The effect of placenta previa on neonatal mortality: a population-based study in the United States, 1989 through 1997

OBJECTIVE: The purpose of the study was to explore the associations of placenta previa with preterm delivery, growth restriction, and neonatal survival. STUDY DESIGN: A retrospective cohort study was performed of live births in the United States (1989-1991 and 1995-1997) that used the national linked birth/infant death records from 22,368,235 singleton pregnancies. The diagnosis of previa was restricted to those live births that were delivered (> or =24 weeks) by cesarean delivery. We evaluated gestational age and birth weight-specific risk of neonatal deaths (within the first 28 days) in relation to placenta previa. Fetal growth was assessed in centiles of birth weight (<3rd, 3rd-4th, 5th-9th, 10th-90th, and >90th centile), adjusted for gestational age. All analyses were adjusted for the confounding effects of the year of delivery, maternal age, gravidity, education, prenatal care, marital status, and race/ethnicity. RESULTS: Placenta previa was recorded in 2.8 per 1000 live births (n = 61,711). Neonatal mortality rate was 10.7 with previa, compared with 2.5 per 1,000 among other pregnancies (relative risk, 4.3; 95% confidence interval, 4.0,4.8). At 28 to 36 weeks, babies born to women with placenta previa weighed, on average, 210 g lower than babies born to women without placenta previa (P <.001). Compared with babies born to women without previa, the risk of death from placenta previa was lower among preterm babies (<37 weeks of gestation), with a crossover at 37 weeks where the mortality rate was higher for babies born to women with placenta previa than for babies born to women without placenta previa. This crossover also persisted in an analysis by birth weight and term births (delivered at > or =37 weeks of gestation). Mortality rates for term births were higher among babies born to women with placenta previa than among babies born women without placenta previa who were at the 10th to 90th centile (relative risk, 1.9; 95% confidence interval, 1.3, 2.8), and those at >90th centile (relative risk, 3.6; 95% confidence interval, 1.3, 9.6). Among preterm births, however, placenta previa was not associated with increased neonatal mortality by fetal growth centiles. CONCLUSION: The risk of neonatal mortality was higher for babies born to women with placenta previa than for babies born to women without placenta previa who were delivered at > or =37 weeks of gestation. Pregnancies that are diagnosed with placenta previa must be monitored carefully, especially as they approach term.     

Placenta previa: neonatal death after live births in the United States

OBJECTIVE: The purpose of this study was to describe neonatal mortality rates among live births that were complicated by placenta previa in the United States. STUDY DESIGN: This was a population-based retrospective cohort study of 1997 United States singleton live births. Neonatal deaths among pregnancies that were complicated by placenta previa were compared with deaths among pregnancies with no placenta previa. Adjusted and unadjusted hazard ratios were generated from a proportional hazards regression model. RESULTS: Of 3,773,369 live births, 9656 were complicated by placenta previa (2.6 cases per 1000). Among cases of placenta previa, 114 neonatal deaths occurred (11.8 per 1000) versus 14951 (4 per 1000) among non-placenta previa neonates (P <.0001). The adjusted relative risk of death was three times higher among placenta previa neonates (hazard ratio, 3.06; 95% CI, 2.40-3.94). Placenta previa-related death was mediated through preterm delivery rather than small for gestational age. CONCLUSION: Placenta previa triples the rate of neonatal mortality, which is mediated mainly through preterm birth.     

Placenta previa in twin gestations

The incidence of placenta previa in twin gestations was compared to that found in singleton pregnancies over a ten-year period. During this period, eight placenta previas occurred in 1,464 twin pregnancies, for an incidence of 0.55%, which was significantly higher (P less than .05) than the incidence of 0.31% in singleton pregnancies (458 placenta previas in 148,197 singleton pregnancies). We conclude that a twin gestation confers an added risk of placenta previa.     

