Labor length among overweight and obese women undergoing induction of labor

Abstract

Objective Maternal weight is thought to impact labor. With rising rates of obesity and inductions, we sought to evaluate labor times among induced women by body mass index (BMI) category. Methods Retrospective cohort study of term inductions from 2005 to 2010. BMI categories were: normal weight (NW), overweight (OW), and obese (Ob) (18.5–24.9, 25–29.9, ≥30kg/m2). Kruskal-Wallis tests compared median latent labor (LL) length and active labor (AL) length. Chi-square determined associations. Multivariable logistic regression controlled for confounders. Analyses were stratified by parity. Results A total of 448 inductions were analyzed. For nulliparas, there was no difference in LL by BMI category (p = 0.22). However, OW nulliparas had a longer AL compared to NW and Ob nulliparas (3.2, 1.7, 2.0 h, p = 0.005). For multiparas, NW had the shortest LL (5.5 h, p = 0.025) with no difference in AL among BMI categories (p = 0.42). The overall cesarean rate was 23% with no difference by BMI category (p = 0.95). However, Ob women had a greater percentage of first stage cesareans (41%) and NW had a greater percentage of second stage cesareans (55%), p = 0.06. Conclusion The association between BMI and labor length among inductions differs by phase of labor and parity. BMI also influences the stage of labor in which a cesarean occurs.

Maternal obesity, duration of labor and the role of leptin

“…However, the survival curves that illustrated the duration of active labor were not visually different between normal weight, overweight and obesity classes I and II, in contrast to the survival curves from latent labor when the duration successively increased with BMI class. This finding is in contrast to the previous mentioned study that analyzed latent labor, in which no association was identified with maternal BMI; however, different definitions of the labor phases were employed (71). Our results on latent labor must be considered in light of the factors that may have biased the results.…”

“…It has been demonstrated that the duration of the total time in induced labor increases with a higher maternal weight at the time of delivery (45,59,67,68) and failure to progress is a more common indication for cesarean delivery in obese women with IOL than normal weight women (69,70). Limited studies have assessed the effect of maternal early pregnancy BMI on the duration of induced labor, with contradictory results (58,64,71).…”

“…We identified only one study that compared the latent and active phases of induced labor in relation to maternal early pregnancy BMI (71). The results from study II contribute knowledge regarding the duration of induced labor, both latent and active labor, in nulliparous women with respect to their early pregnancy BMI.…”

Impact Of Physical Activity During Pregnancy On Obstetric Outcomes In Obese Women

“…Students T-Tests were used to compare continuous data between the two independent groups and chi-square tests were used to compare categorical data after testing for normality using Kolmogorov-Smirnov tests. Parity was used as a covariate (nulliparous versus multiparous) in analyzing total time in labor and time in stage 2 of labor as parity has a significant effect on these variables in previous studies 21 , as well as in our dataset (nulliparous women spent significantly more time in stage 2 than multiparous women regardless of physical activity levels, p<0.001). We also stratified our groups by parity in order to better understand the impact of physical activity on time in labor in exclusively nulliparous versus multiparous obese women.…”

Impact of physical activity during pregnancy on obstetric outcomes in obese women

“…Parity was used as a covariate (nulliparous versus multiparous) in analyzing total time in labor and time in stage 2 of labor as parity has a significant effect on these variables in previous studies 21 , as well as in our dataset (nulliparous women spent significantly more time in stage 2 than multiparous women regardless of physical activity levels, p<0.001). We also stratified our groups by parity in order to better understand the impact of physical activity on time in labor in exclusively nulliparous versus multiparous obese women.…”