Symphysis-fundal height correlates with adverse delivery and neonatal outcomes in induced full-term and premature pregnancies

Background: Assessing outcomes of birth in induced patients (full-term and premature) in relation with symphysis-fundal height (SFH) measurement. Methods: A prospective enrollment of induced patients was performed at the Obstetrics and Gynecology Unit of Arcispedale Sant'Anna of Ferrara. Reasons for induction, Bishop's score, body mass index, gestational age, parity, mode of induction, number of induction cycles, time of active labor phase, Cesarean section, operative vaginal birth, post-partum hemorrhage, arterial cord pH, neonatal intensive care admission, size at birth were recorded. Correspondence analysis was applied to analyze independent relationships. These relationships were converted into probabilities. Probabilities for outcomes variables were plotted along with values of SFH and trends were tested. Results: Significant trends of increasing probability of adverse birth and labor outcomes were observed for SFH from 34 cm or less to over 37 cm: two cycles of induction (best fit p = 0.002); three cycles of induction (best fit p = 0.002); Cesarean section (best fit p = 0.027); higher length of active phase of labor (best fit p = 0.002); operative vaginal birth (best fit p = 0.002); arterial blood pH below or equal to 7.15 (best fit p = 0.006); post-partum minor hemorrhage (best fit p = 0.002), post-partum major hemorrhage (best fit p = 0.006). Conclusion: In induced pregnancies, SFH over 34 cm increased the probability of both neonatal and labor adverse outcomes, independently of gestational age.