Induced abortion and placenta complications in the subsequent pregnancy

BACKGROUND: To study the risk of placenta complications following an induced abortion as a function of the interpregnancy interval. METHODS: This study is based on three Danish national registries; the Medical Birth Registry, the Hospital Discharge Registry, and the Induced Abortion Registry. All primigravida women from 1980 to 1982 were identified in these three registries. A total of 15,727 women who terminated the pregnancy with a first trimester induced abortion were selected to the abortion cohort, and 46,026 women who did not terminate the pregnancy with an induced abortion constituted the control cohort. By register linkage all subsequent pregnancies were identified from 1980 to 1994. Only women who had a non-terminated pregnancy following the index pregnancy were selected to the study. Placenta complications were identified using either the Hospital Discharge Registry ICD-8 codes or the Medical Birth Registry records. RESULTS: A slightly higher risk of placenta complications following an abortion was found. Retained placenta occurred more frequently in women with one, two or more previous abortions, compared with women without any previous abortion of similar gravidity. Adjusting for maternal age and residence at time of pregnancy, the interpregnancy interval, and the number of previous miscarriages (control cohort only), the odds ratios of retained placenta in deliveries of singleton live births in women with one previous abortion was 1.17 (95%CI=1.02-1.35), and for women with two or more previous abortions it was 1.68 (95%CI=1.23-2.30), respectively, compared with the control cohort of similar gravidity. Only for women who had one abortion did the results follow the predicted pattern of a higher risk of retained placenta after a short pregnancy interval. No association with placenta previa was seen. CONCLUSIONS: The findings suggest a positive association between abortions and retained placenta in subsequent singleton live births, but the association was weak and confounding cannot be ruled out.     

Previous cesarean delivery and risks of placenta previa and placental abruption

OBJECTIVE: To examine the association between cesarean delivery and previa and abruption in subsequent pregnancies. METHODS: A retrospective cohort study of first 2 (n = 156,475) and first 3 (n = 31,102) consecutive singleton pregnancies using the 1989-1997 Missouri longitudinally linked data were performed. Relative risk (RR) was used to quantify the associations between cesarean delivery and risks of previa and abruption in subsequent pregnancies, after adjusting for several confounders. RESULTS: Rates of previa and abruption were 4.4 (n = 694) and 7.9 (n = 1,243) per 1,000 births, respectively. The pregnancy after a cesarean delivery was associated with increased risk of previa (0.63%) compared with a vaginal delivery (0.38%, RR 1.5, 95% confidence interval [CI] 1.3-1.8). Cesarean delivery in the first and second births conferred a two-fold increased risk of previa in the third pregnancy (RR 2.0, 95% CI 1.3-3.0) compared with first two vaginal deliveries. Women with a cesarean first birth were more likely to have an abruption in the second pregnancy (0.95%) compared with women who had a vaginal first birth (0.74%, RR 1.3, 95% CI 1.2-1.5). Two consecutive cesarean deliveries were associated with a 30% increased risk of abruption in the third pregnancy (RR 1.3, 95% CI 1.0-1.8). A second pregnancy within a year after a cesarean delivery was associated with increased risks of previa (RR 1.7, 95% CI 0.9-3.1) and abruption (RR 1.5, 95% CI 1.1-2.3). CONCLUSION: A cesarean first birth is associated with increased risks of previa and abruption in the second pregnancy. There is a dose-response pattern in the risk of previa, with increasing number of prior cesarean deliveries. A short interpregnancy interval is associated with increased risks of previa and abruption. LEVEL OF EVIDENCE: II-2.     

Obstetric and neonatal risk of pregnancies after assisted reproductive technology: a matched control study

BACKGROUND: The aim of the study was to evaluate the obstetric and neonatal outcome of pregnancies after assisted reproduction technology (ART) in comparison with matched controls from spontaneous pregnancies. METHODS: A total of 12 920 deliveries at the Department of Obstetrics and Gynecology, University of Szeged, from 1 January 1995 to 31 December 2001 were subjected to retrospective analysis. Two hundred and eighty-four singleton, 75 twin and 17 triplet pregnancies after ovulation induction (n = 114; 30.3%), intrauterine insemination (n = 33; 8.8%) and in vitro fertilization (n = 229; 60.9%) were evaluated. The pregnancy outcome of the singleton and twin pregnancies was compared with that for controls matched with regard to age, gravidity and parity and previous obstetric outcome after spontaneous pregnancies. RESULTS: Twenty-four percent of the assisted reproductive pregnancies were multiple pregnancies. The incidences of singleton intrauterine growth retardation (IUGR) and preterm birth were reasonably similar to those among the controls (IUGR: 6.3% vs. 4.2%; preterm births: 13.0% vs. 9.9%, for the cases and the controls, respectively). As compared with the controls, there was an increased incidence of cesarean section among the singleton (41.2% vs. 34.5%, p = 0.12; OR 1.33; 95% CI 0.95-1.87) and twin assisted reproduction pregnancies (66.7% vs. 60.0%), but without significant differences. CONCLUSIONS: Increased obstetric risk could be observed concerning threatened preterm delivery and cesarean section rate in the study group. The perinatal outcome of singleton and twin pregnancies following assisted reproductive techniques is comparable with that of spontaneously conceived, matched pregnancies.     

