Angiogenic factors combined with clinical risk factors to predict preterm pre-eclampsia in nulliparous women: a predictive test accuracy study.

OBJECTIVES: To assess the performance of clinical risk factors, uterine artery Doppler and angiogenic markers to predict preterm pre-eclampsia in nulliparous women. DESIGN: Predictive test accuracy study. SETTING: Prospective multicentre cohort study Screening for Pregnancy Endpoints (SCOPE). METHODS: Low-risk nulliparous women with a singleton pregnancy were recruited. Clinical risk factor data were obtained and plasma placental growth factor (PlGF), soluble endoglin and soluble fms-like tyrosine kinase-1 (sFlt-1) were measured at 14-16 weeks of gestation. Prediction models were developed using multivariable stepwise logistic regression. MAIN OUTCOME MEASURE: Preterm pre-eclampsia (delivered before 37(+0)  weeks of gestation). RESULTS: Of the 3529 women recruited, 187 (5.3%) developed pre-eclampsia of whom 47 (1.3%) delivered preterm. Controls (n = 188) were randomly selected from women without preterm pre-eclampsia and included women who developed other pregnancy complications. An area under a receiver operating characteristic curve (AUC) of 0.76 (95% CI 0.67-0.84) was observed using previously reported clinical risk variables. The AUC improved following the addition of PlGF measured at 14-16 weeks (0.84; 95% CI 0.77-0.91), but no further improvement was observed with the addition of uterine artery Doppler or the other angiogenic markers. A sensitivity of 45% (95% CI 0.31-0.59) (5% false-positive rate) and post-test probability of 11% (95% CI 9-13) were observed using clinical risk variables and PlGF measurement. CONCLUSIONS: Addition of plasma PlGF at 14-16 weeks of gestation to clinical risk assessment improved the identification of nulliparous women at increased risk of developing preterm pre-eclampsia, but the performance is not sufficient to warrant introduction as a clinical screening test. These findings are marker dependent, not assay dependent; additional markers are needed to achieve clinical utility.

The impact of maternal body mass index on the phenotype of pre-eclampsia: a prospective cohort study.

OBJECTIVE: We hypothesised that among nulliparous women with pre-eclampsia, overweight or obese women would have a different phenotype of pre-eclampsia compared with normal weight women with pre-eclampsia. Specifically, they are more likely to develop term pre-eclampsia and less likely to have indicators of impaired placental perfusion, e.g. abnormal uterine artery Doppler or a small-for-gestational-age (SGA) infant. DESIGN: Prospective, multicentre, cohort SCOPE study (n = 3170). SETTING: New Zealand and Australia. POPULATION: Nulliparous women who developed pre-eclampsia. METHODS: Participants were interviewed at 14-16 weeks of gestation, uterine artery Doppler studies were performed at 19-21 weeks and pregnancy outcome was tracked prospectively. MAIN OUTCOME MEASURES: Rates of abnormal uterine artery Doppler indices, term/preterm birth and SGA infants were compared between normal, overweight and obese women with pre-eclampsia. Multivariable analysis was performed to examine the association between body mass index (BMI) and term pre-eclampsia. RESULTS: Of 178 women with pre-eclampsia, one underweight woman was excluded and 66 (37%) were normal weight, 52 (29%) were overweight and 59 (34%) were obese. Pre-eclampsia developed preterm in 26% of women and at term in 74% of women. There were no differences in the rates of term/preterm pre-eclampsia, abnormal uterine artery Doppler indices or SGA infants between BMI groups (P > 0.10). No independent association between BMI and term pre-eclampsia was found (P = 0.56). CONCLUSIONS: Among women with pre-eclampsia, those who are overweight or obese in early pregnancy are not more likely to have term pre-eclampsia compared with women with a normal BMI. Overweight and obese women require vigilant surveillance for the development of preterm as well as term pre-eclampsia.

Risk factors for small-for-gestational-age infants by customised birthweight centiles: data from an international prospective cohort study.

OBJECTIVE: To identify clinical and ultrasound variables associated with the birth of small-for-gestational-age (SGA) infants by customised centiles, subclassified according to whether their mothers were normotensive or developed hypertensive complications. DESIGN: Prospective, multicentre cohort study. SETTING: Participating centres of the Screening for Pregnancy Endpoints (SCOPE) study in Auckland, New Zealand, Adelaide, Australia, Manchester and London, UK, and Cork, Ireland. POPULATION: The 3513 nulliparous participants of the SCOPE study. METHODS: Women were interviewed at 15 ± 1 weeks, and had ultrasound growth measurements and umbilical and uterine Doppler studies at 20 ± 1 weeks. Variables associated with SGA infants were identified using logistic regression. MAIN OUTCOME MEASURES: Small for gestational age (i.e. a birthweight of less than the tenth customised centile), normotensive-SGA and hypertensive-SGA. Comparison groups for statistical analyses were non-SGA, normotensive non-SGA and hypertensive non-SGA. RESULTS: Among 376 (10.7%) SGA infants, 281 (74.7%) were normotensive-SGA and 95 (25.3%) were hypertensive-SGA. Independent risk factors for normotensive-SGA were low maternal birthweight, low fruit intake pre-pregnancy, cigarette smoking, increasing maternal age, daily vigorous exercise, being a tertiary student, head and abdominal circumference of less than the tenth centile and increasing uterine artery Doppler indices at the 20-week scan. Protective factors were: high green leafy vegetable intake pre-pregnancy, and rhesus-negative blood group. Risk factors for hypertensive-SGA were conception by in vitro fertilisation, previous early pregnancy loss and femur length of less than tenth centile at the 20-week scan. CONCLUSIONS: Risk factors for infants who are SGA by customised centiles have been identified in a cohort of healthy nulliparous women. A number of these factors are modifiable; however, further studies are needed to replicate these findings.

The effect of 10 degrees head-up tilt in the right lateral position on the systemic blood pressure after subarachnoid block for Caesarean section.

Forty women presenting for elective Caesarean section under spinal anaesthesia were randomly assigned to have anaesthesia induced in the right lateral position either in the horizontal position or with 10 degrees head-up tilt. Hyperbaric bupivacaine 2 ml 0.5% with 0.1 mg of morphine was injected intrathecally before the parturients were placed in the supine position with 15 degrees left lateral tilt. Blood pressure and heart rate were monitored every minute and the sensory level (loss of sharp sensation to pinprick) was monitored every 3 min until clamping of the umbilical cord. Ephedrine 6 mg was given every minute that the systolic blood pressure decreased below 90 mmHg. The mean systolic blood pressure during the first 5 min after induction of spinal anaesthesia was lower in the control group compared to the tilted group (99 mmHg vs. 109 mmHg; p = 0.043). The upper limit of block was higher in the control group compared to the tilted group (p = 0.002). The use of 10 degrees head-up tilt resulted in a reduced incidence of hypotension initially and less extensive sensory block.