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PurposeThe purpose of this paper is to provide macromechanical insight into the fatigue behaviour of laser sintered parts and to understand the influence of the laser sintered surface structure on this behaviour.Design/methodology/approachA background on the technological maturity of manufacturing processes and the demand for structural and aesthetic properties of laser sintered plastic products is given. As the contribution of surface structure on part quality was the focus, laser sintered specimens with and without surface finishes, as well as injection moulded specimens were used. The latter simply served as a comparison and was not intended to qualify injection moulding. The study comprises the determination of short‐term tensile properties, the load increase method for investigating fracture and deformation behaviours, and fatigue crack propagation analysis.FindingsAccording to the test results, the contribution of laser sintered surface structures to relevant mechanical properties can be neglected. Under dynamic loading conditions, laser sintered specimens achieved a longer lifetime but showed less deformation capabilities in contrast to injection moulded specimens. In general, laser sintered specimens presented considerable resistance to crack initiation and propagation.Research limitations/implicationsBecause of the long‐term approach of the research, the number of tests conducted per lot was limited. Thus, the effects of different process settings and the reproducibility could not be fully analysed.Practical implicationsThe studied fatigue behaviour of laser sintered specimens has implications for the functional testing of parts or components, for the product and process design as well as for the general compatibility of laser sintering as a manufacturing technology of end‐customer products.Originality/valueThe value of this paper lies in the better understanding of deformation and fracture behaviours of laser sintered polymers.

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Public health information should emphasize that postponement of first birth could lead to involuntary childlessness. Health care workers need to consider the woman's socioeconomic characteristics, country of birth, and years in Sweden when such information is given.

This study compares prostaglandin E2 (PGE2) gel and oxytocin for the initiation of labor in term pregnancies with a moderately favorable cervix (Bishop score 5-8). Compared with a matched group, 48 cases treated with PGE2 gel (2.5 mg intravaginally) required significantly less or no oxytocin, had shorter first stages of active labor, and had no increased risk of uterine hyperstimulation or cesarean section. Initiation of labor with low dose PGE2 when the cervix is moderately favorable is less labor intensive and meets with more patient satisfaction.