Pregnancy-related mortality among women with multifetal pregnancies

OBJECTIVE: To examine the relative risk of pregnancy-related mortality between multifetal pregnancies and singleton pregnancies. METHODS: We used data from the Centers for Disease Control and Prevention's Pregnancy Mortality Surveillance System to examine singleton and multifetal pregnancy-related deaths among women with a live birth or fetal death from 1979-2000. The plurality-specific (singleton or multifetal) pregnancy-based mortality ratio was defined as the number of pregnancy-related deaths per 100,000 pregnancies with a live birth. We analyzed the risk of death due to pregnancy for singleton and multifetal pregnancies by age, race, education, marital status, and cause of death. RESULTS: Of 4,992 pregnancy-related deaths in 1979-2000, 4.2% (209 deaths) were among women with multifetal pregnancies. The risk of pregnancy death among women with twin and higher-order pregnancies was 3.6 times that of women with singleton pregnancies (20.8 compared with 5.8). The leading causes of death were similar for women with singleton pregnancies and women with multifetal pregnancies: embolism, hypertensive complications of pregnancy, hemorrhage, and infection. CONCLUSION: Women with multifetal pregnancies have a significantly higher risk of pregnancy-related death than their counterparts with singleton pregnancies; this holds true for all women regardless of age, race, marital status, and level of education. LEVEL OF EVIDENCE: II-2.     

Effect on neonatal outcomes in gestational hypertension in twin compared with singleton pregnancies

OBJECTIVE: We tested the hypothesis that gestational hypertension may have a more benign effect on neonatal outcomes in twin compared with singleton pregnancies, because the elevated blood pressure in twin pregnancies may partly or merely reflect the extra demand for blood supply. METHODS: A retrospective cohort study of 102,988 twin and 5,523,797 singleton live births using the U.S. birth cohort linked birth and infant death data sets, 1998-2000. Main outcomes are relative risks (RRs) of adverse neonatal outcomes: preterm birth, intrauterine growth restriction (less than the third percentile), low 5-minute Apgar score (less than 4), and neonatal death comparing gestational hypertensive with no-event healthy pregnancies for twins and singletons. RESULTS: For singletons, crude RRs (95% confidence intervals) comparing gestational hypertensive with healthy pregnancies were 2.23 (2.20-2.25) for preterm birth (17.4 compared with 7.8%), 2.49 (2.45-2.53) for intrauterine growth restriction (7.4 compared with 3.0%), 1.33 (1.21-1.45) for low 5-minute Apgar score (2.6 compared with 2.0 per 1,000), and 1.07 (0.96-1.19) for neonatal death (1.9 compared with 1.8 per 1,000), respectively. For twins, the corresponding RRs were much lower or showed reversed associations: 1.21 (1.19-1.24) (63.6 compared with 52.4%), 1.04 (0.98-1.11) (16.4 compared with 16.4%), 0.32 (0.23-0.46) (4.1 compared with 12.7 per 1,000), and 0.21 (0.14-0.30) (3.6 compared with 17.2 per 1,000), respectively. The adjusted odds ratios showed a similar risk pattern in twin compared with singleton pregnancies after controlling for maternal race, age, education, marital status, parity, smoking, alcohol use, perinatal care use, and mode of delivery. CONCLUSION: Gestational hypertension has a much more benign effect on neonatal outcomes in twin compared with singleton pregnancies. There might be a need for twin- or multiple fetus-specific recommendations for hypertension management in pregnancy, but further interventional studies are needed to test the hypothesis. LEVEL OF EVIDENCE: II-2.     

