Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Subscribe Contacts Login 


 
 Table of Contents  
ORIGINAL ARTICLE
Year : 2015  |  Volume : 28  |  Issue : 4  |  Page : 858-863

Effect of obesity on the length of the first and second stages of labor


1 Department of Obstetrics and Gynecology, Faculty of Medicine, Menoufia University, Menoufia, Egypt
2 Nabarouh Central Hospital, Dakahlia, Egypt

Date of Submission02-Dec-2014
Date of Acceptance08-Feb-2015
Date of Web Publication12-Jan-2016

Correspondence Address:
Shrouk A Mohamed Abdou
El-Semad City, Talkha, Dakahlia, 35717
Egypt
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1110-2098.173604

Rights and Permissions
  Abstract 

Objective
This study was designed to evaluate the length of the first and second stages of labor in nulliparous obese Egyptian women and compare them with those in women with normal BMI.
Background
Maternal obesity is now the most common risk factor for maternal mortality in developed countries and is also associated with a wide spectrum of adverse pregnancy outcomes. The duration of first stage of labor, the rate of cesarean delivery, and inadequate progress of cervical dilatation during labor were found to be higher in women with BMI more than 30 compared with women of average weight.
Participants and methods
Nulliparous women of more than 37 gestational weeks who were in labor were included in this study. First-visit BMI was used to categorize weight as normal (≤24) or obese (≥30). Over 12 months (study period), we observed 603 deliveries; 239 were nulliparous and 211 were term singleton. Eighty women met the inclusion criteria: 40 women with normal BMI constituting the control group and 40 obese women who constituted the study group.
Results
The duration of first stage of labor was significantly longer in obese women compared with normal weight women (19.76 ± 0.77 vs. 16.87 ± 0.66 h; P < 0.001), whereas the duration of the second stage of labor showed no significant difference between obese and normal weight women (61.0 ± 34.8 vs. 60.9 ± 34.3 min; P = 0.990). When adjusted for age, hypertension, and induction, the likelihood of completing stages I and II was significantly lower among obese nulliparous than among those with BMI 24 or less.
Conclusion
About half of nulliparous women in our population are obese and the duration of stage I is significantly longer among them, whereas the second stage of labor may be independent of maternal BMI. The second stage in the nulliparous parturient woman does not appear to be longer or more likely to end in cesarean delivery on the basis of prepregnancy BMI

Keywords: BMI, first stage, labor, obesity, second stage


How to cite this article:
Samy M, Sanad ZF, Emara MA, Mohamed Abdou SA. Effect of obesity on the length of the first and second stages of labor. Menoufia Med J 2015;28:858-63

How to cite this URL:
Samy M, Sanad ZF, Emara MA, Mohamed Abdou SA. Effect of obesity on the length of the first and second stages of labor. Menoufia Med J [serial online] 2015 [cited 2024 Mar 29];28:858-63. Available from: http://www.mmj.eg.net/text.asp?2015/28/4/858/173604


  Introduction Top


The prevalence of obesity is increasing worldwide and this trend also affects women of reproductive age. Maternal obesity is now the most common risk factor for maternal mortality in developed countries and is also associated with a wide spectrum of adverse pregnancy outcomes [1] .

In the longer term, obesity and excessive weight gain during pregnancy are associated with increased risks for cardiovascular and metabolic diseases for the mother and with increased risks for obesity in the offspring [2],[3] .

Gestational diabetes, hypertension, preeclampsia, macrosomia, induction of labor, cesarean delivery, postpartum hemorrhage, post-term pregnancy, preterm pregnancy, genital infection, urinary infection, wound infection, intrauterine fetal death, neonatal death, long hospitalization, birth defects, low Apgar score, neural tube defects, thromboembolic events, neonatal icterus, anemia, varicosity, and shoulder dystocia are some of the complications indicated [4],[5] .

Some studies reported an increase in some of the above, which may indicate the consequence of obesity and high maternal weight [6] .

The impact of high maternal weight on labor is the subject of several studies, with varying results. One study reported no important difference in basal uterine contractility between overweight women and those of normal weight, but in women with BMI more than 25 the need for oxytocin during labor, as well as the duration of labor, including the active phase of labor, was higher than in patients of normal weight [7] .

