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

The association between of placenta previa and congenital abnormalities: a systematic review and network meta-analysis

BACKGROUND

Congenital abnormalities, as one of the fetal complications of placenta previa, may cause health problems or disability of the child throughout life. This study aimed to determine the relationship between placenta previa and congenital abnormalities.

METHODS

Potential articles were retrieved from three electronic databases (PubMed/Medline, Scopus, and Web of Sciences) up to 21 May 2023 without limit of time and language. A random effect model was applied for meta-analysis. The heterogeneity was calculated based on I2 statistic and Cochrane Q-test. All analyses were conducted at the significance level of 0.05 using STATA software, version 14. The quality assessment of the included studies was performed using the improved Newcastle-Ottawa Scale.

RESULTS

In the initial search, 829 articles were retrieved. Finally, according to the inclusion criteria, eight studies were analyzed in the meta-analysis. A significant association was reported between placenta previa and risk of congenital abnormalities based on crude form (OR = 1.81, 95% CI = 1.34 to 2.28) and adjusted studies (OR = 6.38, 95% CI = 1.47 to 11.30). The high heterogeneity was observed among the studies reported based on adjusted and crude form, respectively (I2 = 97.9%, P = 0.000) (I2 = 80.6%, P = 0.000). Therefore, publication bias was not observed among studies. Seven studies of the included studies were of high quality.

CONCLUSION

Our study provides evidence that there is a positive and significant association between placenta previa and congenital malformations, including all structural anomalies, chromosomal defects, and congenital hypothyroidisms. Therefore, monitoring congenital abnormalities in the fetus of a mother with placenta previa is necessary.

Bleeding-related outcomes of low-risk total placenta previa are equivalent to those of partial/marginal placenta previa

OBJECTIVE

To clarify whether "low-risk total PP" patients bleed more than partial/marginal PP patients.

MATERIALS AND METHODS

The retrospective cohort study was performed involving patients with PP between April 2006 and December 2018. The placental position was determined by ultrasound. From medical charts, the backgrounds as well as obstetric and neonatal outcomes of PP patients were retrieved.

RESULTS

This study included 349 patients with PP, which was classified into three types according to the distance between the placenta and internal ostium: total (n = 174), partial (n = 52), and marginal (n = 123) PP. In total PP patients, three factors (prior CS, anterior placenta, and placental lacunae on ultrasound) significantly increased blood loss at CS, the need for hysterectomy, homologous transfusion (≥10 U), and ICU admission. No significant difference was observed in bleeding-related poor outcomes (rate of blood loss ≥2000 mL, amount of homologous transfusion, need for hysterectomy, and ICU admission) between total PP patients without all three factors: "low-risk total PP patients" and partial/marginal PP patients (19.8 vs. 17.1%; p = 0.604, 3.7 vs. 1.1%; p = 0.330, 1.2 vs. 1.1%; p = 1.000, and 1.2 vs. 1.1%; p = 1.000, respectively).

CONCLUSION

Prior CS, anterior placenta, and placental lacunae on ultrasound were risk factors for a bleeding-related poor outcome in total PP patients. Total PP patients without these three factors showed the same bleeding-related poor outcome as partial/marginal PP patients.

Cervical length should be measured for women with placenta previa: cohort study

OBJECTIVES

To study the relevance between cervical length (CL) and different maternal/neonatal outcomes in pregnancies complicated with placenta previa/accreta.

METHODS

Three hundred twenty-eight women, who had medically free singleton live pregnancies with the diagnosis of placenta previa and/or accreta, were included and divided regarding their CL into two groups. Threatened preterm labor, maternal tocolysis, multiple gestations, polyhydramnios, ruptured fetal membranes, fetal complications, history of cervical conization, and the presence of cervical cerclage were the exclusion criteria. Demographic data, obstetric history, as well as, the courses of the complicated pregnancies were collected and statistically analyzed.

RESULTS

The short CL group had significantly less distance between the placenta and the internal cervical os (p-value < .001) Also, they showed more ultrasound parameters of complete placenta previa with anterior location (p-value < .001 and .003 respectively) and placental adherence (21.8 versus 41.1%). Women with short cervix had significantly higher rates of preterm birth, antepartum hemorrhage, emergency cesarean sections, intraoperative estimated blood loss, massive bleeding, prevalence of placental adherence and cesarean hysterectomy (p-value < .001 for the entire outcomes). Multivariable binary logistic regression showed that CL (<30 mm) was a significant independent risk factor in prediction of severe hemorrhage, PTB, emergency CS, placental adherence, cesarean hysterectomy (p-value < .001 for adverse maternal outcomes) and low cord Ph (p-value = .016).