Maternal and obstetric risk factors for sudden infant death syndrome in the United States

OBJECTIVE: The objectives of this study were to 1). study the incidence of sudden infant death syndrome (SIDS) among singleton births in the United States and 2). identify maternal and obstetric risk factors for SIDS. METHODS: A cohort of all live births in the United States from 1995 to 1998, formed the source population (n = 15627404). The data were obtained from the National Centers for Health Statistics Linked Births and Infant Deaths File. A nested case-control study was used to examine risk factors for SIDS. From this birth cohort, all SIDS deaths (n = 12404) were first identified (case group). From the remaining non-SIDS births, a 4-fold larger sample (n = 49616) was randomly selected as a control group. RESULTS: The overall incidence of SIDS was 81.7 per 100000 live births. More mothers in the case group than in the control group were reported to have placenta previa (odds ratio [OR]: 1.70; 95% confidence interval [CI] 1.24, 2.33), abruptio placentae (OR 1.57; 95% CI 1.24, 1.98), premature rupture of membranes (OR 1.48; 95% CI 1.33, 1.66), or small for gestational age (OR 1.40; 95% CI 1.30, 1.50 for the 10th percentile). SIDS cases were also more likely to be male. Mothers of cases were more likely to be younger, less educated, and nonwhite, and more of them smoked during pregnancy and did not attend prenatal care. CONCLUSION: This analysis confirms the importance of several well known demographic and lifestyle risk factors for SIDS. In addition, placental abnormalities were risk factors for SIDS. LEVEL OF EVIDENCE: II-2     

Neonatal outcomes with placenta previa

OBJECTIVE: To identify neonatal complications associated with placenta previa. METHODS: This was a population-based, retrospective cohort study involving all singleton deliveries in Nova Scotia from 1988 to 1995. The study group consisted of all completed singleton pregnancies complicated by placenta previa; all other singleton pregnancies were considered controls. Patient information was collected from the Nova Scotia Atlee perinatal database. Neonatal complications were evaluated while controlling for potential confounders. The data were analyzed using chi2, Fisher exact test, and multiple logistic regression. RESULTS: Among 92,983 pregnancies delivered during the study period, 305 cases of placenta previa were identified (0.33%). After controlling for potential confounders, neonatal complications significantly associated with placenta previa included major congenital anomalies (odds ratio [OR] 2.48), respiratory distress syndrome (OR 4.94), and anemia (OR 2.65). The perinatal mortality rate associated with placenta previa was 2.30% (compared with 0.78% in controls) and was explained by gestational age at delivery, occurrence of congenital anomalies, and maternal age. Although there was a higher rate of preterm births in the placenta previa group (46.56% versus 7.27%), there was no difference in birth weights between groups after controlling for gestational age at delivery. CONCLUSION: Neonatal complications of placenta previa included preterm birth, congenital anomalies, respiratory distress syndrome, and anemia. There was no increased occurrence of fetal growth restriction.     

Obstetric history and the risk of placenta previa

OBJECTIVE: To evaluate secular trends in the occurrence of placenta previa and whether placenta previa is associated with the outcome of previous pregnancies, cesarean section, and sociodemographic factors. DESIGN: A cohort study based on the Medical Birth Registry of Norway. Placenta previa in the second pregnancy was investigated for associations with outcomes in the first pregnancy and sociodemographic factors. RESULTS: In birth orders 1 and 2 the occurrence of placenta previa was 1.2 and 2.2 per 1,000, respectively, with no secular trend. The occurrence increased with maternal age and was lowest in women aged 20-29 years. The recurrence rate was 23 per 1,000 (adjusted odds ratio (OR) of recurrence=9.7). In women with prior delivery at < or =25 gestational weeks the risk of placenta previa was 6.7 per 1,000 (adjusted OR=3.0). In women with prior placental abruption the risk was 5.8 per 1,000 (OR=2.6). In women with prior perinatal death the risk was 4.4 per 1,000 (adjusted OR= 1.8). No independent relationship emerged with socio-economic factors, previous birthweight, and a history of pregnancy induced hypertension. Cesarean section was associated with subsequent development of placenta previa (adjusted OR= 1.3). CONCLUSIONS: We found no secular trends in the occurrence of placenta previa. Placenta previa is associated with previously described risk factors for placental abruption. The increased risk of placenta previa subsequent to placental abruption supports the theory of a shared etiologic factor. However, placenta previa and placental abruption do not share a common etiology in relation to a history of pregnancy induced hypertension, fetal growth retardation, and socio-economic factors.     