Another study on the rate of cesarean delivery due to prolongation of first stage of labor found the incidence of cesarean delivery to be higher in overweight and obese women even if the neonatal weights were the same. The study also found that uterine contractility and frequency of contractions and increased ionized calcium (Ca +2 ) flux during labor in obese women were less than in normal weight women [8] .

The duration of first stage of labor, the rate of cesarean delivery, and inadequate progress of cervical dilatation during labor were found to be higher in women with BMI more than 30 compared with women of average weight. In contrast, another study revealed that there was no difference in the duration of labor or delivery method in normal and obese women [9] .

Studies on the characteristics of labor in obese gravid women have been limited. We are aware of only two studies that examined the duration of second stage in a nulliparous population categorized by BMI. Obesity was associated with a shorter second stage, compared with normal weight, in one study, whereas the other study demonstrated no difference in the duration of second stage between obese and normal weight participants [10],[11] .

This study was designed to evaluate the length of the first and second stages of labor in nulliparous obese Egyptian women and compare them with women of normal BMI.


  Participants and methods Top


This study included 40 nulliparous women aged 20-36 years at more than 37 gestational weeks who were in labor, along with 40 normal women who served as controls. They were selected from Bab El Shearia Hospital, Al-Azhar University, during the period from May 2012 to May 2013.

The inclusion criteria:

  1. The women had to be either obese (BMI≥30), to constitute the study group, or of normal weight (BMI≤24), to constitute the control group;
  2. They had to be nulliparous, with a singleton pregnancy of a reliable gestational age of at least 37 weeks, and in spontaneous labor.


The women were subjected to at least four digital examinations to allow us to better describe labor progression with sufficient data.

The exclusion criteria:

  1. BMI ranging between 25 and 29.9, or less than 18.5 (women with BMI between 18.5 and 24.9 were considered as the control group);
  2. Multiple gestations;
  3. Contraindications to vaginal delivery;
  4. Women enrolled initially but who delivered subsequently by cesarean section;
  5. Incidence of placental abruption;
  6. Presence of maternal heart disease; and
  7. Major fetal malformation.


All participants gave written consent after detailed explanation of the purpose of the study through a well-designed structured questionnaire; full data were collected from eligible patients, including detailed personal, menstrual, and obstetric history. BMI was calculated by dividing body weight in kg by height in m 2 . Approval was obtained from the ethical committee for performing the study.

Women were classified into two groups:

  1. Group I (control group): This group comprised 40 women with BMI ranging between 18.5 and 24.9.
  2. Group II (case group): This comprised 40 women with BMI equal to or more than 30.


The primary endpoints of the study were the following:

  1. The length of stage I labor, defined as the time from onset of active phase of labor until full cervical dilatation. After admission, women were monitored from the start of uterine contractions. The optimum rate of uterine contractions considered was 3-4/10 min. Amniotomy was performed when the cervix reached 4 cm dilatation. When augmentation was needed, no prostaglandins were used. Oxytocin was given by intravenous drip infusion at 2.5 mU/min (prepared by adding 1 U/l, infused at the rate of 40 drops/min).
  2. Length of the second stage of labor, defined from full cervical dilatation until expulsion of the fetus. Full cervical dilatation was confirmed by local vaginal examination and when the subjects started to bear down involuntarily.


Secondary outcome parameters included the occurrence of chorioamnionitis, third-degree or fourth-degree perineal tears, postpartum hemorrhage, or neonatal morbidity and mortality.

Statistical analysis

Data were collected and tabulated according to standard statistical methods. Demographic data and primary and secondary outcomes of both groups were compared using the t-test (for quantitative measures), the log-rank test, the c2 -test, and Fischer's exact tests (for categorical measures). A P value less than 0.05 was considered statistically significant.


  Results Top


Over the 12-month (from May 2012 to May 2013) study period, there were 603 deliveries in Bab El Shearia Hospital, Al-Azhar University; of these, 60% (n = 364) were in parous women and 40% (n = 239) in nulliparous women. The rate of delivery before 37 weeks among nulliparous women was 12% (n = 28). Among the 211 term nulliparous pregnancies, 62% (n = 131) were excluded for reasons such as elective cesarean delivery before onset of labor, insufficient cervical exams, late prenatal care, or cesarean section after attempting vaginal delivery.