CONCLUSIONS

Assessment of the cervical length could be a crucial step in the work-up and decision making for pregnancies complicated with abnormally situated and/or adherent placenta as it is strongly associated with a wide range of maternal and neonatal morbidities.

Using tocolysis in pregnant women with symptomatic placenta praevia does not significantly improve prenatal, perinatal, neonatal and maternal outcomes: a systematic review and meta-analysis

BACKGROUND

Placenta praevia refers to a placenta located in the lower segment of the uterus. This abnormal location predisposes the placenta to abnormal bleeding with an increased risk of premature labour. The merits of tocolytic drugs (tocolysis) to calm uterine contractions and prolong pregnancy in women with placenta praevia are uncertain.

OBJECTIVES

The primary objective is to determine the effects of tocolysis versus no tocolysis on pregnancy prolongation. Secondary objectives include to determining the effects of tocolysis versus no tocolysis on gestational age at delivery, maternal hospitalisations, recurrent vaginal bleeding, prematurity, admissions into neonatology, and perinatal deaths.

METHODS

We searched MEDLINE, EMBASE, The Cochrane Central Register of Controlled Trials, reference lists of pertinent articles and trial registries for randomised controlled trials comparing tocolysis to no tocolysis or placebo in patients with placenta praevia. Risk of bias and data extraction was done independently by two reviewers. We pooled data using a random-effects model. We used the GRADE system to assess the certainty of evidence for each outcome.

MAIN RESULTS

There is no significant difference in pregnancy prolongation with the use of tocolysis in cases of placenta praevia (mean difference [MD] 11.51 days; 95% CI, - 1.75, 24.76; 3 trials, 253 participants; low certainty evidence). Tocolysis has no significant effect on gestational age at delivery (MD 0.33 weeks [95% CI - 1.53, 2.19]: 2 trials, 169 participants, moderate certainty evidence), birthweight (MD 0.12 kg [95% CI - 0.26, 0.5 kg]: 2 trials, 169 participants, moderate certainty evidence), risk of premature delivery (risk ratio [RR] 1.04; 95% CI 0.56, 1.94): 2 trials, 169 participants, low certainty evidence), risk of repeat vaginal bleeding (RR 1.05 [95% CI 0.73, 1.51]: 2 trials, 169 participants, moderate certainty evidence). Tocolysis has no significant effect on the risk of perinatal death (risk difference [RD]: 0.00 [95% CI - 0.04, 0.03]: 2 trials, 169 women; low certainty evidence), number of days of maternal hospitalisation (MD 0.60 days [95% CI - 0.79, 1.99]: 1 trial, 109 women; low certainty evidence), risk of fetal admissions into neonatology (RR 1.30 [95% CI 0.80, 2.12]: 1 trial, 109 participants, low certainty evidence) and on the duration of stay in neonatology units (MD 0.70 days [95% CI - 5.26, 6.66]: 1 trial, 109 participants, low certainty evidence).

CONCLUSION

In women with symptomatic placenta praevia, there is no significant effect on pregnancy prolongation with the use of tocolysis. Tocolysis has no significant effect on other prenatal, perinatal, neonatal and maternal outcomes among women with symptomatic placenta praevia.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018091513.

Perceived risks and reasons to smoke cigarettes during pregnancy among Alaska native women

OBJECTIVE

The purpose of this study was to explore perceptions of the risks of smoking and reasons Alaska Native women give for smoking during pregnancy.

DESIGN

A total of 118 women (54 smokers, 64 non-smokers) enrolled in a biomarker study and completed a baseline interview asking about their concerns regarding tobacco use while pregnant and reasons why pregnant women might smoke during pregnancy. Responses were collapsed into six categories of perceived risks of smoking and eight categories of reasons to smoke during pregnancy.

RESULTS

The majority of both pregnant non-smokers and smokers (72.6% and 60.4%) agreed that smoking during pregnancy could negatively impact the health of their baby. However, non-smokers were more likely than smokers (77.4% vs. 58.5%) to view smoking during pregnancy as a risk factor for the baby's development (p = .029). Both non-smokers and smokers identified addiction as a reason for smoking during pregnancy (82.8% and 63%); however, non-smokers were more likely than smokers to state this was a reason for use (p = .015). Seventy-three percent of the entire sample reported a reason to smoke in pregnancy was to help manage negative affect.

CONCLUSION

Results from this work may be helpful in advancing research by identifying targets for intervention specific to Alaska Native women receiving prenatal care in Anchorage, Alaska.

Placental histopathology lesions and pregnancy outcome in pregnancies complicated with symptomatic vs. non-symptomatic placenta previa

BACKGROUND

The mechanisms involved in bleeding in cases of placenta previa (PP) and the effect on pregnancy outcome is unclear.

