Jan E. Dickinson

Outcomes of Congenital Diaphragmatic Hernia: A Population-Based Study in Western Australia

Objectives. There have been many recent reports of improved survival rates for congenital diaphragmatic hernia (CDH), largely derived from institution-based data. These are often flawed by case selection bias. The objectives of this study were to document the true incidence, management, and outcomes of CDH in a geographically defined population over a 12-year period and to determine the changing trends in these over time. We also sought to ascertain the prenatal and postnatal factors associated with morbidity and death among these infants. Methods. A retrospective study of all cases of CDH in Western Australia from 1991 to 2002 was conducted. Cases were identified from 5 independent databases within the Western Australian health network, including the Western Australian Birth Defects Registry. All fetuses and neonates diagnosed with CDH in Western Australia during this period were identified, including miscarriages, stillbirths, and terminations of pregnancies in which a diagnosis of fetal CDH had been made, as well as those diagnosed postnatally. Cases not known to involve CDH until diagnosis at autopsy were also included. Infants with diaphragmatic eventration were excluded from the study. Detailed information was obtained from review of maternal and infant medical records. Results. One hundred sixteen cases of CDH were identified. Of these, 71 (61%) infants were born alive and 37 survived beyond 1 year of age (52% of live-born infants, 32% of all cases of CDH). Pregnancies involving 38 (33%) fetuses were terminated electively, 4 (3%) fetuses were aborted spontaneously, and 3 (3%) fetuses were stillborn. Another major congenital anomaly was present in 54 (47%) cases. Twenty-one (18%) cases had other anomalies that were likely to be fatal. Of all cases with an additional major anomaly, 42 (78%) died. Twenty-seven (71%) of 38 fetuses for whom the pregnancy was terminated had another major anomaly. Twenty-three (32%) live-born infants had another major anomaly (4 of which were considered fatal conditions); however, this did not affect their survival rates. Fifty-three percent of cases were diagnosed prenatally, and 49% of these pregnancies were then terminated. Of live-born infants with prenatally diagnosed CDH, 10 (33%) survived beyond 1 year of age. The gestational age at diagnosis did not affect the survival rate for live-born infants. Postnatal diagnosis occurred in 55 (47%) cases. Of these, 41 (74%) case subjects were born alive and diagnosed on clinical grounds after birth. In the remaining 14 cases, the diagnosis was made in postmortem examinations of fetuses from pregnancies that were terminated for other reasons (8 cases) or after spontaneous abortion or stillbirth (5 cases). Significant differences were found between prenatally and postnatally diagnosed live-born infants. Among live-born infants, prenatal diagnosis was associated with a significantly reduced survival rate (33%, compared with 66% for postnatally diagnosed infants). Prenatally diagnosed live-born infants were of lower birth weight and were born at an earlier gestational age. There was no statistically significant difference between the 2 groups in the onset of labor (spontaneous or induced) or in the rate of elective cesarean sections. Prenatally diagnosed live-born infants were more likely to be delivered in a tertiary perinatal center and were intubated more commonly at delivery. No difference was found in the Apgar scores at either 1 or 5 minutes between the groups. Of 71 live-born infants, 37 (52%) survived to 1 year of age. The majority of deaths occurred within the first 7 days of life (44%). Preoperative air leaks occurred for 16 (22%) infants, of whom 14 (88%) died. Factors found to predict death of live-born infants included prenatal diagnosis, right-sided hernia, major air leak, earlier gestational age at birth, lower birth weight, and lower Apgar scores at 1 and 5 minutes. Over the course of the decade, there were significant increases in the proportion of cases in which the diagnosis of CDH was made with prenatal ultrasonography and in the number of live-born infants born at the tertiary perinatal center. The mortality rate for all cases, the mortality rate for live-born infants, and the proportion of pregnancies involving prenatally diagnosed cases that were terminated electively were all greater in the later epoch but not significantly so. Conclusions. This was a comprehensive, population-based study of CDH, with full case ascertainment, large sample size, and complete outcome data for all cases. The majority of published studies of CDH examined specific patient populations, such as neonates referred to tertiary pediatric surgical centers. Invariably, those studies failed to detect the demise of cases with CDH before arrival at the referral center, whether through termination of pregnancy, in utero fetal demise, or postnatal death occurring before transfer. Exclusion of these cases from calculations of mortality rates results in significant case selection bias. In our study, 35% of live-born infants died before referral or transport. The population of infants reaching the tertiary surgical center represented only 40% of the total cases of CDH. Wide variations in reported survival rates occur throughout the literature. These differences reflect the influence of this case selection bias, as well as variable referral policies and management practices. For our study population, survival rates differed vastly depending on the subgroup analyzed. Ninety-two percent of postoperative infants survived beyond 1 year of age, as did 80% of infants who reached the surgical referral center. However, only 52% of live-born infants, 32% of all cases, and 16% of all prenatally diagnosed cases survived. Therefore, the overall mortality rate for this condition remains high, despite increased prenatal detection, transfer to tertiary institutions for delivery, and advances in neonatal care, and is influenced significantly by the rate of prenatal termination. In our study, 33% of all cases of CDH and 49% of prenatally diagnosed fetuses underwent elective termination of pregnancy. This large number of fetal terminations confounds the accurate assessment of the true outcomes of this condition.

