Virtual poster abstracts Ultrasound (US) fetal biometry and feto-maternal Doppler were performed within 72h from admission. For longitudinal growth assessment we calculated EFW z-velocity between the EFW z-score at recruitment US and neonatal weight z-score. Results: We found no differences in maternal baseline characteristics, except maternal age, significantly higher in PPROM patients than in PTL group (p = 0,012), and smoking habit, significantly higher in PPROM than in the uncomplicated group (p = 0,038). Gestational age at first US was significantly lower in PTL and PPROM groups (p < 0,001). SGA was significantly more frequent in fetuses from PTL and PPROM mothers than in the uncomplicated group (PTL p = 0,009; PPROM p = 0,011). There were no significant differences in the umbilical artery pulsatility index (PI), middle cerebral artery PI, uterine artery PI and cerebro-placental ratio among the groups. As expected, women with PTL or PPROM presented earlier GA at delivery (PTL p < 0,001; PPROM p < 0,001). SGA neonates were significantly more frequent in women with PPROM than in the uncomplicated group (p = 0,02). The analysis did not show statistically significant differences in EFW z-velocity. Conclusions: Our data show a higher proportion of SGA fetuses at admission due to PTL or PPROM and a higher proportion of SGA at delivery in women with PPROM as compared to uncomplicated patients. This is a exploratory study showing very preliminary data from a cohort planned to be finished for recruitment in two years. More research is needed to confirm the results and to clarify the causes. VP38.06 Effect of delivery mode on neonatal outcomes in smallfor-gestational-age fetuses

A case of recurrence of pyoderma gangrenosum after COVID-19 vaccineDear Editor, Pyoderma gangrenosum (PG) is a rare neutrophilic inflammatory skin condition characterized by painful purulent pustules or enlarging ulcers with raised, undermined and violaceous borders. PG has been associated with various systemic diseases, such as inflammatory bowel disease, monoclonal gammopathy, hematologic disease, inflammatory arthritis, malignancy and hidradenitis suppurativa. 1 There have been several reported cases of occurrences and recurrences of PG after COVID-19 infection and vaccination. In this case report, we describe a patient with a history of PG, which had been in remission for several years prior to vaccination that experienced a recurrence of PG at the same sites as the previous involvement.

The aim of this study is to describe the perinatal outcomes associated to FGR in a portuguese tertiary referral unit and to compare two consecutively implemented protocols (before and after February 2019). Methods: Retrospective study of singleton pregnancies diagnosed with FGR who delivered between 2018 and 2019 in Santa Maria Hospital. In our department, before February 2019, the delivery of a growth restricted fetus was programd for 37 weeks and it was anticipated if the pulsatility index of the ductus venosus (DV) was >95th centile from 28 weeks or if the umbilical artery end diastolic flow (UAEDF) was inverted from 32 or absent from 34 weeks. After February 2019, the delivery is anticipated if the A wave of the DV is absent or inverted from 26 weeks or if the UAEDF is reversed from 32 or absent from 34 weeks. We evaluated and compared obstetric and neonatal outcomes.