OBJECTIVES

We aimed to compare pregnancy outcome and placental histopathology in pregnancies complicated with symptomatic (bleeding) vs. non-symptomatic PP, and to study the effects of the co-existence of histopathological retro-placental hemorrhage (RPH) in cases of symptomatic PP on neonatal and maternal outcomes.

STUDY DESIGN

Labor and maternal characteristics, neonatal outcome and placental histopathology lesions of pregnancies with PP, delivered between 24 and 42weeks, during 2009-2015, were reviewed. Results were compared between PP who had elective cesarean delivery (CD) (previa group) and PP with bleeding necessitating emergent CD (symptomatic previa group). Placental lesions were classified to lesions consistent with maternal malperfusion or fetal thrombo-occlusive disease (vascular and villous changes), and inflammatory lesions.

RESULTS

Compared to the previa group (n=63), the symptomatic previa group (n=74) was characterized by older patients (p<0.001), higher rate of smokers (p=0.005), thrombophilia (p=0.038), and preterm deliveries (p<0.001). Placentas within the symptomatic previa group were smaller, with higher rates of weight<10th% (p=0.02), RPH (p<0.001) and villous changes related to maternal malperfusion (p=0.023). As compared to symptomatic PP without RPH, co-existence of RPH was associated with higher rate of adverse neonatal outcome (p<0.001) and maternal blood transfusion (p=0.02). On multivariate regression analysis, composite adverse neonatal outcome was found to be dependent on coexisting RPH (OR=2.8, 95%CI 1.2-11.7, p=0.03), and low gestational age (OR=3.1, 95%CI 1.6-4.9, p=0.02).

CONCLUSIONS

Symptomatic placenta previa is associated with increased placental malperfusion lesions suggesting an association of maternal malperfusion with abnormal placental separation. The coexisting finding of RPH with symptomatic placenta previa can be seen as a marker for more extensive/severe placental separation, hence the association with maternal transfusion requirements and poorer fetal outcome.

A late-preterm, early-term stratified analysis of neonatal outcomes by gestational age in placenta previa: defining the optimal timing for delivery

OBJECTIVE

Though no official guidelines address the issue of the optimal timing of delivery in placenta previa, common practice is to conduct delivery between 36 and 37 weeks gestation. Given the rising concerns regarding unnecessary premature deliveries, the objective of this study was to compare neonatal outcomes among pregnancies complicated by placenta previa delivered at the late-preterm period (35, 36 weeks) relative to the early-term period (37 and 38 weeks).

METHODS

We conducted a retrospective, population-based, cohort study using the CDC’s Linked Birth-Infant Death data files from the U.S. for the year 2004. We stratified the cohort according to gestational age and placenta previa status. Using 38 weeks gestation as reference controls, the effect of delivery in a pregnancy with placenta previa at 35, 36 and 37 weeks gestation on the risk of several neonatal outcomes was estimated using logistic regression analysis, adjusting for relevant confounders.

RESULTS

We analyzed a total of 4 118 956 births, of which 5675 (0.1%) met inclusion criteria. Late-preterm delivery was associated with lower birthweight and increased adequacy of care. Relative to neonates born at 38 weeks, birth at 35, 36 and 37 weeks was associated with no greater odds of meconium passage, fetal distress, fetal anemia, neonatal seizures, increased ventilator needs, or infant death at 1 year. However, odds of 5-min APGAR scores <7 were greater at 35 and 36 weeks (aOR [95% CI]): 3.33 [1.71-6.47] and 2.17 [1.11-4.22], respectively; as were odds of NICU admission rates: 2.25 [2.01-2.50] and 1.57 [1.38-1.76], respectively. Conclusions: Barring maternal indications, early-term delivery in placenta previa is associated with fewer complications and no greater risk than late-preterm delivery. This information may be helpful in the development of future guidelines, which are currently needed to guide the management of these pregnancies.

Placenta previa and long-term morbidity of the term offspring

OBJECTIVE

The long-term impact of placenta previa on term infants is unknown. We aimed to investigate whether abnormal placentation increases the risk for long-term morbidity of the term offspring.

STUDY DESIGN

A population-based cohort study compared the incidence of long-term hospitalizations up to the age of 18 due to cardiovascular, endocrine, neurological, hematological, respiratory and urinary morbidity of children born at term in pregnancies diagnosed with placenta previa and those without. Deliveries occurred between the years 1991-2013 in a tertiary medical center. Multiple pregnancies, and fetal congenital malformations were excluded. Kaplan-Meier survival curves were used to compare cumulative morbidity incidence over time. A multivariable generalized estimating equation (GEE) logistic regression model analysis was used to control for confounders and for maternal clusters.