Relationship among placenta previa, fetal growth restriction, and preterm delivery: a population-based study

OBJECTIVE: To examine the independent contributions of prematurity and fetal growth restriction to low birth weight among women with placenta previa. METHODS: A population-based, retrospective cohort study of singleton live births in New Jersey (1989-93) was performed. Mother-infant pairs (n = 544,734) were identified from linked birth certificate and maternal and infant hospital discharge summary data. Women diagnosed with previa were included only if they were delivered by cesarean. Fetal growth, defined as gestational age-specific observed-to-expected mean birth weight, and preterm delivery (before 37 completed weeks) were examined in relation to previa. Severe and moderate categories of fetal smallness and large for gestational age were defined as observed-to-expected birth weight ratios below 0.75, 0.75-0.85, and over 1.15, respectively, all of which were compared with appropriately grown infants (observed-to-expected birth weight ratio 0.86-1.15). RESULTS: Placenta previa was recorded in 5.0 per 1000 pregnancies (n = 2744). After controlling for maternal age, education, parity, smoking, alcohol and illicit drug use, adequacy of prenatal care, maternal race, as well as obstetric complications, previa was associated with severe (odds ratio [OR] 1.37, 95% confidence interval [CI] 1.25, 1.50) and moderate fetal smallness (OR 1.24, 95% CI 1.17, 1.32) births. Preterm delivery was also more common among women with previa. Adjusted OR of delivery between 20-23 weeks was 1.81 (95% CI 1.24, 2.63), and 2.90 (95% CI 2.46, 3.42) for delivery between 24-27 weeks. OR for delivery by each week between 28 and 36 weeks ranged between 2.7 and 4.0. Approximately 12% of preterm delivery and 3.7% of growth restriction were attributable to placenta previa. CONCLUSION: The association between low birth weight and placenta previa is chiefly due to preterm delivery and to a lesser extent with fetal growth restriction. The risk of fetal smallness is increased slightly among women with previa, but this association may be of little clinical significance.     

Risk of preterm delivery in singletons conceived by in vitro fertilization

To evaluate the preterm delivery and other obstetrics complications similar in singleton pregnancies achieved through IVF compared to spontaneous pregnancies. Retrospective case-control study included 1663 women with singleton pregnancies following IVF-ICSI (study group) and 3326 women with singleton spontaneous pregnancies (control group) who delivered between January 2015 and January 2018 at the Peking University Third Hospital. The control group matched 1:2 by age, BMI, parity, and gravidity. Maternal outcomes included preterm delivery and complications. There was significantly higher incidence of gestational diabetes, hypertensive disorders, and placenta previa in IVF-ICSI pregnancies versus controls (p?<?.05). IVF-ICSI resulted in significantly higher rate of preterm birth than in spontaneous pregnancies (p?<?.05) and the difference remained significant for deliveries that occurred before 28, 32, and 34?weeks gestation (p?<?.05). Multivariate logistic regression analysis revealed that female-factor infertility, hypertensive disorder, placenta previa, and PROM were significant prognostic factors associated with increased risk of prematurity. IVF-ICSI is associated with increased risk of obstetric complications including preterm delivery in singleton pregnancies. Female-factor infertility is an independent prognostic factor for preterm birth. This information is important for patient counseling and helps to refine the recommendation to optimize maternal health before embarking on fertility treatments.     

The impact of prenatal care on neonatal deaths in the presence and absence of antenatal high-risk conditions

OBJECTIVE: The purpose of this study was to determine the association between prenatal care in the United States and the neonatal death rate in the presence and absence of antenatal high-risk conditions. STUDY DESIGN: Data were derived from the national perinatal mortality data sets for the years 1995 through 1997, which were provided by the National Center for Health Statistics. Analyses were restricted to singleton live births that occurred after 23 completed weeks of gestation. Multivariable logistic regression analyses were used to adjust for the presence or absence of various antenatal high-risk conditions, maternal age, gestational age at delivery, and birth weight. RESULTS: Of 10,530,608 singleton live births, 18,339 (1.7/1000 births) resulted in neonatal death. Neonatal death rates (per 1000 live births) were higher for African American infants compared with white infants in the presence (2.7 vs 1.5, respectively) and absence (10.7 vs 7.9, respectively) of prenatal care. Lack of prenatal care was associated with an increase in neonatal deaths, which was greater for infants born at > or =36 weeks of gestation (relative risk, 2.1; 95% CI, 1.8, 2.4). Lack of prenatal care was also associated with increased neonatal death rates in the presence of preterm premature rupture of the membranes (relative risk, 1.3; 95% CI, 1.1, 1.5), placenta previa (relative risk, 1.9; 95% CI, 1.2, 2.9), fetal growth restriction (relative risk, 1.7; 95% CI, 1.2, 1.6), and postterm pregnancy (relative risk, 1.4; 95% CI, 1.0, 2.9). CONCLUSION: In the United States, prenatal care is associated with fewer neonatal deaths in black and white infants. This beneficial effect was more pronounced for births that occurred at > or =36 weeks of gestation and in the presence of preterm premature rupture of the membranes, placenta previa, fetal growth restriction, and postterm pregnancy.     

