[Fewer caesarean sections for breech presentation following external cephalic version according to a protocol in a special office visit]. / Minder keizersneden wegens stuitligging dankzij geprotocolleerde uitwendige versie in een speciaal spreekuur.

OBJECTIVE: Identification of determinants affecting the outcome of external cephalic version (ECV) in breech presentation, and investigation of the impact of ECV--performed according to a standardized protocol in an outpatient clinic--on the mode of delivery. DESIGN: Retrospective analysis. METHOD: In 2003 a standardized protocol of ECV was developed in the outpatient clinic for obstetrics of the Catharina Hospital in Eindhoven, the Netherlands; it was tested in 'version office visits'. Obstetric characteristics of all pregnant women who underwent attempts of ECV in the clinic from January 2004 until June 2006 during these sessions, and the subsequent births, were analysed. 85% of all ECVs were performed by the same hospital midwife and gynaecologist, in accordance with the protocol. RESULTS: ECV was successful in 96 of 209 pregnant women (46%). In 1 pregnant woman an emergency caesarean section was performed after ECV because of partial abruptio placentae. Nulliparity, incomplete breech presentation and low birth weight of the baby were associated with a lower success rate of ECV in this study. In the group with a successful ECV the percentage of caesarean deliveries was substantially lower (9 versus 83%; odds ratio: 0.21; 95% CI: 0.09-0.51). CONCLUSION: A regular team consisting of a hospital midwife and a gynaecologist working according to a standardized protocol for ECV in a case of breech presentation proved successful: the number of term breech presentations substantially diminished and therefore the percentage of caesarean sections was lower in the group in which ECV had been successful. This could have considerable impact on health care in the Netherlands in terms of reduced maternal morbidity and cost savings.

The regulation of pollen tube growth in Douglas-fir following high doses of ionizing radiation.

Acute irradiation of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) pollen by X-rays enhances pollen tube elongation. To determine whether this effect was due to physical damage of the pollen membranes or to metabolic processes, irradiated and control pollen were grown under conditions of anoxia. Thus, it was determined that physical damage only could be of minor importance. As parameters for metabolic processes RNA- and protein synthesis were studied. The only difference between irradiated and control pollen with respect to RNA synthesis was the time at which it started. Protein synthesis in vitro revealed that polyribosomes from irradiated pollen were more active than those from control pollen at lower concentrations. These results were confirmed by in ovo experiments with both polysomal preparations. The results indicate that X-ray irradiation is interfering with the main regulatory mechanism of pollen tube growth, which is de- and re-masking of, mainly, presynthesized mRNA.