RESULTS

During the study period 233,123 term deliveries met the inclusion criteria; 0.2% (n=502) of the children were born to mothers with placenta previa. During the follow-up period, children born to mothers with placenta previa did not have an increased risk for long-term cardiovascular, endocrine, hematological, neurological, respiratory, and urinary morbidity.

CONCLUSION

Term offsprings of mothers diagnosed with placenta previa do not appear to be at an increased risk for long-term morbidity up to the age of 18.

Placenta previa and immediate outcome of the term offspring

PURPOSE

Immediate neonatal outcome in pregnancies complicated by placenta previa is largely dependent on gestational age. We aimed to investigate whether placenta previa increases the risk for perinatal mortality and immediate morbidity of the offspring born at term.

METHODS

A population-based cohort study included all singleton pregnancies, with and without placenta previa, delivered at term. Maternal and pregnancy characteristics as well as immediate neonatal morbidity and mortality were compared. Deliveries occurred between the years 1991-2013 in a tertiary medical center. Multiple pregnancies, and fetal congenital malformations were excluded.

RESULTS

During the study period 233,123 consecutive term deliveries met the inclusion criteria; 0.2 % of the babies were born to mothers diagnosed with placenta previa. Women with placenta previa were significantly older and more likely to have had a previous cesarean section. Pregnancies were more likely to be complicated with pathological presentations and cesarean hysterectomies. Babies born at term following pregnancies with placenta previa were more likely to weigh less than 2500 g (OR 2.78 CI 1.9-3.9, p < 0.001). However, 5 min Apgar score and perinatal mortality rates were comparable between the groups. Neonatal outcomes remained comparable between the groups in a sub-analysis of cesarean deliveries only.

CONCLUSION

Although placenta previa pregnancies involve higher maternal morbidity rates, term offsprings are not at an increased risk for immediate adverse outcome.

Placenta previa associated with severe bleeding leading to hospitalization and delivery: a retrospective population-based cohort study

INTRODUCTION

The aim of our study was to compare maternal and neonatal outcomes in women with placenta previa complicated with severe bleeding leading to hospitalization until delivery versus those without severe bleeding episodes.

METHODS

This is a population-based retrospective cohort study including all pregnant women with placenta previa who delivered at our medical center in the study period, divided into the following groups: 1) women with severe bleeding leading to hospitalization resulting with delivery (n = 32); 2) patients with placenta previa without severe bleeding episodes (n = 1217).

RESULTS

Out of all women with placenta previa who delivered at our medical center, 2.6% (32/1249) had an episode of severe bleeding leading to hospitalization and resulting with delivery. The rate of anemia was lower (43.8% versus 63.7%, p = 0.02) while the need for blood transfusion higher (37.5% versus 21.1%, p = 0.03) in the study group. The rate of cesarean sections was significantly different between the groups, and a logistic regression model was constructed in order to find independent risk factors for cesarean section in our patients.

CONCLUSION

To the best of our knowledge, this is the first study to evaluate the impact of severe bleeding on the outcome of pregnancies complicated with placenta previa. Our study demonstrates that, in women with placenta previa, severe bleeding does not lead to increased adverse maternal or neonatal outcomes.

Frequency of placenta previa in previously scarred and non scarred uterus

Objective:

To determine the frequency of placenta Previa in patients coming to a tertiary care unit with previously scarred and non-scarred uterus.

Methods:

A descriptive cross sectional study was carried on 114 cases who underwent caesarean sections (37 cases out of 645 cases with non scarred uterus and 77 cases from 721 cases with scarred uterus) in the department of obstetrics and gynecology Lady Willingdon Hospital from January 2008– December 2011.

Results:

Most patients (47.36%) were between 26-30 years age group, presented with gestational age between 36-40 weeks (70.17%), were mostly G2-4, while frequency of placenta Previa in non-scarred uterus was 32.45% (37 cases), and frequency in previously scarred uterus was 67.54% (77 cases). Major degree Previa was found in 88 cases (77.19%). There were 5.70% cases of placenta Previa from non-scarred uteruses and 10.67% cases of placenta Previa (10.67%) from already scarred uteruses. Stratification revealed a higher trend of the morbidity with the increase in number of previous caesarean sections.

Conclusion:

A significantly higher frequency of placenta Previa was found among patients coming to a tertiary care hospital with previously scarred uterus.

Consecutive cervical length measurements as a predictor of preterm cesarean section in complete placenta previa

BACKGROUND

To evaluate whether consecutive cervical length measurements can predict preterm cesarean section in women with complete placenta previa.