Association of caesarean delivery for first birth with placenta praevia and placental abruption in second pregnancy

Objective  To quantify the risk of placenta praevia and placental abruption in singleton, second pregnancies after a caesarean delivery of the first pregnancy.
Design  Retrospective cohort study.
Setting  Linked birth and infant mortality database of the USA between 1995 and 2000.
Population  A total of 5 146 742 singleton second pregnancies were available for the final analysis after excluding missing information.
Methods  Multiple logistic regressions were used to describe the relationship between caesarean section at first birth and placenta praevia and placental abruption in second-birth singletons.
Main outcome measures  Placenta praevia and placental abruption.
Results  Placenta praevia was recorded in 4.4 per 1000 second-birth singletons whose first births delivered by caesarean section and 2.7 per 1000 second-birth singletons whose first births delivered vaginally. About 6.8 per 1000 births were complicated with placental abruption in second-birth singletons whose first births delivered by caesarean section and 4.8 per 1000 birth in second-birth singletons whose first births delivered vaginally. The adjusted odds ratio (95% CIs) of previous caesarean section for placenta praevia in following second pregnancies was 1.47 (1.41, 1.52) after controlling for maternal age, race, education, marital status, maternal drinking and smoking during pregnancy, adequacy of prenatal care, and fetal gender. The corresponding figure for placental abruption was 1.40 (1.36, 1.45).
Conclusion  Caesarean section for first live birth is associated with a 47% increased risk of placenta praevia and 40% increased risk of placental abruption in second pregnancy with a singleton.     

A parsimonious explanation for intersecting perinatal mortality curves: understanding the effect of plurality and of parity

BACKGROUND: Birth weight- and gestational age-specific perinatal mortality curves intersect when compared across categories of maternal smoking, plurality, race and other factors. No simple explanation exists for this paradoxical observation. METHODS: We used data on all live births, stillbirths and infant deaths in Canada (1991-1997) to compare perinatal mortality rates among singleton and twin births, and among singleton births to nulliparous and parous women. Birth weight- and gestational age-specific perinatal mortality rates were first calculated by dividing the number of perinatal deaths at any given birth weight or gestational age by the number of total births at that birth weight or gestational age (conventional calculation). Gestational age-specific perinatal mortality rates were also calculated using the number of fetuses at risk of perinatal death at any given gestational age. RESULTS: Conventional perinatal mortality rates among twin births were lower than those among singletons at lower birth weights and earlier gestation ages, while the reverse was true at higher birth weights and later gestational ages. When perinatal mortality rates were based on fetuses at risk, however, twin births had consistently higher mortality rates than singletons at all gestational ages. A similar pattern emerged in contrasts of gestational age-specific perinatal mortality among singleton births to nulliparous and parous women. Increases in gestational age-specific rates of growth-restriction with advancing gestational age presaged rising rates of gestational age-specific perinatal mortality in both contrasts. CONCLUSIONS: The proper conceptualization of perinatal risk eliminates the mortality crossover paradox and provides new insights into perinatal health issues.     

