Discover the most talked about and latest scientific content & concepts.

Concept: Placenta praevia


During cesarean delivery in patients with placenta previa, hemorrhaging after removal of the placenta is often challenging. In this condition, the extraordinarily high concentration of tissue factor at the placenta site may constitute a principal of treatment as it activates coagulation very effectively. The presumption, however, is that tissue factor is bound to activated factor VII (FVIIa).

Concepts: Placental abruption, Obstetrics, Factor VII, Caesarean section, Placenta praevia, Placenta accreta, Childbirth


Placenta accreta (an abnormally adherent placenta) is one of the two leading causes of peripartum hemorrhage and the most common indication for peripartum hysterectomy. Placenta accreta may be associated with significant maternal hemorrhage at delivery owing to the incomplete placental separation. When placenta accreta is diagnosed before delivery, a multidisciplinary approach may improve patient outcome.

Concepts: Obstetrics, Trophoblast, Placenta praevia, Hysterectomy, Childbirth, Placenta accreta, Caesarean section, Placenta


OBJECTIVE: To evaluate the risk of placenta praevia accreta following primary (first) elective or primary emergency caesarean section in a pregnancy complicated by placenta praevia. DESIGN: Retrospective matched case-control study, employing variable matching. SETTING: Tertiary referral centre between 1993 and 2008. POPULATION: Sixty-five cases and 102 controls were used for the analysis from a total of 82 667 births during the study period. METHODS: Relevant data were abstracted from clinical records. Matching of cases with controls was based on co-existing placenta praevia, number of previous caesarean sections, and age, with one or two controls per case. Results are presented as odds ratios (ORs) with 95% confidence intervals (95% CIs). MAIN OUTCOME MEASURES: Placenta accreta in a pregnancy complicated by placenta praevia following a primary elective or emergency caesarean section, and morbidity associated with pregnancies complicated by placenta accreta. RESULTS: Significantly more cases than controls had an elective caesarean section for their primary caesarean delivery (46.2 versus 18.6%; P < 0.001). There were no differences between groups for previous pregnancy loss, uterine surgery, and vaginal delivery, before or after the primary caesarean section. Compared with primary emergency caesarean section, primary elective caesarean section significantly increased the risk of placenta accreta in a subsequent pregnancy in the presence of placenta praevia (OR 3.00; 95% CI 1.47-6.12; P = 0.025). CONCLUSIONS: Our results suggest that women with a primary elective caesarean section without labour are more likely, compared with those undergoing primary emergency caesarean section with labour, to develop an accreta in a subsequent pregnancy with placenta praevia.

Concepts: Placental abruption, Epidural, Caesarean delivery on maternal request, Placenta praevia, Placenta accreta, Caesarean section, Obstetrics, Childbirth


Objective  To estimate the incidence of multiple repeat caesarean section (MRCS) (five or more) in the UK and to describe the outcomes for women and their babies relative to women having fewer repeat caesarean sections. Design  A national population-based prospective cohort study using the UK Obstetric Surveillance System (UKOSS). Setting  All UK hospitals with consultant-led maternity units. Population  Ninety-four women having their fifth or greater MRCS between January 2009 and December 2009, and 175 comparison women having their second to fourth caesarean section. Methods  Prospective cohort and comparison identification through the UKOSS monthly mailing system. Main outcome measures  Incidence, maternal and neonatal complications. Relative risk, unadjusted (OR) and adjusted (aOR) odds ratio estimates. Results  The estimated UK incidence of MRCS was 1.20 per 10 000 maternities [95% confidence interval (CI), 0.97-1.47]. Women with MRCS had significantly more major obstetric haemorrhages (>1500 ml) (aOR, 18.6; 95% CI, 3.89-88.8), visceral damage (aOR, 17.6; 95% CI, 1.85-167.1) and critical care admissions (aOR, 15.5; 95% CI, 3.16-76.0), than women with lower order repeat caesarean sections. These risks were greatest in the 18% of women with MRCS who also had placenta praevia or accreta. Neonates of mothers having MRCS were significantly more likely to be born prior to 37 weeks of gestation (OR, 6.15; 95% CI, 2.56-15.78) and therefore had higher rates of complications and admissions. Conclusions  MRCS is associated with greater maternal and neonatal morbidity than fewer caesarean sections. The associated maternal morbidity is largely secondary to placenta praevia and accreta, whereas higher rates of preterm delivery are most likely a response to antepartum haemorrhage.

Concepts: Epidemiology, Placental abruption, Relative risk, Caesarean section, Placenta praevia, Placenta accreta, Obstetrics, Childbirth


To compare the difference in maternal outcomes between early and late use of transverse annular compression sutures (TACS) during cesarean delivery among women with complete placenta previa (CPP).

