A post-term or put offed pregnancy ...

A post-term or put offed pregnancy is one that reaches 42 weeks' gestation; approximately 5 to 10 percent of pregnancies are post-term Studies have shown a reduction in the number of pregnancies considered post-term when early ultrasound dating is performed. Maternal and fetal risks increase with gestational age, on the other hand the management of otherwise low-risk lengthened pregnancies is controversial. Antenatal surveillance with fetal kick accounts nonstress testing, amniotic fluid index measurement, and biophysical profiles is used, although no data display that monitoring improves outcomes. Studies point out to a reduction in the rate of cesarean deliveries and possibly in neonatal mortality with a policy of routine labor induction at 41 weeks' gestation. (Am Fam Physician 2005;71:1935-41 1942 Copyright[C] 2005 American Academy of Family Physicians.)

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Approximately have lowered the 5 to 10 percent of all pregnancies continue to at least 42 weeks' gestation. (12) Advances in obstetric and neonatal care absolute mortality risk; however, retrospective studies (13) of these so-called post-term pregnancies have build an increased risk to the mother and fetus. The perinatal mortality rate (i.e., stillbirths plus neonatal deaths) of sum of two units to three deaths per 1000 deliveries at 40 weeks' gestation approximately doubles on 42 weeks and is four to six times greater at 44 weeks. (45)

Risks of postponeed Gestation

Post-term pregnancies are associated with numerous adverse consequences (Table 1). (1) In a fresh Danish birth-registry study, (1) increased rates of multiple maternal and perinatal complications were base in singleton pregnancies of at least 42 weeks' gestation. The risks were not limited to deliveries of large infants; the underlying causes of the continue lengthen in timeed pregnancies also may have been responsible. The incident of complications was particularly high in low-birth-weight infants and likely ensueed from the cause of fetal vegetation restriction. A Norwegian birth cohort thought (3) found that maternal complications usually are associated with larger fetal size, and fetal complications are associated with smaller size. When these factors are considered, the impact of post-term pregnancies is minor by means of comparison.

Review of the Evidence

The management of pregnancy beyond 40 weeks' gestation relies forward an accurate assessment of the gestational age. A Cochrane review (6) establish that, compared with selective ultrasonography, routine prenatal ultrasonography before 24 weeks' gestation provides better gestational age assessment and earlier detection of multiple pregnancies and fetal malformations. In a retrospective consideration (7) of more than 34000 pregnant women with "certain" menstrual dates (i.e., patient stated that she was assured of her dates, that she had regular menstrual round of yearss and that she had not taken oral contraceptive pills in the preceding three months) ultrasound dating during the estimated gestational age range of 13 to 24 weeks gave a more accurate prediction of the delivery date than estimates based onward the last menstrual period alone or in combination with ultrasonography. Early ultrasound dating also comeed in a 70 per-cent reduction in the number of pregnancies that were considered post-term

Elective labor induction before 42 weeks' gestation has been propos to abridge rates of adverse fetal and maternal complications. The Canadian Multicenter Post-term Pregnancy Trial (CMPPT) (8) is the largest individual randomized controll trial (RCT) to date comparing labor induction at 41 weeks with expectant management. In this thought 3,407 women with pregnancies of at least 41 weeks' gestation were randomized to immediate induction or expectant management with fetal monitoring. Monitoring consisted of daily kick judges nonstress tests (NSTs) three times through week (Table 2), (9) and ultrasound amniotic-fluid-volume assessments couple or three times per week (Table 3) (10-12) Expectant management continued until 44 weeks' gestation or until there was an obstetric indication for labor induction. The expectant management assemblage had a significantly higher rate of cesarean deliveries than the induction arrange (odds ratio [OR], 1.22; 95 percent confidence interval [CI], 102 to 145; number distressed to induce to prevent individual excess cesarean delivery, 30). The expectant management assign places to had a significantly higher rate of cesarean deliveries resulting from fetal distress, yet there was no difference between assign places tos in the rate of cesarean deliveries resulting from dystocia. No difference was institute in perinatal mortality rates, although the contemplation was too under-powered to find this outcome. No differences were ground in neonatal morbidity outcomes.

A Cochrane review (13) of 19 RCT ground that routine labor induction at 41 weeks' gestation originateed in lower perinatal mortality rates further similar cesarean delivery rates. Approximately 500 women exigencyed to be induced to obstruct one perinatal death, and the number may be higher in current-day practice. Meconium-stained amniotic fluid was more public in the expectant management dispose but rates of meconium aspiration syndrome and other neonatal morbidities were not significantly different between collections This review also found that routine ultrasonography in early pregnancy-- flat in low-risk women--reduced the number of patients who required labor induction for apparent post-term pregnancies.