal early intrapartum cardiotocogram was found to have a sensitivity of 26.4% and a positive predictive value of 28.3% for the detection of fetal acidaemia at birth and a sensitivity of 27.3% and a positive predictive value of 3.3% for the prediction of 5-minute Apgar scores below 7. The presence of meconium in the liquor amnii improved the predictive properties of the test. Although an abnormal early intrapartum feta heart rate pattern indicated a higher risk group, the majority of patients with abnormal early intrapartum cardiograms had a favourable outcome. A normal pattern does not exclude an adverse outcome.

Headache following epidural analgesia.

Many headaches following epidural analgesia are a consequence of a dural tap having occurred. However, this is not always the case and careful evaluation is required. A case of postpartum headache caused by an intracerebral haemorrhage is presented.

Urodynamic investigation in the management of incontinent women.

One hundred and sixty-eight women presenting to a Urinary Incontinence Clinic were studied. Only 52% had a urodynamic diagnosis that supported their clinical signs and symptoms. The response rates to various modalities of treatment for each urinary disorder are described. Fifty-one percent achieved a complete response with the treatment selected, 27% had a partial response, and 10% did not respond or deteriorated. Twelve percent of patients were lost to follow-up.

Presacral neurectomy--a reappraisal.

Between April 1984 and April 1990, 20 patients with a mean age of 27.9 years underwent presacral neurectomy at The Royal Women's Hospital, Melbourne, Australia. Overall, 11 of the 19 patients (58%) assessable for follow-up were totally cured of pain and 8 (42%) were partially cured. The most common indication for presacral neurectomy was secondary dysmenorrhoea, usually in association with endometriosis or pelvic adhesions. In 4 patients with uterine dysmenorrhoea not associated with pelvic pathology the operation produced a complete cure. The general consensus of gynaecological opinion is that presacral neurectomy should still be reserved for a limited number of carefully selected patients in whom other methods of treatment have been exhausted. It is imperative that a prior psychological assessment should be undertaken whenever a functional component is suspected. Whilst pain of uterine origin may be cured by presacral neurectomy, lateral pelvic pain of adnexal origin requires ovarian sympathectomy.

Transabdominal chorionic villus sampling.

The first 100 patients undergoing first trimester transabdominal chorionic villus sampling (placental biopsy) in our hospital are reviewed. At the time of follow up 24 patients had delivered, 68 pregnancies were at 24 weeks or more and progressing normally, 7 pregnancies were terminated and there was only 1 spontaneous miscarriage. The advantages of the transabdominal approach are discussed.