Concepts: Epidural, Placenta, Placental abruption, Obstetrics, Caesarean section, Placenta accreta, Placenta praevia, Childbirth


BACKGROUND: To determine whether patients with placenta previa who delivered preterm have an increased risk for recurrent spontaneous preterm birth. METHODS: This retrospective population based cohort study included patients who delivered after a primary cesarean section (n = 9983). The rate of placenta previa, its recurrence, and the risk for recurrent preterm birth were determined. RESULTS: Patients who had a placenta previa at the primary CS pregnancy had an increased risk for its recurrence [crude OR of 2.65 (95 % CI 1.3-5.5)]. The rate of preterm birth in patients with placenta previa in the primary CS pregnancy was 55.9 %; and these patients had a higher rate of recurrent preterm delivery than the rest of the study population (p < .001). Among patients with placenta previa in the primary CS pregnancy, those who delivered preterm had a higher rate of recurrent spontaneous preterm birth regardless of the location of their placenta in the subsequent delivery [OR 3.09 (95 % CI 2.1-4.6)]. In comparison to all patients with who had a primary cesarean section, patients who had placenta previa and delivered preterm had an independent increased risk for recurrent preterm birth [OR of 3.6 (95 % CI 1.52-8.51)]. CONCLUSIONS: Women with placenta previa, who deliver preterm, especially before 34 weeks of gestation, are at increased risk for recurrent spontaneous preterm birth regardless to the site of placental implantation in the subsequent pregnancy. Thus, strict follow up by high risk pregnancies specialist is recommended.

Concepts: Prenatal development, Embryo, Placenta, Caesarean section, Placenta praevia, Placenta accreta, Obstetrics, Childbirth


OBJECTIVE: To evaluate characteristics of placenta accreta (PA) in patients without previous cesarean section. MATERIAL AND METHODS: Retrospective cohort study from December 1993 to April 2010 in two departments of obstetrics in university hospitals, Marseille, France. Comparison of clinical characteristics, circumstances of diagnosis, maternal morbidity and treatment was performed between PA diagnosed in patients with (n=63) and without prior cesarean section (n=35). RESULTS: In group of patients without previous caesarean section, rate of placenta praevia, and antenatal diagnosis were lower (16/35 [46 %] vs. 44/63 [70 %], [P: 0.02]) and (4/35 [11 %] vs. 28/63 [44 %], [P<0.001]) and rate of pregnancies obtained by IVF was higher (5/35 [15 %] vs. 2/63 [3 %], [P=0.05]). In this group, no hysterectomy was performed but risk of uterus necrosis following embolization was increased (3/35 [8.6 %] patients vs. 0/63 patients [P: 0.02]). CONCLUSIONS: Patients without previous caesarean section have specific characteristics in terms of risk factor and of management.

Concepts: Placental abruption, Pregnancy, Hysterectomy, Childbirth, Placenta praevia, Caesarean section, Placenta accreta, Obstetrics


This month, we focus on current research in placenta accreta. Dr. Lorenz discusses five recent publications, and each is concluded with a “bottom line” that is the take-home message. The complete reference for each can be found in on this page, along with direct links to the abstracts.

Concepts: Trophoblast, Placenta praevia, Placenta, Placenta accreta


Abnormal placental invasion can result in major obstetric haemorrhage during delivery. The most important risk factors are the following: previous caesarean delivery, placenta praevia maternal age over 35, smoking, previous myomectomy, dilatation and curettage. When placenta accreta is suspected on ultrasound, an RMI can complete the diagnostic. Therefore, patients must be managed, as far as possible, in a reference centre, by a trained medical team. Birth must be planned in order to decrease complications rate. Treatment can consist in radical management (caesarean-hysterectomy) or conservative management (preservation of both uterus and placenta). Conservative management allows patients to keep fertility but can also decrease blood loss during delivery. Side effects of this therapy are secondary haemorrhage, sepsis, long-term follow-up and vaginal loss. There are few studies describing fertility after conservative management, but it seems to be a secure treatment for future pregnancies. Embolization can be a very useful, already demonstrated, help when massive haemorrhage occurs. Management of placenta accreta is multidisciplinary and patients must be informed of all options. Treatment is decided regarding history of the patients, operative findings and peri-partum blood loss.

Concepts: Hysterectomy, Fetus, Placenta, Caesarean section, Placenta praevia, Obstetrics, Placenta accreta, Childbirth


We present a series of two cases complicated by uterine rupture following termination of pregnancy (TOP) in the 1st and 2nd trimesters using misoprostol in women with caesarean section scar. Current literature and practise have also been reviewed on ruptured uterus in women with caesarean section scar undergoing TOP using misoprostol; the diagnosis of adherent placenta in the 1st and 2nd trimesters in women with previous caesarean uterine scar; and likely implications of a ruptured uterus.

Concepts: Pregnancy, Caesarean section, Fetus, Placenta praevia, Placenta accreta, Hysterectomy, Obstetrics, Childbirth