METHODS

Seventy-one women with complete placenta previa were retrospectively categorized into women who delivered preterm due to massive hemorrhage (the preterm cesarean section group, n = 28) and those delivered at term (the control group, n = 43). Maternal characteristics, delivery outcomes, and cervical lengths serially measured at least every 2 weeks from 24 weeks' gestation until delivery were compared. The relationship between cervical length and preterm cesarean section was analyzed.

RESULTS

Cervical length gradually decreased with advancing gestational age. After 26 weeks' gestation, this decrease was significantly more rapid in the preterm cesarean section group. Cervical length before cesarean section in the preterm cesarean section group was significantly shorter than that in the control group. Just before cesarean section, 71.4% of the preterm cesarean section group presented with cervical lengths of ≤35 mm, whereas only 34.9% of the control group had cervical lengths of ≤35 mm (odds ratio 4.67, 95% confidence interval 1.66-13.10, p = 0.006).

CONCLUSIONS

In women with complete placenta previa, decrease in cervical length to ≤35 mm was associated with increased risk of preterm cesarean section due to massive hemorrhage.

Placenta previa and the risk of delivering a small-for-gestational-age newborn

OBJECTIVE

To evaluate whether there is an association between placenta previa and delivery of a small-for-gestational-age (SGA) newborn and to quantify the contribution of individual risk factors for SGA that are associated with placenta previa stratified by maternal parity.

METHODS

A cross-sectional study using the Finnish Medical Birth Register during 2000-2010. All singleton births (N=596,562) were included; major congenital anomalies were excluded. An association between SGA (less than 2 standard deviations below the mean) and placenta previa was modeled by parity-specific unadjusted and adjusted statistical models.

RESULTS

Placenta previa complicated 625 of 249,476 singleton births among nulliparous women (2.50/1,000) and 915 of 347,086 singleton births among multiparous women (2.64/1,000). Among nulliparous women, the most common risk factor for placenta previa was in vitro fertilization; placenta previa was not associated with an increased prevalence of SGA controlling for maternal age, smoking, in vitro fertilization, socioeconomic status, and preeclampsia (adjusted odds ratio [OR] 0.81, 95% confidence interval [CI] 0.57-1.17). Among multiparous women, placenta previa was associated with a twofold increased risk of SGA controlling for maternal age, parity, prior preterm birth, prior caesarean delivery, prior SGA newborn, prior preeclampsia, smoking, in vitro fertilization, socioeconomic status, and preeclampsia (adjusted OR 2.08, 95% CI 1.50-2.89). Furthermore, only one-fourth of the association between SGA and placenta previa could be explained by controlling for risk factors clustering with placenta previa among multiparous women.

CONCLUSION

Placenta previa is associated with impaired fetal growth in multiparous but not nulliparous women.

LEVEL OF EVIDENCE

II.

Predictors of perinatal mortality associated with placenta previa and placental abruption: an experience from a low income country

A retrospective cohort study design was used to assess predictors of perinatal mortality in women with placenta previa and abruption between January 2006 and December 2011. Four hundred thirty-two women (253 with placenta previa and 179 with placental abruption) were eligible for analysis. Binary logistic regression, Kaplan-Meier survival curve, and receiver operating characteristic (ROC) curve were used. On admission, 77% of the women were anaemic (<12 gm/dL) with mean haemoglobin level of 9.0 ± 3.0 gm/dL. The proportion of overall severe anaemia increased from about 28% on admission to 41% at discharge. There were 50% perinatal deaths (neonatal deaths of less than seven days of age and fetal deaths after 28 weeks of gestation). In the adjusted odds ratios, lengthy delay in accessing hospital care, prematurity, anaemia in the mothers, and male foetuses were independent predictors of perinatal mortality. The haemoglobin level at admission was more sensitive and more specific than prematurity in the prediction of perinatal mortality. The proportion of severe anaemia and perinatal mortality was probably one of the highest in the world.

Type and location of placenta previa affect preterm delivery risk related to antepartum hemorrhage

PURPOSE

To evaluate whether type and location of placenta previa affect risk of antepartum hemorrhage-related preterm delivery.

METHODS

We retrospectively studied 162 women with singleton pregnancies presenting placenta previa. Through observation using transvaginal ultrasound the women were categorized into complete or incomplete placenta previa, and then assigned to anterior and posterior groups. Complete placenta previa was defined as a placenta that completely covered the internal cervical os, with the placental margin >2 cm from the os. Incomplete placenta previa comprised marginal placenta previa whose margin adjacent to the internal os and partial placenta previa which covered the os but the margin situated within 2 cm of the os. Maternal characteristics and perinatal outcomes in complete and incomplete placenta previa were compared, and the differences between the anterior and the posterior groups were evaluated.

