Andre Francis

Perinatal outcome in SGA births defined by customised versus population-based birthweight standards

Objective To determine whether customised birthweight standard improves the definition of small for gestational age and its association with adverse pregnancy outcomes such as stillbirth, neonatal death, or low Apgar score.

Classification of stillbirth by relevant condition at death (ReCoDe): population based cohort study

Abstract Objective To develop and test a new classification system for stillbirths to help improve understanding of the main causes and conditions associated with fetal death. Design Population based cohort study. Setting West Midlands region. Subjects 2625 stillbirths from 1997 to 2003. Main outcome measures Categories of death according to conventional classification methods and a newly developed system (ReCoDe, relevant condition at death). Results By the conventional Wigglesworth classification, 66.2% of the stillbirths (1738 of 2625) were unexplained. The median gestational age of the unexplained group was 237 days, significantly higher than the stillbirths in the other categories (210 days; P < 0.001). The proportion of stillbirths that were unexplained was high regardless of whether a postmortem examination had been carried out or not (67% and 65%; P = 0.3). By the ReCoDe classification, the most common condition was fetal growth restriction (43.0%), and only 15.2% of stillbirths remained unexplained. ReCoDe identified 57.7% of the Wigglesworth unexplained stillbirths as growth restricted. The size of the category for intrapartum asphyxia was reduced from 11.7% (Wigglesworth) to 3.4% (ReCoDe). Conclusion The new ReCoDe classification system reduces the predominance of stillbirths currently categorised as unexplained. Fetal growth restriction is a common antecedent of stillbirth, but its high prevalence is hidden by current classification systems. This finding has profound implications for maternity services, and raises the question whether some hitherto “unexplained” stillbirths may be avoidable.

Maternal and fetal risk factors for stillbirth: population based study

Objective To assess the main risk factors associated with stillbirth in a multiethnic English maternity population. Design Cohort study. Setting National Health Service region in England. Population 92 218 normally formed singletons including 389 stillbirths from 24 weeks of gestation, delivered during 2009-11. Main outcome measure Risk of stillbirth. Results Multivariable analysis identified a significant risk of stillbirth for parity (para 0 and para ≥3), ethnicity (African, African-Caribbean, Indian, and Pakistani), maternal obesity (body mass index ≥30), smoking, pre-existing diabetes, and history of mental health problems, antepartum haemorrhage, and fetal growth restriction (birth weight below 10th customised birthweight centile). As potentially modifiable risk factors, maternal obesity, smoking in pregnancy, and fetal growth restriction together accounted for 56.1% of the stillbirths. Presence of fetal growth restriction constituted the highest risk, and this applied to pregnancies where mothers did not smoke (adjusted relative risk 7.8, 95% confidence interval 6.6 to 10.9), did smoke (5.7, 3.6 to 10.9), and were exposed to passive smoke only (10.0, 6.6 to 15.8). Fetal growth restriction also had the largest population attributable risk for stillbirth and was fivefold greater if it was not detected antenatally than when it was (32.0% v 6.2%). In total, 195 of the 389 stillbirths in this cohort had fetal growth restriction, but in 160 (82%) it had not been detected antenatally. Antenatal recognition of fetal growth restriction resulted in delivery 10 days earlier than when it was not detected: median 270 (interquartile range 261-279) days v 280 (interquartile range 273-287) days. The overall stillbirth rate (per 1000 births) was 4.2, but only 2.4 in pregnancies without fetal growth restriction, increasing to 9.7 with antenatally detected fetal growth restriction and 19.8 when it was not detected. Conclusion Most normally formed singleton stillbirths are potentially avoidable. The single largest risk factor is unrecognised fetal growth restriction, and preventive strategies need to focus on improving antenatal detection.

Restricted fetal growth in sudden intrauterine unexplained death

Background.  Unexplained antepartum stillbirth is a common cause of perinatal death, and identifying the fetus at risk is a challenge for obstetric practice. Intrauterine growth restriction (IUGR) is associated with a variety of adverse perinatal outcomes, but reports on its impact on unexplained stillbirths by population‐based birthweight standards have been varying, including both unexplained and unexplored stillbirths.

Adverse pregnancy outcome and association with small for gestational age birthweight by customized and population-based percentiles

OBJECTIVE The objective of the study was to investigate the association between pregnancy complications and small for gestational age (SGA) birthweight, comparing SGA based on the customized growth potential with SGA based on the birthweight standard of the same population. STUDY DESIGN This was a retrospective analysis of a database from a US multicenter study. Pregnancy complications included threatened preterm labor, antepartum hemorrhage, pregnancy-induced hypertension, preeclampsia, stillbirth, and early neonatal death. RESULTS Compared with SGA by the birthweight standard, SGA by customized growth potential showed higher risk for each of the 6 adverse indicators. A third of the SGA group was small by customized centiles but not by population-based centiles, yet was strongly associated with each of the pregnancy complications studied. This subgroup of unrecognized SGA babies included 26% preterm deliveries. In contrast, a subgroup that was SGA by the population standard but not by the customized standard (17.2%), was not associated with any of the indicators of adverse outcome. CONCLUSION SGA defined by customized growth potential improves the differentiation between physiologically and pathologically small babies.

A customised birthweight centile calculator developed for a New Zealand population.

Background:  Traditionally, small for gestational age is defined as birthweight <10th percentile using sex‐adjusted centile charts. However, this criterion includes constitutional variation due to maternal height, weight, ethnic group and parity.

Controlled trial of fundal height measurement plotted on customised antenatal growth charts

Objective The purpose of this study was to evaluate the effect of a policy of standard antenatal care which included plotting fundal height measurements on customised antenatal charts in the community.

Cerebral palsy and restricted growth status at birth: population-based case-control study

Objective  To evaluate the association between growth status at birth and subsequent development of cerebral palsy in preterm and term infants.

A customized standard to assess fetal growth in a US population

OBJECTIVE The objective of the study was to assess the factors that affect fetal growth and birthweight, and to derive coefficients for a customized growth chart applicable in an American population. STUDY DESIGN This was a prospective cohort study of 35,235 pregnancies. Coefficients for physiological and pathological variables were derived by backward multiple regression. RESULTS The expected birthweight at 40.0 weeks for a standard-size primiparous mother of European origin in an uncomplicated pregnancy was 3453.4 g, very similar to the standardized birthweight observed in other populations. Physiological coefficients were derived for maternal height, weight, parity, ethnic origin, and sex of the baby. Smoking, history of preterm delivery, and hypertensive diseases in the current pregnancy all had negative effects on birthweight, whereas babies of diabetic mothers weighed more. Low as well as high body mass index was associated with birthweight deficit at term. CONCLUSION Coefficients that allow determination of the customized growth potential, individually adjusted and excluding known pathological factors, have been derived. Babies of obese mothers have an increased risk of not reaching their fetal growth potential.

The value of customised centiles in assessing perinatal mortality risk associated with parity and maternal size.

Objective  We wanted to compare customised and population standards for defining smallness for gestational age (SGA) in the assessment of perinatal mortality risk associated with parity and maternal size.