[Table 1] shows comparison between the two groups as regards age (years); the age of the women in the study group ranged from 20 to 36 years, with a mean of 28 ± 8 years, with statistically nonsignificant difference from the control group (P = 0.934).
Table 1 Comparison between case and control groups as regards age (years)


Click here to view


[Table 2] and [Table 3] show that the two groups differed significantly with respect to hypertension, diabetes, asthma, and augmentation induction rate (P = 0.003, 0.023, 0.157, and 0.141, respectively).
Table 2 Comparison between case and control groups as regards hypertension, diabetes, and asthma


Click here to view
Table 3 Population characteristics as regards spontaneous and augmentation/induction


Click here to view


[Table 4] shows that there was no significant difference between the two groups as regards gestational age at delivery (weeks) and excessive gestational weight gain (P = 0.684, 0.057).
Table 4 Gestational age at delivery (weeks) and excessive gestational weight gain


Click here to view


[Table 5] shows the duration of different stages of labor in the two groups. Obese women spent a median of about 17 h in the first stage of labor versus about 20 h for normal weight women ([Figure 1]). The measurement of the second stage of labor and the total duration of labor were not significantly different between the two groups ([Figure 2]). The mean duration of the third stage of labor was not significantly different between the two groups on the basis of parity, interval from previous pregnancy, maternal weight gain, and rupture of the membrane at the time of admission, but it was longer in the study group in which oxytocin had been used.
Figure 1 Comparison between the two groups as regards stage I labor.



Click here to view
Figure 2 Comparison between the two groups as regards stage II labor.



Click here to view
Table 5 The duration of different stages of labor in the two groups


Click here to view


[Table 6] shows that there were no significant differences between the two groups as regards birth weight (g) (<2500, P = 0.571; 34000, P = 0.074).
Table 6 Characteristics of the two groups as regards birth weight (g)


Click here to view


Duration of stage I labor was compared among women with various complications, including those with augmented or induced labor. Induction and hypertensive disease were associated with significantly longer stage I but not maternal age, diabetes, asthma, and birth weight ([Table 7]).
Table 7 Length of stage I for each characteristic group


Click here to view


[Table 8] displays the median duration of the second stage, expressed in hours and classified by BMI (P = 0.99).
Table 8 Duration (h) of second stage of labor


Click here to view


Induction of labor is a commonly recognized risk factor for cesarean delivery and prolonged labor. Because of a higher frequency of labor induction within this cohort of obese women compared with their normal weight counterparts, the data were analyzed to determine whether the relationship between BMI and duration of second stage of labor differed between those with induced and those with spontaneous labor. The relationship between BMI and second-stage duration did not differ between women with induced and those with spontaneous labor.


  Discussion Top


Obese women have multiple complications during the peripartum period, including a higher rate of cesarean delivery. If the BMI is 30 or more, the rate of cesarean delivery is higher [12] .

Others have noted that even if comorbidities such as hypertension and diabetes are excluded, obese women are more likely to have abdominal delivery [13] , although several studies have noted a higher likelihood of failure to progress necessitating cesarean delivery [14],[15] .

There are many findings in this prospective study. First, in our population at the start of pregnancy one of three was obese. Compared with other studies, the likelihood of obesity appears to be higher in our population, our statistics corresponding to those of Vahratian et al. [10] .

As most women do not lose the weight gained during pregnancy, it is expected that most of the nulliparous women in our population will have a BMI greater than 25 in subsequent pregnancies, which will increase the likelihood of complications [16] .

The second finding was that, as the BMI increases, so does the likelihood of diabetes, hypertension, induction, cesarean delivery, and macrosomia. These complications are consistent with earlier publications and ACOG committee opinion.

For example, some studies reported that, compared with women of normal weight, obese nulliparous women are significantly more likely to have comorbidity (diabetes, hypertension), cesarean delivery, and newborns with weight over 4000 g [10],[17] .