RESULTS

Antepartum hemorrhage was more prevalent in women with complete placenta previa than in those with incomplete placenta previa (59.1% versus 17.6%), resulting in the higher incidence of preterm delivery in women with complete than in those with incomplete placenta previa [45.1% versus 8.8%; odds ratio (OR) 8.51; 95% confidence interval (CI) 3.59-20.18; p < 0.001]. In complete placenta previa, incidence of antepartum hemorrhage did not significantly differ between the anterior and the posterior groups. However, gestational age at bleeding onset was lower in the anterior group than in the posterior group, and the incidence of preterm delivery was higher in the anterior group than in the posterior group (76.2% versus 32.0%; OR 6.8; 95% CI 2.12-21.84; p = 0.002). In incomplete placenta previa, gestational age at delivery did not significantly differ between the anterior and posterior groups.

CONCLUSION

Obstetricians should be aware of the increased risk of preterm delivery related to antepartum hemorrhage in women with complete placenta previa, particularly when the placenta is located on the anterior wall.

Risk of placenta previa in second birth after first birth cesarean section: a population-based study and meta-analysis

BACKGROUND

OBJECTIVE

To compare the risk of placenta previa at second birth among women who had a cesarean section (CS) at first birth with women who delivered vaginally.

METHODS

Retrospective cohort study of 399,674 women who gave birth to a singleton first and second baby between April 2000 and February 2009 in England. Multiple logistic regression was used to adjust the estimates for maternal age, ethnicity, deprivation, placenta previa at first birth, inter-birth interval and pregnancy complications. In addition, we conducted a meta-analysis of the reported results in peer-reviewed articles since 1980.

RESULTS

The rate of placenta previa at second birth for women with vaginal first births was 4.4 per 1000 births, compared to 8.7 per 1000 births for women with CS at first birth. After adjustment, CS at first birth remained associated with an increased risk of placenta previa (odds ratio = 1.60; 95% CI 1.44 to 1.76). In the meta-analysis of 37 previously published studies from 21 countries, the overall pooled random effects odds ratio was 2.20 (95% CI 1.96-2.46). Our results from the current study is consistent with those of the meta-analysis as the pooled odds ratio for the six population-based cohort studies that analyzed second births only was 1.51 (95% CI 1.39-1.65).

CONCLUSIONS

There is an increased risk of placenta previa in the subsequent pregnancy after CS delivery at first birth, but the risk is lower than previously estimated. Given the placenta previa rate in England and the adjusted effect of previous CS, 359 deliveries by CS at first birth would result in one additional case of placenta previa in the next pregnancy.

Alcohol consumption during pregnancy and risk of placental abruption and placenta previa

The purpose of this study was to examine the association between prenatal alcohol consumption and the occurrence of placental abruption and placenta previa in a population-based sample. We used linked birth data files to conduct a retrospective cohort study of singleton deliveries in the state of Missouri during the period 1989 through 2005 (n = 1,221,310). The main outcomes of interest were placenta previa, placental abruption and a composite outcome defined as the occurrence of either or both lesions. Multivariate logistic regression was used to generate adjusted odd ratios, with non-drinking mothers as the referent category. Women who consumed alcohol during pregnancy had a 33% greater likelihood for placental abruption during pregnancy (adjusted odds ratio (OR), 95% confidence interval (CI) = 1.33 [1.16-1.54]). No association was observed between prenatal alcohol use and the risk of placenta previa. Alcohol consumption in pregnancy was positively related to the occurrence of either or both placental conditions (adjusted OR [95% CI] = 1.29 [1.14-1.45]). Mothers who consumed alcohol during pregnancy were at elevated risk of experiencing placental abruption, but not placenta previa. Our findings underscore the need for screening and behavioral counseling interventions to combat alcohol use by pregnant women and women of childbearing age.

Risk factors of neonatal anemia in placenta previa

OBJECTIVES

Placenta previa is a major cause of neonatal anemia. The purpose of this study was to elucidate the risk factors of neonatal anemia in placenta previa.

METHODS

The study was conducted on 158 placenta previa patients at 3 hospitals in affiliation with the Catholic Medical Center, Seoul, Korea from May 1999 through December 2009. The subjects were divided in to 2 groups: 47 placenta previa patients with neonatal anemia, and 113 placenta previa patients without neonatal anemia. The subjects' characteristics were compared. Logistic regression was used to control for confounding factors.

