The increased total cesarean rates in the Nordic countries are explained by increased cesarean rates among nulliparous women, and by an increased percentage of women with previous cesarean. Meanwhile, induction rates on nulliparous increased significantly, but the impact on the total cesarean rate was unclear. The Robson classification facilitates benchmarking and targeting efforts for lowering the cesarean rates.

Objectives To determine if placental syncytiotrophoblast microvillous (STBM) membranes contain factors which could cause the maternal endothelial cell disturbance thought to be central to the pathophysiology of the maternal syndrome of pre‐eclampsia. Design STMB membranes isolated from pre‐eclamptic or normal placentae were added to cultures of endothelial cells and their effect on the proliferation (measured by 3H‐thymidine incorporation), viability (measured by 51Cr release) and growth as a monolayer of these cells was determined. Membranes prepared from red blood cells, and nonendothelial adherent and nonadherent cell lines were used as specificity controls. Subjects STBM membranes were isolated from the placentae of primigravid women, 10 having caesarean sections for breech presentations and 10 for pre‐eclampsia. Results STBM membranes from the placentae of normal and pre‐eclamptic women suppressed endothelial cell proliferation to a similar extent and disrupted the cell monolayer to form a honeycomb‐like pattern. This change in morphology was seen before significant endothelial cell death occurred. Red blood cell membranes had no effect on either endothelial cell proliferation, viability or monolayer integrity. Endothelial cells from human umbilical arteries and bovine adrenal capillaries were similarly suppressed, but comparable concentrations of STBM membranes had no effect on nonendothelial cell lines. Conclusions Syncytiotrophoblast microvillous membranes specifically interfered with endothelial cell growth in vitro. Our results demonstrate that there are trophoblast products which could cause the maternal syndrome of pre‐eclampsia through endothelial cell damage.

Raised levels of PAPP-A in preeclampsia confirm earlier reports. Activin A showed the highest increase over the controls and is thus likely to be a better serum marker for this pathology than the other markers that were tested.

Objective To investigate the hypothesis that, should there be an increase in deported syncytiotrophoblast microvillous membrane fragments in pre-eclampsia, it may cause maternal vascular endothelial dysfunction.Design Syncytiotrophoblast microvillous membrane (STBM) vesicles, prepared from normal term placentae, were perfused through small subcutaneous arteries isolated from fat biopsies obtained at caesarean section. Endothelial function of these arteries was studied by determining acetylcholineinduced relaxation after preconstriction with noradrenaline. As controls, physiological buffer or red blood cell membranes in physiological buffer were used and endothelial function similarly estimated. Transmission electron microscopy was performed on arteries after perfusion.Sample STBM vesicles, isolated from the placentae of three healthy women undergoing elective caesarean section for reasons unrelated to pre-eclampsia, were suspended in physiological buffer. Subcutaneous fat arteries were obtained from a separate group of 13 normotensive pregnant women, also undergoing elective caesarean section at term.Results Perfusion with red blood cell membranes or physiological buffer had no significant effect on the concentration dependent relaxation in arteries preconstricted with noradrenaline. However, after 2 h perfusion with STBM vesicles, arteries showed a significant reduction in relaxation to acetylcholine, indicative of altered endothelial function. Transmission electron microscopy of arteries perfused with STBM vesicles confirmed endothelial disruption.Conclusions STBM vesicle perfusion specifically altered the relaxation response of preconstricted maternal subcutaneous fat arteries to acetylcholine, suggesting an alteration in endothelial dependent relaxation. Deported microvilli may therefore be capable of producing endothelial cell damage and endothelial dysfimction observed in the maternal syndrome of pre-eclampsia.