The third finding is that BMI influences stage I of labor but not stage II. The duration of stage I differs significantly among obese and normal weight women. Even when adjusted for confounding variables, obese women are 27% less likely to reach the second stage of labor than women with a normal BMI.

The fourth finding is that there was no association between maternal BMI and length of the second stage in nulliparous women. In addition, maternal BMI in nulliparous women reaching the second stage is not associated with a higher incidence of cesarean delivery.

A retrospective case-control study including 51 obese nulliparous women (BMI>35) and 60 nulliparous normal weight controls (BMI < 26) in spontaneous labor found no difference in the duration of second stage of labor [11] .

Another prospective cohort study that included 71 women during the second stage of labor determined that second-stage duration between obese women and nonobese controls was similar. They also found no increase in the frequency of operative delivery or perineal lacerations [7] .

To the contrary, the Vahratian et al.'s [10] study, which included 612 participants, found that obese nulliparous women had a shorter second stage of labor compared with normal weight controls, contradicting the theoretical notion that soft tissue dystocia may lead to longer labors in obese women.

Our study supports the findings of Verdiales et al. [11] , and Buhimschi et al. [7] , in that we found no evidence of increased second-stage duration in women with increasing BMI, nor did we find an association between BMI and cesarean delivery in women reaching the second stage.

Our results mirror those of Robinson et al. [18] in that increasing BMI appears to be a risk factor for cesarean delivery in the first stage but not in the second stage of labor.

Finally, we grouped women with induced, augmented, and spontaneous labor together. Even though labor was significantly longer for women who were augmented or induced, we were able to control for this variable, and obesity was still a significant risk factor for not completing the first stage of labor [19] .


  Conclusion Top


In conclusion, over one-third of nulliparous women in our population are obese, and the duration of stage I is significantly longer among them. Prospective studies are needed to determine the optimum time intervals for cervical dilation in active phase of labor in obese women.

These data suggest that the characteristics of the second stage of labor may be independent of maternal BMI. The second stage in the nulliparous parturient woman does not appear to be longer or more likely to end in cesarean delivery on the basis of prepregnancy BMI. This knowledge may aid obstetric providers in counseling women about the expected effect of their BMI on their intrapartum course, as well as assist in clinical decision making in women who reach the second stage of labor.

Studies should be conducted to detect the relationship between obesity and cervical effacement, fetal assessment, fetal outcome, and mode of delivery.


  Acknowledgements Top


Conflicts of interest

There are no conflicts of interest.

 
  References Top

1.
Confidential Enquiry into Maternal and Child Health (CEMACH). Why mothers die. The sixth report into maternal deaths in the United Kingdom. London: RCOG Press; 2004.  Back to cited text no. 1
    
2.
Callaway LK, Prins JB, Chang AM, McIntyre HD. The prevalence and impact of overweight and obesity in an Australian obstetric population. Med J Aust 2006; 184 :56-59.  Back to cited text no. 2
    
3.
Lawlor DA, Smith GD, O′Callaghan M, Alati R, Mamun AA, Williams GM, Najman JM. Epidemiologic evidence for the fetal overnutrition hypothesis: findings from the mater-university study of pregnancy and its outcomes. Am J Epidemiol 2007; 165 :418-424.  Back to cited text no. 3
    
4.
Hamon C, Fanello S, Catala L, Parot E. Maternal obesity: effects on labor and delivery: excluding other diseases that might modify obstetrical management. J Gynecol Obstet Biol Reprod (Paris) 2005; 34 :109-114.  Back to cited text no. 4
    
5.
Seligman LC, Duncan BB, Branchtein L, Gaio DS, Mengue SS, Schmidt MI. Obesity and gestational weight gain: cesarean delivery and labor complications. Rev Saude Publica 2006; 40 :457-465.  Back to cited text no. 5
    
6.
Kristensen J, Vestergaard M, Wisborg K, Kesmodel U, Secher NJ. Pre-pregnancy weight and the risk of stillbirth and neonatal death. BJOG 2005; 112 :403-408.  Back to cited text no. 6
    
7.
Buhimschi CS, Buhimschi IA, Malinow AM, Weiner CP. Intrauterine pressure during the second stage of labor in obese women. Obstet Gynecol 2004; 103 :225-230.  Back to cited text no. 7
    