Obstetric outcomes in 102 pregnancies after preimplantation genetic diagnosis

OBJECTIVE: We sought to determine whether preimplantation genetic diagnosis is associated with particular pregnancy or delivery complications. STUDY DESIGN: A total of 102 consecutive pregnancies after preimplantation genetic diagnosis by polar body removal performed at Illinois Masonic Medical Center resulting in 114 live births were analyzed. All patients were given a delivery and newborn questionnaire, and attempts were made to contact and question them regarding any pregnancy complications and type of delivery. Permission was obtained to examine medical records and discuss the patient's pregnancy with her obstetrician when questions existed with respect to complications or indication for cesarean delivery. RESULTS: Delivery and newborn questionnaires were completed or telephone contact was achieved for 100 of the 102 pregnancies. There were 85 singleton, 9 twin, and 7 triplet pregnancies. Of the 7 triplet gestations, 3 couples elected multifetal pregnancy reduction to twins and healthy triplets were born to 4 couples between 32 and 36 weeks by cesarean delivery. Of the 80 singleton deliveries, 60 (75%) progressed to term. Of these 60 term singleton deliveries, 34 were vaginal, 23 were cesarean (40%), and 3 delivery types were unknown. The incidence of small-for-gestational-age infants was 3% for neonates in the 60 term singleton deliveries and 7% in the entire cohort of 80 singleton deliveries. Only 3 pregnancy complications (other than premature delivery) were reported more than once. There were 3 instances each of gestational diabetes, intrauterine growth restriction, and pregnancy-induced hypertension. There was 1 case each of HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome, congestive heart failure, mild oligohydramnios, and abruptio placentae. The indications for cesarean delivery were (in descending order) failure of labor to progress (n = 7), fetal distress (n = 4), placenta previa (n = 4), elective repeat cesarean delivery (n = 4), triplets (n = 3), uterine scarring (n = 3), 1 twin in the breech position (n = 3), failed forceps delivery (n = 2), and a variety of other indications that occurred in only 1 patient each. All preimplantation genetic diagnoses were confirmed by prenatal or postnatal testing. No diagnostic errors were made in this cohort of patients or in any patients undergoing preimplantation genetic diagnosis having polar body removal in our center. CONCLUSIONS: Preimplantation genetic diagnosis is associated with a risk of multiple gestations, cesarean delivery, and placenta previa. Cesarean delivery rates and multiple gestation rates are comparable to those of patients undergoing in vitro fertilization in general. The preimplantation genetic diagnosis itself does not seem to cause an increased risk for any particular pregnancy complication, with the possible exception of placenta previa, which was seen in 4% of patients.     

Risk factors for postpartum hemorrhage requiring transfusion in cesarean deliveries for Japanese twins: comparison with those for singletons

Objective

The aim of this study was to identify the factors associated with the increased risk of postpartum hemorrhage requiring transfusion in Japanese twin pregnancies in comparison with those in Japanese singleton pregnancies.

Methods

We reviewed the obstetric records of all singleton and twin deliveries after 22?weeks’ gestation at the Japanese Red Cross Katsushika Maternity Hospital from 2003 through 2011. Potential risk factors for transfusion due to hemorrhage after cesarean delivery were selected according to previous studies of postpartum hemorrhage or transfusion or both after delivery: maternal age, parity, previous cesarean deliveries, history of infertility therapies such as in vitro fertilization, gestational age at delivery, neonatal birth weight, placenta previa, uterine myoma ≥6?cm, hypertensive disorders, placental abruption, emergency cesarean deliveries and general anesthesia.

Results

Using multiple logistic regression, the independent risk factors for postpartum hemorrhage requiring transfusion in singleton pregnancies were preterm delivery [odds ratio (OR) 2.40, 95?% confidence interval (CI) 1.2–4.6, p?<?0.01], placenta previa (OR 8.08, 95?% CI 3.9–16, p?<?0.01) and placental abruption (OR 12.8, 95?% CI 2.3–76, p?<?0.01). In twin pregnancies, however, the independent risk factors for postpartum hemorrhage requiring transfusion were gestational age at ≥41?weeks (OR 8.20, 95?% CI 1.3–40, p?<?0.01) and hypertensive disorders (OR 5.45, 95?% CI 2.2–14, p?<?0.01).

Conclusions

The factors associated with postpartum hemorrhage requiring transfusion in cesarean deliveries of twins seemed to be different from those in singleton cesarean deliveries.     

