Making small risks even smaller

Risk of stillbirth and infant death stratified by gestational age

OBJECTIVE

To estimate the multiple dimensions of risk faced by pregnant women and their health care providers when comparing the risks of stillbirth at term with the risk of infant death after birth.

METHODS

This is a retrospective cohort study that included all nonanomalous, term deliveries in the state of California from 1997 to 2006 (N=3,820,826). The study compared infant mortality rates after delivery at each week of term pregnancy with the rates of a composite fetal-infant mortality that would occur after expectant management for 1 additional week.

RESULTS

The risk of stillbirth at term increases with gestational age from 2.1 per 10,000 ongoing pregnancies at 37 weeks of gestation up to 10.8 per 10,000 ongoing pregnancies at 42 weeks of gestation. At 38 weeks of gestation, the risk of expectant management carries a similar risk of death as delivery, but at each later gestational age, the mortality risk of expectant management is higher than the risk of delivery (39 weeks of gestation: 12.9 compared with 8.8 per 10,000; 40 weeks of gestation: 14.9 compared with 9.5 per 10,000; 41 weeks of gestation: 17.6 compared with 10.8 per 10,000).

CONCLUSION

Infant mortality rates at 39, 40, and 41 weeks of gestation are lower than the overall mortality risk of expectant management for 1 week.

Late preterm birth: preventable prematurity?

Prematurity is one of the leading causes of infant morbidity and mortality globally. Over the years, however, advances in medicine and technology have enhanced the ability to care for babies at very early gestations. There has also been a shift in the distribution of births away from term/post-term gestations and toward earlier gestational ages. These changes have added to the burden of premature births. The focus of this article is to present both sides of the story, one that highlights the many problems and morbidities faced by this subgroup of premature infants and the other that justifies their early delivery.

Term pregnancy: time for a redefinition

The designation term pregnancy and the distinction between term, preterm, and postterm pregnancy carry with them significant clinical implications with respect to the management of pregnancy complications. Although the potential hazards of both preterm birth and postterm pregnancy have been long recognized, little attention has, until recently, been given to the differential morbidity experienced by neonates born at different times within the 5-week interval classically considered term gestation. This article is a reevaluation of the concept of term pregnancy in light of current data.

What's new in obstetric anesthesia?

The current article covers some of the major themes that emerged in 2009 in the fields of obstetric anesthesiology, obstetrics, and perinatology, with a special emphasis on the implications for the obstetric anesthesiologist.

Reduction in elective delivery at <39 weeks of gestation: comparative effectiveness of 3 approaches to change and the impact on neonatal intensive care admission and stillbirth

OBJECTIVE

No studies exist that have examined the effectiveness of different approaches to a reduction in elective early term deliveries or the effect of such policies on newborn intensive care admissions and stillbirth rates.

STUDY DESIGN

We conducted a retrospective cohort study of prospectively collected data and examined outcomes in 27 hospitals before and after implementation of 1 of 3 strategies for the reduction of elective early term deliveries.

RESULTS

Elective early term delivery was reduced from 9.6-4.3% of deliveries, and the rate of term neonatal intensive care admissions fell by 16%. We observed no increase in still births. The greatest improvement was seen when elective deliveries at <39 weeks were not allowed by hospital personnel.

CONCLUSION

Physician education and the adoption of policies backed only by peer review are less effective than "hard stop" hospital policies to prevent this practice. A 5% rate of elective early term delivery would be reasonable as a national quality benchmark.

Birth after previous cesarean delivery: short-term maternal outcomes

An estimated 40% of the 1.3 million cesarean deliveries performed each year in the United States are repeat procedures. The appropriate clinical management approach for women with previous cesarean delivery remains challenging because options are limited. The risks and benefits of clinical management choices in the woman's health need to be quantified. Thus, we discuss the available published scientific data on (1) the short-term maternal outcomes of trial of labor after cesarean and elective repeat cesarean delivery, (2) the differences between outcomes for both, (3) the important factors that influence these outcomes, and (4) successful vs. unsuccessful vaginal birth after cesarean. For women with a previous cesarean delivery, a successful trial of labor offers several distinct, consistently reproducible advantages compared with elective repeat cesarean delivery, including fewer hysterectomies, fewer thromboembolic events, lower blood transfusion rates, and shorter hospital stay. However, when trial of labor after cesarean fails, emergency cesarean is associated with increased uterine rupture, hysterectomy, operative injury, blood transfusion, endometritis, and longer hospital stay. Care of women with a history of previous cesarean delivery involves a confluence of interactions between medical and nonmedical factors; however, the most important determinants of the short-term outcomes among these women are likely individualized counseling, accurate clinical diagnoses, and careful management during a trial of labor. We recommend a randomized controlled trial among women undergoing a TOLAC and a longitudinal cohort study among women with previous cesarean to evaluate adverse outcomes, with focused attention on both mother and the infant.

Neonatal Outcomes in Relation to Timing of Repeat Cesarean Delivery at Term

Evaluation of: Tita AT, Landon MB, Spong CY et al.: Timing of elective repeat cesarean delivery at term and neonatal outcomes. N. Engl. J. Med. 360(2), 111–120 (2009). The increasing rates of repeat cesarean delivery necessitate, more than ever, the need to time deliveries to optimize neonatal outcomes. A recent large multicenter cohort study demonstrated that, contrary to current recommendations, a high proportion of elective cesarean deliveries in the USA are performed before 39 weeks' gestation. These early deliveries are associated with a significant increase in several adverse neonatal events, including respiratory complications, treated hypoglycemia, newborn sepsis and admission to the neonatal intensive care unit. This, together with results of previous studies, supports the recommendation to delay elective delivery to 39 weeks' gestation. From the current data, it is uncertain whether delivery before 39 weeks' gestation with documented fetal lung maturity will prevent the increased neonatal morbidity.