The clinical practice pattern of postterm pregnancy in Korea / 대한산부인과학회지

OBJECTIVE: The purpose of this study is to survey the clinical practice pattern of postterm pregnancy in Korea. METHODS: A questionnaire was mailed to 1114 physicians who are registered in Korean Society of Obstetrics and Gynecology (KSOG) and work in primary and secondary hospital as well as tertiary care center. The questions included information about the practice pattern implicating definition of postterm pregnancy, the time and the method of routine fetal surveillance and induction of labor as well as demographic information such as age, sex, location, professional part and the number of delivery. We got 23.2% (258/1114) of surveys returned and analyzed the data. RESULTS: Seventy-four percent (73.6%) of the respondents define 42 weeks gestation or greater to be postterm. However, 84.5% consider induction of labor at 41 weeks of gestation. Sixty-eight percent (68.3%) of the respondents start postterm pregnancy fetal testing at 40 weeks and 59.3% of them perform testing every week. For fetal surveillance testing, 85.7% of the respondents use NST and 39.5% of them use modified BPP. As for induction of labor, 65% of practitioners use oxytocin and 45% of them use prostaglandins (misoprostol and dinoprostone) when inducing both nulliparous and multiparous women with unfavorable cervix. CONCLUSION: Most of the respondents (84.5%) routinely induce low-risk singleton pregnancy at 41 weeks gestation, whereas the majority of them (73.6%) define postterm pregnancy beyond 42 weeks gestation.

The Course of Delivery and Perinatal Outcomes for Postterm Pregnancy / 대한산부인과학회잡지

OBJECTIVE: The purpose of this study was to evaluate of course of delivery & perinatal outcomes for postterm pregnancy compared with fullterm pregnancy. METHODS: This study included 360 cases of postterm pregnancy out of 16,992 cases delivered at Department of Obstetrics and Gynecology from January 1, 1993 to December 31, 1997. 16,143 cases of full term deliveries of 38 to 42 gestational weeks conducted in same period were used as the control group. Postterm pregnancy was defined as a pregnancy that it exceeds 295 days calculated from first day of the last menstrual period. RESULTS: The incidence of postterm pregnancy was 2.13% with the highest incidence occurring in the 26 ~30 years age group. This study group was significantly different from the control group in the incidence of fetal distress (10.28% vs. 2.20%), large fetus (10.83% vs. 6.95%), perinatal death (1.67% vs. 0.27%). CONCLUSIONS: Adverse perinatal outcomes were increased markedly as the gestational weeks to be prolonged. Therefore, careful prenatal care, accurate determination of delivery date is very important.

Amniotic Fluid Index and Preinatal Outcome in Postterm Pregnancy / 대한주산의학회잡지

A pregnancy is considered postterm if it is beyond 294 days (42 complete weeks). Several investigators have demonstrated that postterm pregnancy may be accompanied by a rise in perinatal morbidity and/or mortality. Abnormalities such as meconium staining, cringenital anomalies, intrauterine growth retardation, postmaturity syndrome, fetal asphyxia have been reported in some cases of reduced amniotic fluid volume (oligohyramnios) which is commonly observed in postterm pregnancies. Amniotic fluid volume has been shown to decrease significantly as gestational age advances beyond term. Oligohydramnios has particular relevance to postterm pregnancies. Poor perinatal outcomes of oligohydramnios on postterm pregnancy have been reported by several authors. To date, however, the relationship between oligohydramnios in pastterm pregnancy and fetal outcome is debatable. The purpose of this clinical study was to evaluate the relationship between oligohydr- amnios and perinatal outcome in 64 cases of postterm pregnancies. Amniotic fluid index(AFI) values were measured semiweekly in 64 good dated, uncomplicated singleton pregnancies. AFI values were categorized into 2 groups. The group 1; patients whose final AFI value was above 5.0 cm; Group 2, patients whose AFI value fell below 5.0 cm. Adverse fetal outcome was defined by the presence of meconium staining, fetal heart rate decelerations, cesarean delivery for fetal distress, low Apgar score at 1 and 5 minutes, neonatal intensive care unit admission, and perinatal mortality. The fetal outcome was compared group 1 with group 2 and results obtained were as follows: 1. The incidence of oligohydramnios in postterm pregnancy was 54.7 %. The average diminution of amniotic fluid index was from 8.2 1.8 cm to 5.6+2.2 cm/week. 2. The incidence of meconium-staining in amniotic fluid was 40.6 % (Group 1: 20.7 %, Group 2: 57.1 %) and showed statistically significant difference between the two groups(p= 0.003). 3. The incidence of Apgar score less than 7 was 23.4% in 1 minute (Group 1: 13.8 %, Group 2: 31.4 %) and 4.7 % in 5 minutes(Group 1: 3.4%, Group 2: 5.7 %), respectively and showed no statistically significant difference between the two groups (p=0.140, p=1.000). 4. I'he incidence of cesarean delivery due to fetal distress was 12.5 % (Group 1: 6.9%, Group 2: 17.1 %) and showed no statistically significant difference between the two groups (p=0.275). 5. The incidence of admission to NICU was 12.5 % (Group 1: 6.9%, Group 2: 17.1 %) and showed no statistically significant difference between the two groups (p=0.275). Adverse fetal outcome was not uniformly observed in postterm pregnancies with oligohydramnios. Amniotic fluid index in oligohydramnios group as a single independent guide was not enough to predict fetal outcomes in postterm pregnancy without specific pathologic condition of fetus.