Induction of labour in nulliparous women with an unfavourable cervix: a randomised controlled trial comparing double and single balloon catheters and PGE2 gel.

Objective  To compare the efficacy and patient satisfaction of three methods of labour induction (double balloon catheters, single balloon catheters and prostaglandin gel) in term nulliparous women with unfavourable cervices.

The epidemiologic incidence of congenital gastroschisis in Western Australia

OBJECTIVE The purpose of this study was to review the population incidence of congenital gastroschisis in Western Australia over the past 2 decades. STUDY DESIGN A population-based incidence study of congenital gastroschisis from 1980 to 2001. Maternal and perinatal outcome data were collected to ascertain incidence, treatment, and outcome trends. RESULTS One hundred twenty-two cases of gastroschisis were identified. The median maternal age was 23 years (range, 16-35 years). Women aged <20 years were at a 7.82 increased risk (95% CI, 4.34-14.08); women aged 20 to 24 years were at a 3.24 increased risk (95% CI, 1.88-5.61) for fetal gastroschisis compared with women aged >or=25 years. An incidence analysis over time indicated a significant increase of gastroschisis cases from 1 of 10,000 births during the period 1980-1990 to the current rate of 2.4 of 10,000 births (P<.001). The perinatal mortality rate was 12.7% (95% CI, 8.7-16.7) with a 9.8% stillbirth rate (95% CI, 6.3-13.3). CONCLUSION There has been a sustained increase in the birth incidence of gastroschisis over the past decade, particularly in teenage women. A significant fetal death rate in the third trimester is observed.

Misoprostol for second-trimester pregnancy termination in women with a prior cesarean delivery

OBJECTIVE: To evaluate the use of misoprostol in second-trimester abortion in women with prior cesarean deliveries. METHODS: A review of women with prior cesarean deliveries undergoing abortion at 14–28 weeks of gestation for a fetal anomaly over a 7.5-year period. Outcome data were compared with a contemporaneous cohort of women with unscarred uteri undergoing the same procedure. Misoprostol was used to induce abortion in all cases, and a variety of dosage regimens were used, the most frequent being 400 μg vaginally every 6 hours (71.3%). RESULTS: During the study period, 720 consecutive women underwent a second-trimester abortion for a fetal anomaly using misoprostol. One hundred one women (14%) had at least 1 prior cesarean delivery: 78 women had 1, 19 women had 2, and 4 women had 3 prior cesarean deliveries. Women with a prior cesarean birth were significantly older (30 years [interquartile range 26–35] versus 33 years [29–37], no cesarean delivery versus cesarean delivery, P = < .001) and of increased parity. The median gestational age at delivery was 19.4 weeks (interquartile range 18–20.7) versus 19.3 weeks (17.7–21), no cesarean delivery versus cesarean delivery, P = .48. The presence of a prior uterine scar did not impact upon abortion duration (16.6 hours [12.1–23.8] versus 14.5 hours [11.4–21.4], no cesarean delivery versus cesarean delivery, P = .07). No differences in blood loss, major hemorrhage, or blood transfusion occurred. There was no case of uterine rupture or hysterectomy. CONCLUSION: In second-trimester abortion, the use of misoprostol in women with prior cesarean delivery was not associated with an excess of complications compared with women with unscarred uteri. LEVEL OF EVIDENCE: II-2

Serum antimullerian hormone (AMH) levels are elevated in adolescent girls with polycystic ovaries and the polycystic ovarian syndrome (PCOS)

Polycystic ovarian syndrome (PCOS) is a common endocrine disorder in adolescents, with potentially significant lifelong consequences. This prospective study set out to determine if the investigators could derive a threshold value of antimullerian hormone (AMH) that would predict its presence according to two internationally recognized definitions using a simple measurement, avoiding more extensive and potentially more invasive investigations. The study failed to demonstrate, in a general adolescent population, that serum AMH is a reliable predictor of PCO morphology or for the presence of PCOS.