RESULTS

Anterior placental location (OR 2.48; 95% CI: 1.20-5.11) was an independent risk factor of neonatal anemia after controlling for potential confounders.

CONCLUSION

To manage neonatal anemia in placenta previa patients, obstetricians should do their best to detect placental location. Pediatricians should consider the high possibility of neonatal anemia in cases involving anterior placental location.

Management of women with major placenta praevia without haemorrhage: A questionnaire-based survey of Irish obstetricians

Our aim was to determine individual management of women with major placenta praevia without antepartum haemorrhage (APH) using a questionnaire-based study. Placenta praevia complicates one in 200 pregnancies. It is associated with maternal mortality of 0.03%. The maternal, fetal and neonatal morbidity and mortality are due to the complications of haemorrhage and prematurity. APH due to placenta praevia is unpredictable and this may explain the traditional inpatient approach to management. This approach may be justified in those with bleeding, it is questionable in those who have not bled. A total of 121 obstetricians replied (63%), to 192 questionnaires sent out. Of these, 48 obstetricians would admit all women with major placenta praevia without APH, while 69 would manage them on an outpatient basis. When asked whether or not they agreed with outpatient management, 21 agreed strongly, 51 tended to agree, 23 tended to disagree and 13 disagreed strongly. Over half of the obstetricians adopt an outpatient management approach.

Risk factors and pregnancy outcome in different types of placenta previa

OBJECTIVE

To compare risk factors and pregnancy outcome between different types of placenta previa (PP).

MATERIALS AND METHODS

We conducted a retrospective study of 306 women presenting with PP over a 10-year period from January 1996 to December 2005. Differences between women with major and minor PP regarding age, parity, history of Caesarean section, antepartum hemorrhage, preterm deliveries, placenta accreta, Caesarean hysterectomy, operative complications, and neonatal outcome were identified using Mann-Whitney U test, chi-square test, and multivariate logistic regression.

RESULTS

The overall incidence of PP was 0.73%. Major PP (complete or partial PP) occurred in 173 women (56.5%) and minor PP (marginal PP or low-lying placenta) in 133 women (43.5%). There were no differences between women with major and minor PP regarding age, parity, and previous miscarriages. After controlling for confounding factors, women with major PP showed a significantly higher incidence of antepartum hemorrhage (OR 3.18; 95% CI 1.58-6.4, P = 0.001), placenta accreta (OR 3.2; 95% CI 1.22-8.33, P = 0.017), and hysterectomy (OR 5.1; 95% CI 1.31-19.86, P = 0.019). Antepartum hemorrhage in women with PP was associated with premature delivery (OR 14.9; 95% CI 4.9-45.1, P < 0.001), more commonly in women with major PP. The only significant difference between women with major and minor PP regarding neonatal outcome was that major PP was associated with a higher incidence of admission to the neonatal intensive care unit (P = 0.014).

CONCLUSION

Complete or partial placenta previa is associated with higher morbidity than marginal placenta previa or low-lying placenta.

Healthy start program and feto-infant morbidity outcomes: evaluation of program effectiveness

OBJECTIVE

We evaluate the impact of the Healthy Start intervention program on feto-infant morbidity within a community setting.

METHODS

Prospective data from 2002 to 2007 within the ongoing Federally funded Healthy Start intervention project in Central Hillsborough County were merged with corresponding birth outcomes data from the Florida Department of Health. The impact of the project on the following feto-infant morbidity indices was assessed among service recipients: low birth weight (LBW), very low birth weight (VLBW), preterm, very preterm, small for gestational age (SGA) and a composite feto-infant morbidity outcome. Program effectiveness and impact were measured using odds ratios from logistic regression models and number needed to treat (NNT).

RESULTS

The risk for low birth weight (OR = 0.7; 95% CI = 0.5-1.0), preterm (OR = 0.7; 95% CI = 0.5-0.9) and the composite feto-infant morbidity outcome (OR = 0.8; 95% CI = 0.6-0.9) was reduced among service recipients (N = 536) as compared to non-recipients (N = 2,815). A clinically important level of risk reduction was also noted for very low birth weight (OR = 0.5; 95% CI = 0.2-1.1) and very preterm (OR = 0.6; 95% CI = 0.3-1.2) although these did not reach statistical significance. The adjusted NNT was lowest for the composite feto-infant morbidity outcome (18), preterm birth (21) and low birth weight (24), and highest for very preterm (86) and very low birth weight (74) events.

CONCLUSIONS

In a disadvantaged community setting, the Healthy Start intervention program was found to reduce the risk for very low birth weight and preterm births by about one-third.

Previous caesarean or vaginal delivery: which mode is a greater risk of perinatal death at the second delivery?