8.
Zhang J, Bricker L, Wray S, Quenby S. Poor uterine contractility in obese women. BJOG 2007; 114 :343-348.  Back to cited text no. 8
    
9.
Galtier-Dereure F, Boegner C, Bringer J. Obesity and pregnancy: complications and cost. Am J Clin Nutr 2000; 71(Suppl): 1242S-1248SS.  Back to cited text no. 9
    
10.
Vahratian A, Zhang J, Troendle JF, Savitz DA, Siega-Riz AM. Maternal prepregnancy overweight and obesity and the pattern of labor progression in term nulliparous women. Obstet Gynecol 2004; 104 (Pt 1): 943-951.  Back to cited text no. 10
    
11.
Verdiales M, Pacheco C, Cohen WR. The effect of maternal obesity on the course of labor. J Perinat Med 2009; 37 :651-655.  Back to cited text no. 11
    
12.
American College of Obstetricians and Gynecologists (ACOG). ACOG committee opinion. Number 319, October 2005. The role of obstetrician-gynecologist in the assessment and management of obesity. Obstet Gynecol 2005; 106 :895-899.  Back to cited text no. 12
    
13.
Baeten JM, Bukusi EA, Lambe M. Pregnancy complications and outcomes among overweight and obese nulliparous women. Am J Public Health 2001; 91 :436-440.  Back to cited text no. 13
    
14.
Young TK, Woodmansee B. Factors that are associated with cesarean delivery in a large private practice: the importance of prepregnancy body mass index and weight gain. Am J Obstet Gynecol 2002; 187 :312-318; discussion 318-320.  Back to cited text no. 14
    
15.
Sheiner E, Levy A, Menes TS, Silverberg D, Katz M, Mazor M. Maternal obesity as an independent risk factor for caesarean delivery. Paediatr Perinat Epidemiol 2004; 18 :196-201.  Back to cited text no. 15
    
16.
Rooney BL, Schauberger CW. Excess pregnancy weight gain and long-term obesity: one decade later. Obstet Gynecol 2002; 100 :245-252.  Back to cited text no. 16
    
17.
Weiss JL, Malone FD, Emig D. Faster Research Consortium. Obesity, obstetric complications and cesarean delivery rate a population-based screening study. Am J Obstet Gynecol 2004; 190 :1091-1097.  Back to cited text no. 17
    
18.
Robinson BK, Mapp DC, Bloom SL, Rouse DJ, Spong CY, Varner MW, et al. Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) of the Maternal-Fetal Medicine Units Network (MFMU). Increasing maternal body mass index and characteristics of the second stage of labor. Obstet Gynecol 2011; 118 :1309-1313.  Back to cited text no. 18
    
19.
Hilliard AM, Chauhan SP, Zhao Y, Rankins NC. Effect of obesity on length of labor in nulliparous women. Am J Perinatol 2012; 29 :127-132.  Back to cited text no. 19
    


    Figures

  [Figure 1], [Figure 2]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8]


This article has been cited by
1 THE EFFECTS OF OBESITY ON THE ACTIVE PHASE OF THE FIRST STAGE OF LABOR
Dekan Mahmood, Rozhan Khalil
JOURNAL OF SULAIMANI MEDICAL COLLEGE. 2022; 12(4): 417
[Pubmed] | [DOI]
2 Effect of obesity on labor duration among nulliparous women with epidural analgesia
Rita Polónia Valente,Patrícia Santos,Tiago Ferraz,Nuno Montenegro,Teresa Rodrigues
The Journal of Maternal-Fetal & Neonatal Medicine. 2019; : 1
[Pubmed] | [DOI]
3 Effects of gestational weight gain and body mass index on obstetric outcome
Kiymet Yesilçiçek Çalik,Nazende Korkmaz Yildiz,Reyhan Erkaya
Saudi Journal of Biological Sciences. 2018;
[Pubmed] | [DOI]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Introduction
Participants and...
Results
Discussion
Conclusion
Acknowledgements
References
Article Figures
Article Tables

 Article Access Statistics
    Viewed3331    
    Printed127    
    Emailed0    
    PDF Downloaded229    
    Comments [Add]    
    Cited by others 3    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]