Efficacy of Intravaginal Misoprostol in Second-Trimester Pregnancy Termination: A Randomized Controlled Trial

A prospective randomized, double-blind, controlled clinical trial to compare the clinical efficacy and side effects of intravaginal misoprostol with the traditional prostaglandin, gemeprost, in second-trimester pregnancy interruption was conducted. A sample size of 100 women was calculated to demonstrate that misoprostol was as effective as gemeprost in achieving delivery within 24 hours (alpha = 0.1, 80% power). Women were recruited with fetal death in utero, severe fetal anomaly, or psychosocial pregnancy termination between 14 and 28 weeks gestation and randomized to receive either 1 mg gemeprost 3 hourly for 5 doses, or 200 mcg misoprostol 6 hourly for 4 doses, intravaginally. The therapeutic regimens were repeated if undelivered by 24 hours. Those undelivered after 48 hours received an extra-amniotic PGF2 alpha infusion. The median gestation at recruitment was identical: gemeprost 19 weeks (IQ 17-22 weeks) vs. misoprostol 19 weeks (IQ 17-21 weeks), P = 0.887. Delivery within 24 hours occurred in 75.1% of women receiving gemeprost and 74.9% receiving misoprostol (P = 1.0). The median time from prostaglandin commencement to delivery was similar: gemeprost 13.7 hours (IQ 9.0-23.5 hours) vs. misoprostol 16.9 hours (IQ 10.3-23.5 hours), P = 0.769. A significant reduction in the incidence of vomiting in women randomized to misoprostol occurred (34% vs. 13.2%, P = 0.017). There was no significant difference in the incidence of maternal fever > 37.5 degrees C, nausea, diarrhea, or placental retention. A 200-fold pharmaceutical cost advantage was observed with the use of misoprostol compared with gemeprost. Intravaginal misoprostol performs as effectively as gemeprost in achieving delivery in the second trimester without increase in adverse effects and displaying a significant cost advantage.

Caesarean scar ectopic pregnancy: A single centre case series

Objective:  To examine the characteristics, management and outcomes of 13 caesarean scar pregnancies (CSPs) at a single tertiary obstetric centre over a five‐year period.

Impact of intrapartum epidural analgesia on breast-feeding duration

Background:  Although the labour and delivery outcomes of epidural analgesia have been investigated extensively, the effects on breast‐feeding success are not clearly identified.

Socio-demographic disparities in the uptake of prenatal screening and diagnosis in Western Australia.

Introduction:  Since the early 1980s, prenatal screening using ultrasound and biochemical markers has been used to refine the risk of Down syndrome and other fetal anomalies prior to considering fetal karyotyping. The performance of prenatal screening is subject to ongoing monitoring in Western Australia. The collection of these data can also assist in the identification of any potential inequities of access to prenatal screening within the state‐wide programme.

First-trimester combined screening for Down syndrome and other fetal anomalies.

OBJECTIVE: This study assessed fetal outcomes for pregnancies identified at increased risk for Down syndrome by first-trimester combined ultrasound examination and maternal serum biochemistry screening. METHODS: First-trimester combined screening data were obtained from ultrasound clinics across Western Australia between August 2001 and October 2003. Prenatal screening data were linked with pregnancy outcome information held in state health database registers using probabilistic record-linkage techniques. RESULTS: In 50 of the 60 pregnancies affected by Down syndrome, the adjusted risk was greater than 1 in 300, providing a detection rate of 83% (95% confidence interval [CI] 74–93%). Among all women screened (n = 22,280), 827 had increased risk results but did not have a Down syndrome pregnancy, representing a false-positive rate of 3.7% (95% CI 3.5–3.9%). Ten cases of Down syndrome were detected among women considered not at increased risk, consistent with a false-negative rate of 1 in 2,227. First-trimester combined screening reduced the number of Down syndrome births by 50 in 22,280 (2.24 cases per 1,000 births), which represents the detection of one case of fetal Down syndrome for every 446 women screened. Furthermore, 25% of pregnancies with other birth defects occurred among those identified at increased risk of Down syndrome, and 1 in 8 pregnancies at increased risk were found to have a significant chromosomal or structural defect. CONCLUSION: First-trimester combined screening in Western Australia detected 83% (95% CI 74–93%) of Down syndrome pregnancies at a 3.7% (95% CI 3.5–3.9%) false-positive rate. LEVEL OF EVIDENCE: II-2