From observation to aetiology: a case report of a twin fetus-in-fetu and a revisit of the known rarity.

A baby girl presented with an antenatal diagnosis of a retroperitoneal tumour. Postnatal imaging suggested that this mass contained two fetiform structures with spine and long bone formation. This teratomatous mass was completely excised at 3 weeks of age. Histology was consistent with twin fetuses-in-fetu, revealing two fetiform masses each with an umbilical cord connecting to a common placenta-like mass. Despite a difference in the weight of the twin fetuses-in-fetu, the level of organogenesis was identical and corresponded to fetuses of 10 weeks of gestation. Each mass had four limbs, intact skin, rib cage, intestines, anus, ambiguous genitalia, primitive brain tissue and a spine with ganglion cells in the cord. Although considered a mature teratoma in the current World Health Organization classification, the theory of formation from multiple pregnancies has been commonly implied in more recent literature. The true aetiology of this rare condition remains unclear.

Randomised controlled study to assess skill retention at 6 vs 12 months after simulation training in shoulder dystocia.

Introduction: Current evidence suggests annual training in the management of shoulder dystocia is adequate. The aim of this trial is to test our hypothesis that skills start to decline at 6 months after training and further decline at 12 months. Methods: In this randomised, single-blinded study, 13 obstetricians and 51 midwives were randomly assigned to attend a 1-hour mixed lecture and simulation session on shoulder dystocia management. Training was conducted on group 2 at month '0' and on group 1 at month '6'. Their knowledge scores (primary outcome) were assessed before (pre-training), immediately after the training (at-training) and retested at month '12' (post-training). Results: Two-way repeated-measures analysis of variance showed a statistically significant interaction between the testing time frame (pre-training, at-training and post-training) on the score (p<0.001), but no significant interaction between the groups on the score (p=0.458).Compared to pre-training, the score increased after the simulation training (at-training) in both group 1 (8.69 vs 14.34, p<0.001) and group 2 (9.53 vs 14.66, p< 0.001), but decreased at 6 months post- training in group 1 (14.34 vs 11.71, p<0.001) and at 12 months post-training in group 2 (14.66 vs 11.96, p< 0.001). However the score was better than before the training. There was no significant difference in the post -training score (11.71vs 11.96, p=0.684) between both groups. Conclusions: Our study demonstrated that simulation training results in short-term and long-term improvement in shoulder dystocia management however knowledge degrades over time. Ongoing training is suggested at a minimum of 12 months' interval for all members of the obstetrics team including midwives and doctors.