Induction of labor in women with a scarred uterus: does grand multiparity affect the risk of uterine rupture?

Perinatal outcomes in grand multiparous women stratified by parity- A large multicenter study

OBJECTIVE

To assess the effect of each additional delivery among grand multiparous (GMP) women on maternal and neonatal outcomes.

METHODS

A multi-center retrospective cohort study that examined maternal and neonatal outcomes of GMP women (parity 5-10, analyzed separately for each parity level) compared to a reference group of multiparous women (parity 2-4). The study population included grand multiparous women with singleton gestation who delivered in one of four university-affiliated obstetrical centers in a single geographic area, between 2003 and 2021. We excluded nulliparous, those with parity > 10 (due to small sample sizes), women with previous cesarean deliveries (CDs), multifetal gestations, and out-of-hospital deliveries. The primary outcome of this study was postpartum hemorrhage (PPH, estimated blood loss exceeding 1000 ml, and/or requiring blood product transfusion, and/or a hemoglobin drop > 3 g/Dl). Secondary outcomes included unplanned cesarean deliveries, preterm delivery, along with other adverse maternal and neonatal outcomes. Univariate analysis was followed by multivariable logistic regression.

RESULTS

During the study period, 251,786 deliveries of 120,793 patients met the inclusion and exclusion criteria. Of those, 173,113 (69%) were of parity 2-4 (reference group), 27,894 (11%) were of parity five, 19,146 (8%) were of parity six, 13,115 (5%) were of parity seven, 8903 (4%) were of parity eight, 5802 (2%) were of parity nine and 3813 (2%) were of parity ten. GMP women exhibited significantly higher rates of PPH starting from parity eight. The adjusted odds ratios (aOR) were 1.19 (95 % CI: 1.06-1.34) for parity 8, 1.17 (95 % CI: 1.01-1.36) for parity 9, and 1.39 (95 % CI: 1.18-1.65) for parity 10. Additionally, they showed elevated rates of several maternal and neonatal outcomes, including placental abruption, large-for-gestational age (LGA) neonates, neonatal hypoglycemia, and neonatal seizures. Conversely, they exhibited decreased risk for other adverse maternal outcomes, including preterm deliveries, unplanned cesarean deliveries (CDs), vacuum-assisted delivery, and third- or fourth-degree perineal tears and small-for-gestational age (SGA) neonates. The associations with neonatal hypoglycemia, and neonatal seizure were correlated with the number of deliveries in a dose-dependent manner, demonstrating that each additional delivery was associated with an additional, significant impact on obstetrical complications.

CONCLUSION

Our study demonstrates that parity 8-10 is associated with a significantly increased risk of PPH. Parity level > 5 correlated with increased odds of placental abruption, LGA neonates, neonatal hypoglycemia, and neonatal seizures. However, GMP women also demonstrated a reduced likelihood of certain adverse maternal outcomes, including unplanned cesarean, preterm deliveries, vacuum-assisted deliveries, SGA neonates, and severe perineal tears. These findings highlight the importance of tailored obstetrical care for GMP women to mitigate the elevated risks associated with higher parity.

Partogram of Grandmultiparous Parturients: A Multicenter Cohort Study

Sparse and conflicting data exist regarding the normal partogram of grand-multiparous (GMP, defined as parity of 6+) parturients. Customized partograms may potentially lower cesarean delivery rates for protraction disorders in this population. In this study, we aim to construct a normal labor curve of GMP women and compare it to the multiparous (MP, defined as parity of 2-5) partogram. We conducted a multicenter retrospective cohort analysis of deliveries between the years 2003 and 2019. Eligible parturients were the trials of labor of singletons ≥37 + 0 weeks in cephalic presentation with ≥2 documented cervical examinations during labor. Exclusion criteria were elective cesarean delivery without a trial of labor, preterm labor, major fetal anomalies, and fetal demise. GMP comprised the study group while the MP counterparts were the control group. A total of 78,292 deliveries met the inclusion criteria, comprising 10,532 GMP and 67,760 MP parturients. Our data revealed that during the first stage of labor, cervical dilation progressed at similar rates in MPs and GMPs, while head descent was a few minutes faster in GMPs compared to MPs, regardless of epidural anesthesia. The second stage of labor was faster in GMPs compared to MPs; the 95th percentile of the second stage duration of GMPs (48 min duration) was 43 min less than that of MPs (91 min duration). These findings remained similar among deliveries with and without epidural analgesia or labor induction. We conclude that GMPs' and MPs' cervical dilation progression in the active phase of labor was similar, and the second stage of labor was shorter in GMPs, regardless of epidural use. Thus, GMPs' uterus function during labor corresponds, and possibly surpasses, that of MPs. These findings indicate that health providers can use the standard partogram of the active phase of labor when caring for GMP parturients.