OBJECTIVE

To compare the risk of perinatal death after previous caesarean versus previous vaginal delivery, and pre-labour repeat caesarean versus trial of labour after previous caesarean.

STUDY DESIGN

Using the data of the Berlin Perinatal Registry from 1993 to 1999, 7556 second parous women with a previous caesarean delivery were compared with 55142 second parous women with a previous vaginal delivery, and those 1435 women with pre-labour repeat caesarean were compared with 6121 women with a trial of labour after previous caesarean delivery. The rates of perinatal death, stillbirth and intrapartum/neonatal death were analysed using multivariable logistic regression to adjust for confounding variables and obstetric history.

RESULTS

A previous caesarean delivery was associated with a 40% excess risk of perinatal death and a 52% excess risk of stillbirth (p<0.05); the risk of intrapartum/neonatal death was not significantly increased. There were no significantly higher rates of intrapartum/neonatal death and of stillbirth in women trying a vaginal birth versus pre-labour repeat caesarean. But in most cases of antepartum death, labour was induced for that reason.

CONCLUSION

Consulting women about caesarean delivery for maternal request, the increased risk of perinatal death in further pregnancies should be discussed. After a previous caesarean delivery, a careful screening for several risk factors is necessary before recommending a trial of labour.

Cervical varix as a cause of vaginal bleeding during pregnancy: prenatal diagnosis by color Doppler ultrasonography

Vaginal bleeding during pregnancy is a risk factor for adverse pregnancy outcome. Beyond 20 weeks of gestation, the most frequent causes of bleeding associated with maternal and perinatal morbidity and mortality are placenta previa and placental abruption. Cervical varix during pregnancy is a rare condition. To our knowledge, only six cases have been reported in the literature. Most of these cases were associated with preterm birth and high maternal morbidity. The optimal management and mode of delivery remain undetermined. We report a case of cervical varix diagnosed by transvaginal ultrasound at 21 weeks of gestation. The pregnancy was complicated by several episodes of vaginal bleeding and the patient delivered at 32 weeks. Color and power Doppler examination of the cervix played a key role in establishing the diagnosis.

General obstetrics: Vaginal birth after caesarean section versus elective repeat caesarean section: assessment of maternal downstream health outcomes

OBJECTIVE

To compare the maternal implications of strategies of vaginal birth after caesarean section (VBAC) attempt versus elective repeat caesarean section in women with one previous lower segment caesarean section.

DESIGN

Decision model.

POPULATION

Women with one prior low transverse caesarean section who are eligible for trial of labour.

METHODS

Two decision models were built: the first one applying to women planning only one more pregnancy, the second one applying to women planning two more pregnancies. Probability estimates for VBAC success rate and risks of uterine rupture, placenta praevia, placenta accreta and hysterectomy were extracted from the available literature.

MAIN OUTCOME MEASURES

Hysterectomy for uterine rupture, placenta accreta or other indications.

RESULTS

In the first model VBAC attempt led to a higher hysterectomy rate (267/100,000) compared with repeat caesarean section (187/100,000). However, in the second model a policy of elective repeat caesarean section led to higher cumulative hysterectomy rate: 1465/100,000 versus 907/100,000 for VBAC. The first model was robust to all but one variable in sensitivity analyses. The second model was robust to all variables in sensitivity analyses.

CONCLUSIONS

These results indicate that long term reproductive consequences of multiple caesarean sections should be considered when making policy decisions regarding the risk-benefit ratio of VBAC.

Perinatal Outcome of Pregnancies Complicated by Placenta Accreta

OBJECTIVE

The purpose of the study was to characterize the perinatal outcome of pregnancies complicated by placenta accreta.

METHODS

We conducted a case-control analysis of all deliveries between the years 1990 and 2000 that were complicated by placenta accreta. Perinatal variables included in the analysis were gestational age at delivery, birth weight, Apgar scores, and perinatal mortality. Statistical analysis was performed using both the unpaired and paired approach. P <.05 was considered significant.

RESULTS

The study encompassed 34,450 deliveries, from which 310 cases of placenta accreta were diagnosed (0.9%) and compared with 310 matched controls. In the pregnancies complicated by placenta accreta, we found a statistically significant increase in preterm deliveries (10.7% versus 1%, P <.001, odds ratio 12.1, 95% confidence interval 3.7-39.9) and small-for-gestational-age babies (27.3% versus 14%, P <.001, odds ratio 5.05, 95% confidence interval 1.46-3.28).

CONCLUSION

Pregnancies complicated by placenta accreta are at increased risk for perinatal adverse outcome. We speculate that these findings may arise from pathological implantation of the placenta, resulting in interference with normal fetal growth.