Impact of Maternal Body Mass Index on Progress and Outcome of Labor in Nulliparous Females

INTRODUCTION

The worldwide prevalence of obesity has increased substantially over the past few decades. Economic, technologic, and lifestyle changes have created an abundance of cheap, high-calorie food coupled with decreased required physical activity. We are eating more and moving less. Obesity is a significant public health concern and is likely to remain so for the foreseeable future ¹.

The most commonly used measurement for defining obesity is BMI, which refers to an individual’s weight in kilograms divided by the square of his or her height in meters. Individuals are deemed overweight when they have a BMI between 25 and 30 kg/m2; obesity is defined as a BMI greater than or equal to 30 kg/m2, and morbid obesity is defined as a BMI greater or equal to 40 kg/m2. It is important to note, however, that BMI can be misleading ².

Both increased and decreased BMI have been demonstrated to be associated with an increased rate of adverse events ³.

Some studies have investigated the impact of maternal BMI on the progress of labor and the length of labor; patients with increased BMI have been

shown to experience slower labor progress, labor dysfunction, and a higher cesarean delivery rate ⁴.

Alterations to the progress of labor in relation to BMI differences could be used to optimize labor management, potentially influencing cesarean delivery rates. However, many of these previous studies have been retrospective with inadequate sample ⁵.

PATIENTS AND METHODS

The study was carried out at the Sayed Galal University Hospital's Obstetrics & Gynecology department. This was prospective cohort study that  had been  include  nulliparous patients attending the labor ward of Al-Hussein and Sayed Galal hospitals, Al-Azhar University, Egypt, during active phase of labor from January 2021 until the end of the specified cases.

Inclusion criteria are:  Nulliparous women, age 20-40 years, BMI more than , less than , or equal to 18.5, full-Term Singleton Pregnancy [ 37-42 weeks gestation calculated by last menstrual period and verified by 1st trimester ultrasonography], cephalic [vertex] presentation and Occipito-Anterior position and in active phase of labour [dilatation of at least 4 cm]

Exclusion criteria are: Multiparous women, age below 20 or over 40, multifetal Pregnancy, major fetal anomalies, malposition, premature Rupture of membranes, maternal pregestational and gestational medical disorders other than obesity and labor  induction      (by           stripping, amniotomy,                prostaglandins or oxytocin infusion)

Methods

The following will be done to the participants:

The pregnant women who took part in the study voluntarily gave their written consent

Name, age, occupation, and location are all taken as part of the whole history

Medical or surgical history (particularly bariatric procedures), any drug sensitivity, or obstetric or operative problem.

Thorough Clinical Examination: General assessment: vital signs (blood pressure and pulse, respiratory rate and temperature), length (in cm) and weight (in kg) metrics (Body mass will be evaluated with a calibrated scale) while topics are wearing the lightest clothing possible and BMI will be determined), head and neck evaluation for jaundice, pallor, pigmentations, edoema, goitre, enlarged lymph nodes, and congested necrosis Inspection: to determine the size of the abdomen, the presence of striae gravidarum, and the presence of pigmentations such as linea nigra. Fundal level, fundal grip to identify the part of the fetus occupying the fundus, umbilical grip to detect the back and foetal limbs, and first pelvic grip to identify the part of the foetus occupying the lower uterine segment and to detect engagement are all examples of obstetric palpation (Maneuvers of Leopold).

Laboratory Investigations: CBC, kidney and liver function, coagulation profile and FBS, PPBS, HBA1C and urine analysis

Ultrasound: Ultrasound examination will be done, to Asses Biophysical Profile (BPP), which includes: Amniotic Fluid Index (AFI), Fetal Movement, Fetal Tone, and Fetal Breathing, number of fetuses (Exclusion of multiple pregnancies), position of the Placenta, biometry, Gestational age, Presentation (at term), estimated Fetal weight using Hadlock formula depending on BPD, AC, FL for assessment of normal growth, macrosomia, and IUGR and umbilical artery Doppler flowmetry for assessment of fetal condition.

Monitoring progress and complications (Primary outcome): Patients had been weighed and had their height measured. This study depends on the pre-labor weight rather than pre- pregnancy weight. Patients had been divided into groups using their BMI based on WHO criteria. Group A had been include women with normal BMI of [18.5- 24.9]. Group B had been include overweight women with BMI of [25- 29.9]. Group C   had been include obese women with BMI of at least 30 which will be subdivided into 3 sub-groups corresponding to the 3 classes of obesity according to who criteria [10], Sub- group C1 with BMI of 30-34.9, Sub-group C2 with BMI of 35-39.9, Sub-group C3 with BMI of at least 40. Group D  had been include underweight women with body mass index less than 18.5. Friedman curve had been used to monitor progress of labor in terms of cervical dilatation and head descent vs. time.

Monitoring for complication: A check-list of peripartum complications had been prepared and fulfilled for each patient of each group

Neonatal assessment (secondary outcome): The neonatal birth weight. Follow up the neonate for Apgar score at 1 & at 5 min by trained pediatrician. Neonatal admission to ICU

Data collection and statistical analysis: Utilizing Microsoft Excel software, data from the history, basic medical examination, laboratory investigations, and outcome measures are coded, input, and analyzed. Statistical Package for the Social Sciences (SPSS version 20.0) (Statistical Package for the Social Sciences) software was used to analyses the data. Per the type of data, qualitative data is represented as a number and a percentage, while quantitative data is represented as a mean and standard deviation. the next tests were used to determine the significance of differences: correlation by Pearson's correlation or Spearman's correlation. For significant results, the P value was set at 0.05, and for very significant outcomes, it was set at <0.001.

RESULTS

In terms of weight and BMI, there is a considerable disparity between the 4 groups. Table (1)

Table 1: Demographic data between the studied groups

There is a substantial variations in birth weight and Apgar at 1 and 5 minutes across the four groups tested. Table (2)

Table 2: Neonatal characteristics of the studied groups

There is a significant difference between the four studied groups regarding active phase duration, cervical dilation rate, second stage duration and labor duration. Table (3)

Table 3: Intrapartum data of the studied groups

There is a significant difference between the four studied groups regarding protracted dilatation and type of delivery. Table (4)

Table 4: Labor and delivery outcome of the studied groups

There is a substantial variations between the four studied groups regarding episiotomy and postpartum hemorrhage. Table (5)

* Percentage calculated among all vaginal deliveries only.

Table 5: Complications distribution of the studied groups

There is no discernible difference between the subgroups tested.. Table (6)

Table 6: Intrapartum data of the studied groups

In terms of problems, there is no substantial difference between the four groups evaluated. Table (7)

* Percentage calculated among all vaginal deliveries only.

Table 7: Complications distribution of the studied groups