Objectives Nitric oxide released from vascular endothelial cells is a potent vasodilator and inhibits platelet adhesion. It has been suggested that decreased nitric oxide production from dysfunctional endothelial cells is implicated in the pathophysiology of pre-eclampsia. In this study evidence was sought for abnormal production of nitric oxide in pre-eclamptic women.Participants Blood was collected from 20 women presenting with pre-eclampsia, from 20 matched healthy pregnant controls and from 12 nonpregnant women of childbearing age.Methods Serum nitrate, the stable end metabolite of nitric oxide, was measured by vanadium 111 chloride reduction and chemiluminescence.Results Sera fiom women with pre-eclampsia had significantly higher nitrate concentrations (mean 47.4 pmol/L [SD 13-61) compared with healthy pregnant (mean 31.2 pmol/L. [SD 9.141) and nonpregnant (mean 32.1 pmol/L [SD 10.01) controls.Conclusions These results do not support the hypothesis that decreased endothelial cell nitric oxide production may be important in the pathophysiology of pre-eclampsia. On the contrary, serum nitrate levels are increased which may reflect either increased production of nitric oxide from an unidentified source or decreased elimination through the kidneys.

Objective. To study the incidence, maternal characteristics and outcome of unplanned out-of-institution births (= unplanned births) in Norway. Design. Register-based cross-sectional study. Population. All births in Norway (n = 892 137) from 1999 to 2013 with gestational age ≥22 weeks. Methods. Analysis of data from the Medical Birth Registry of Norway from 1999 to 2013. Unplanned births (n = 6062) were compared with all other births (reference group). Results. The annual incidence rate of unplanned births was 6.8/1000 births and remained stable during the period of study. Young multiparous women residing in remote municipalities were at the highest risk of experiencing unplanned births. The unplanned birth group had higher perinatal mortality rate for the period, 11.4/1000 compared with 4.9/1000 for the reference group (incidence rate ratio 2.31, 95% confidence interval 1.82-2.93, p < 0.001). Annual perinatal mortality rate for unplanned births did not change significantly (p = 0.80) but declined on average by 3% per year in the reference group (p < 0.001). The unplanned birth group had a lower proportion of live births in all birthweight categories. Live born neonates with a birthweight of 750-999 g in the unplanned birth group had a more than five times higher mortality rate during the first week of life, compared with reference births in the same birthweight category. Conclusions. Unplanned births are associated with adverse outcome. Excessive mortality is possibly caused by reduced availability of necessary medical interventions for vulnerable newborns out-of-hospital.

Background Rising cesarean rates call for studies on which subgroups of women contribute to the rising rates, both in countries with high and low rates. This study investigated the cesarean rates and contributing groups in Iceland using the Robson 10‐group classification system. Methods This study included all births in Iceland from 1997 to 2015, identified from the Icelandic Medical Birth Registry (81 839). The Robson distribution, cesarean rate, and contribution of each Robson group were analyzed for each year, and the distribution of other outcomes was calculated for each Robson group. Results The overall cesarean rate in the population was 16.4%. Robson groups 1 (28.7%) and 3 (38.0%) (spontaneous term births) were the largest groups, and groups 2b (0.4%) and 4b (0.7%) (prelabor cesareans) were small. The cesarean rate in group 5 (prior cesarean) was 55.5%. Group 5 was the largest contributing group to the overall cesarean rate (31.2%), followed by groups 1 (17.1%) and 2a (11.0%). The size of groups 2a (RR 1.04 [95% CI 1.01‐1.08]) and 4a (RR 1.04 [95% CI 1.01‐1.07]) (induced labors) increased over time, whereas their cesarean rates were stable (group 2a: P = 0.08) or decreased (group 4a: RR 0.95 [95% CI 0.91‐0.98]). Conclusions In comparison with countries with high cesarean rates, the prelabor cesarean groups (singleton term pregnancies) in Iceland were small, and in women with a previous cesarean, the cesarean rate was low. The size of the labor induction group increased, yet the cesarean rate in this group did not increase.

This study adds to the growing body of evidence that suggests that planned home birth for low-risk women is as safe as planned hospital birth.