Placenta previa: obstetric risk factors and pregnancy outcome

Objective: To determine the incidence, obstetric risk factors and perinatal outcome of placenta previa. Study design: All singleton deliveries at our institution between 1990 and 1998 complicated with placenta previa were compared with those without placenta previa. Results: Placenta previa complicated 0.38% ( n = 298) of all singleton deliveries ( n = 78 524). A back-step multiple logistic regression model found the following factors to be independently correlated with the occurrence of placenta previa: maternal age above 40 years (OR 3.1, 95% CI 2.0-4.9), infertility treatments (OR 3.1, 95% CI 1.8-5.6), a previous Cesarean section (OR 1.8, 95% CI 1.4-2.4), a history of habitual abortions (OR 1.3, 95% CI 1.3-2.7) and Jewish ethnicity (OR 1.3, 95% CI 1.1-1.8). Pregnancies complicated with placenta previa had significantly higher rates of second-trimester bleeding (OR 156.0, 95% CI 87.2-277.5), pathological presentations (OR 7.6, 95% CI 5.7-10.1), abruptio placentae (OR 13.1, 95% CI 8.2-20.7), congenital malformations (OR 2.6, 95% CI 1.5-4.2), perinatal mortality (OR 2.6, 95% CI 1.1-5.6), Cesarean delivery (OR 57.4, 95% CI 40.7-81.4), Apgar scores at 5 min lower than 7 (OR 4.4, 95% CI 2.3-8.3), placenta accreta (OR 3.6, 95% CI 1.1-9.9) postpartum hemorrhage (OR 3.8, 95% CI 1.2-10.5), postpartum anemia (OR 5.5, 95% CI 4.4-6.9) and delayed maternal and infant discharge from the hospital (OR 10.9, 95% CI 7.3-16.1) as compared to pregnancies without placenta previa. In a multivariable analysis investigating risk factors for perinatal mortality, the following were found to be independent significant factors: congenital malformations, placental abruption, pathological presentations and preterm delivery. In contrast, placenta previa and Cesarean section were found to be protective factors against the occurrence of perinatal mortality while controlling for confounders. Conclusion: Although an abnormal implantation per se was not an independent risk factor for perinatal mortality, placenta previa should be considered as a marker for possible obstetric complications. Hence, the detection of placenta previa should encourage a careful evaluation with timely delivery in order to reduce the associated maternal and perinatal complications.     

Placenta previa: obstetric risk factors and pregnancy outcome.

OBJECTIVE: To determine the incidence, obstetric risk factors and perinatal outcome of placenta previa. STUDY DESIGN: All singleton deliveries at our institution between 1990 and 1998 complicated with placenta previa were compared with those without placenta previa. RESULTS: Placenta previa complicated 0.38% (n = 298) of all singleton deliveries (n = 78 524). A back-step multiple logistic regression model found the following factors to be independently correlated with the occurrence of placenta previa: maternal age above 40 years (OR 3.1, 95% CI 2.0-4.9), infertility treatments (OR 3.1, 95% CI 1.8-5.6), a previous Cesarean section (OR 1.8, 95% CI 1.4-2.4), a history of habitual abortions (OR 1.3, 95% CI 1.3-2.7) and Jewish ethnicity (OR 1.3, 95% CI 1.1-1.8). Pregnancies complicated with placenta previa had significantly higher rates of second-trimester bleeding (OR 156.0, 95% CI 87.2-277.5), pathological presentations (OR 7.6, 95% CI 5.7-10.1), abruptio placentae (OR 13.1, 95% CI 8.2-20.7), congenital malformations (OR 2.6, 95% CI 1.5-4.2), perinatal mortality (OR 2.6, 95% CI 1.1-5.6), Cesarean delivery (OR 57.4, 95% CI 40.7-81.4), Apgar scores at 5 min lower than 7 (OR 4.4, 95% CI 2.3-8.3), placenta accreta (OR 3.6, 95% CI 1.1-9.9) postpartum hemorrhage (OR 3.8, 95% CI 1.2-10.5), postpartum anemia (OR 5.5, 95% CI 4.4-6.9) and delayed maternal and infant discharge from the hospital (OR 10.9, 95% CI 7.3-16.1) as compared to pregnancies without placenta previa. In a multivariable analysis investigating risk factors for perinatal mortality, the following were found to be independent significant factors: congenital malformations, placental abruption, pathological presentations and preterm delivery. In contrast, placenta previa and Cesarean section were found to be protective factors against the occurrence of perinatal mortality while controlling for confounders. CONCLUSION: Although an abnormal implantation per se was not an independent risk factor for perinatal mortality, placenta previa should be considered as a marker for possible obstetric complications. Hence, the detection of placenta previa should encourage a careful evaluation with timely delivery in order to reduce the associated maternal and perinatal complications.