I DUE REGIMI POSOLOGICI DEL MISOPROSTOLO ORALE NELL'INDUZIONE AL TRAVAGLIO DI PARTO: STUDIO RETROSPETTIVO NELL' UNITÀ OPERATIVA DI GINECOLOGIA ED OSTETRICIA "G.SALESI" DI ANCONA

Introduction. The induction of labour in childbirth is a medical intervention that is progressively increasing over the years, making continuous research and constant updates on the various induction methods essential. In January 2021, the sale of 25 mcg tablets of misoprostol was approved in Italy; it can be administered through two dosage regimens: 25 micrograms orally every two hours or 50 micrograms orally every four hours. This new low-dose formulation of oral misoprostol has benefits, however, like the other induction methods its use may result in some adverse reactions. Objectives. The objective of this thesis is to investigate and detect the presence of statistically significant differences in maternal and fetal outcomes when the two dosage regimens of oral misoprostol are adopted. The sample was divided into groups based on certain predictive indices of induction success or failure. The justification for this division is attributed to the assumption that the two misoprostol dosage regimens may lead to different outcomes depending on the group examined. Materials and methods. The study conducted is a retrospective cohort, data collection took place at the Department of Obstetrics and Gynaecology of the Azienda 'G. Salesi' and was conducted from 15/08/2023 to 28/09/2023. The database consisted of 157 women and included all patients who underwent induction of labour by means of low-dose oral misoprostol. The sample was divided into: women aged > 35 years, women aged < 35 years, nulliparous, multiparous, women with Bishop index < 4, women with BMI < 30 kg/m2. Data were collected in an Excel database and analysed using R software version 4.2.2. Results. Only differences found to be statistically significant were considered within the study. The average duration of induction of labour was reduced in multiparous women using the first dosage regimen of oral misoprostol. With regard to the type of delivery, in women aged > 35 years, nulliparous women and women with Bishop index > 4, higher rates of vaginal deliveries and caesarean sections were found when oral misoprostol was administered according to the first dosage regimen and higher rates of operative deliveries when the second dosage regimen was used. In women aged < 35 years, on the other hand, only the percentage of operative deliveries was significant when the second dosage regimen was used. With regard to indications for caesarean section due to cardiotocogram atypia, in women > 35 years of age, the second dosage regimen showed a significant percentage increase, whereas in women with BMI < 30 kg/m2, a higher percentage of indications for caesarean section due to cardiotocogram atypia was obtained when the first dosage regimen was used. Regarding the use of oxytocin for continuing induction, women aged < 35 years, with BMI < 30 kg/m2 and women with Bishop index < 4 received oxytocin in higher percentages when the first dosage regimen of misoprostol was used. Regarding spontaneous perineal tears, in the group of multiparous women and in the group of women with BMI < 30 kg/m2, higher percentages of grade 1 and grade 2 tears were associated with the first regimen, grade 3 tears were associated with the second dosage regimen. For neonatal outcomes, this study showed that the Apgar score values at the first and fifth minutes were comparable in the two regimens, with an average score of 9 at the first minute and 10 at the fifth minute. Conclusions. The results show how similar regimens led to different results depending on the group examined. This observation highlights the idea that there are other factors influencing the results studied than the exact misoprostol regimen used. For the future, it seems necessary to direct research towards clinical studies focusing on specific populations in order to evaluate the possibility of tailor-made induction regimens, thus achieving greater customisation of labour induction.