No abstract

The aim of this study was to determine if nitric oxide (NO) production and nitric oxide synthase (NOS) isoforms change within the uterus and cervix during pregnancy and labour either at term or preterm. NO production was compared in the rat uterus and cervix of non-pregnant and pregnant rats on days 18-22 prior to labour, day 22 during delivery, 1 day post-partum and after treatment with either 10 mg onapristone or progesterone. Uterine NO synthesis, reflected in nitrite production, increased during gestation (194.2 +/- 22.6 nmol/g on day 19) compared with the non-pregnant state (76.2 +/- 18.4 nmol/g, P < 0.05) and decreased during term labour and post-partum. Furthermore, injection of lipopolysaccharide (LPS) (100 micrograms/rat i.p.) on day 20 of gestation resulted in a significant increase in NO synthesis after 6 h. Conversely, cervical NO synthesis and nitrite production was low in the non-pregnant (65.1 +/- 9.2 nmol/g) and pregnant animals on days 18-22 of gestation (53.2 +/- 9.0 nmol/g on day 22, P > 0.05), but markedly increased during term labour (139 +/- 28.6 nmol/g, P < 0.05). Treatment with the antiprogestin onapristone suppressed uterine NO production and increased cervical production while continuous administration of progesterone from day 19 had the opposite effect. LPS produced a significant increase in cervical NO production in both the pregnant (8-fold) and non-pregnant (4-fold) states. All three known NOS isoforms (i.e., iNOS, nNOS and eNOS) were detected in the cervical samples but only two were present in the uterus (iNOs and eNOS). An increase in the presence of iNOS occurred during labour at term compared with cervices collected from day 19. This was contrary to the measurements of the isoform in the uterus. Also, there was a similar increase of nNOS in the cervix during labour. This isoform seemed absent in the uterus during gestation. No significant changes occurred in the abundance of eNOS in the cervix during labour at term compared with day 19. During preterm labour after onapristone, iNOS concentrations increased significantly in the cervix. In order to examine whether the NO pathway plays a role in cervical ripening, the effects of the nitric oxide synthesis inhibitor L-nitro-arginine methylester (L-NAME) on the duration of delivery and on cervical extensibility were also investigated. The duration of delivery was significantly prolonged in L-NAME-treated rats compared with the control group (2.4-fold). Moreover, cervical extensibility decreased significantly (1.7-fold) after in-vitro incubation with L-NAME (P < 0.005). We conclude that the NO system may have an active role in the cascade of processes involved in preparing the uterus and cervix for parturition.

No abstract

No abstract

No abstract

ObjectiveTo understand current gestational weight gain (GWG) counselling practices of healthcare providers, and the relationships between practices, knowledge and attitudes.DesignConcurrent mixed methods with data integration: cross-sectional survey and semistructured interviews.ParticipantsPrenatal healthcare providers in Canada: general practitioners, obstetricians, midwives, nurse practitioners and registered nurses in primary care settings.ResultsTypically, GWG information was provided early in pregnancy, but not discussed again unless there was a concern. Few routinely provided women with individualised GWG advice (21%), rate of GWG (16%) or discussed the risks of inappropriate GWG to mother and baby (20% and 19%). More routinely discussed physical activity (46%) and food requirements (28%); midwives did these two activities more frequently than all other disciplines (P<0.001). Midwives interviewed noted a focus on overall wellness instead of weight, and had longer appointment times which allowed them to provide more in-depth counselling. Regression results identified that the higher priority level that healthcare providers place on GWG, the more likely they were to report providing GWG advice and discussing risks of GWG outside recommendations (β=0.71, P<0.001) and discussing physical activity and food requirements (β=0.341, P<0.001). Interview data linked the priority level of GWG to length of appointments, financial compensation methods for healthcare providers and the midwifery versus medical model of care.ConclusionsInterventions for healthcare providers to enhance GWG counselling practices should consider the range of factors that influence the priority level healthcare providers place on GWG counselling.

No abstract

No abstract