Postpartum hemorrhage (PPH), defined as blood loss more than 500 ml in normal vaginal delivery and > 1000 ml blood loss in cesarean delivery. PPH is a leading cause of maternal morbidity and mortality worldwide.It is a significant obstetric complication that requires prompt recognition and management to prevent adverse outcomes.  The mode of labor onset, specifically induction of labor versus spontaneous labor, has been a subject of interest and debate regarding its association with PPH¹. Excessive blood loss during childbirth can lead to maternal morbidity², including the need for blood transfusions and anemia, making it important to understand the differences in blood loss between induced and spontaneous labor. Induction of labor may increase the risk of postpartum hemorrhage (PPH) due to factors like uterine atony and coagulation abnormalities. These complications are more common in women with underlying maternal conditions or obstetric indications, which can impair hemostasis and contribute to excessive bleeding³. Induction of labor is a common and evolving practice used to manage various pregnancy complications, including post-term pregnancy and fetal distress. Two primary methods of induction—mechanical (e.g., Foley catheter, osmotic dilators) and pharmacological (e.g., prostaglandins, oxytocin)—are employed to ripen the cervix and stimulate contractions, particularly when the Bishop score is unfavorable. While effective, caution is necessary with prostaglandins, especially in women with a history of cesarean sections, due to the risk of uterine rupture⁴. The indication of induction has changed from fetal death to elective induction to meet the convenience of physician and parturient. The incidence of induction varies from setting to setting ranging from 5% to 22% of all labour room admissions and depends upon the institutional protocol. In spite of many issues like proper indication, maternal and fetal hazards and increased incidence of cesarean section, the rate of induction is on rise^5-7. Labor induction is indicated in conditions such as hypertensive disorders, eclampsia, post-term pregnancy, IUFD, congenital abnormalities, PROM, Rh isoimmunization, gestational diabetes, IUGR, and placental abruption, with the goal of optimizing outcomes for both mother and newborn⁸. Induction of labor, while offering clinical benefits, raises concerns about increased blood loss and the risk of postpartum hemorrhage (PPH), particularly due to factors like uterine atony and oxytocin-induced uterine hyperstimulation. Genital tract trauma, influenced by less favorable cervical conditions in induced labor, can also contribute to PPH. Although studies on the association between induction and PPH have produced conflicting results, further research is needed to clarify the relationship. This study aims to quantify blood loss in both induced and spontaneous labor using the gravimetric method to provide a more accurate assessment of PPH risks^9,10.

AIM

The aim of this study is to determine if induction of labor leads to increased blood loss or postpartum hemorrhage (PPH) compared to spontaneous onset of labor. Additionally, the study aims to quantify the difference in blood loss between induction and spontaneous labor patients.

This study was conducted in the labor room of the Department of Obstetrics and Gynaecology at Sardar Patel Medical College and A.G. Hospital, Bikaner, from February 2023 to May 2024. It was a hospital-based, prospective observational study designed to investigate whether induction of labor leads to increased blood loss or a higher incidence of postpartum hemorrhage (PPH) compared to spontaneous onset of labor. The study employed the gravimetric method to accurately measure blood loss in both groups of patients, providing a more reliable assessment of PPH risks in induced and spontaneous labor.The study utilized consecutive sampling as its sampling technique. Patients who met the inclusion criteria were those who provided written consent, had a singleton gestation, were in vertex position, and had live births. The exclusion criteria encompassed several conditions and factors, including breech delivery, gestational diabetes mellitus, placenta previa, placental abruption, chorioamnionitis, multiple pregnancies, known coagulation disorders, patients on anticoagulant or antiplatelet drugs, hypertensive conditions (such as preeclampsia, eclampsia, and HELLP syndrome), previous cesarean delivery or uterine scars, intrauterine death, and polyhydramnios. These exclusions ensured a more homogenous study population and minimized confounding variables that could affect the outcomes of blood loss and postpartum hemorrhage.

SAMPLE SIZE

The study was included a sample size of 200 patients who meet the inclusion criteria. 100 spontaneous progression of labor patients and 100 induced patients. A sample size of 120 patients was required at 80% study power and alpha error 5%. Prevalence of failure of induction by prostaglandins is not more than 20% as per reference article. 

After adding 10% attrition the sample size was 200.

Prevalance=20% 

Q=1-p

Power of study -80% so z =1.96

d= error that is 10%

N =Z2 pq/d2

TABLE 1: Distribution of cases according to their Age

Maximum 60% of cases had age between 19 – 25 yrs in group A followed by 35% were in 26 – 30 yrs whereas minimum 1% had >35 yrs age. Maximum 63% of cases had age between 19 – 25 yrs in group A followed by 28% were in 26 – 30 yrs whereas minimum 4% had >35 yrs age. Mean age was 24.71 ± 3.84 yr in group A whereas 25.15 ± 4.23 yr in group B.

TABLE 2 : Distribution of cases according to their Parity

In group A, maximum 49% of cases were multigravida followed by 40% were primi gravida whereas minimum 11% were grand multipara. In group B, maximum 47% of cases were primigravida followed by 43% were multigravida whereas minimum 10% were grand multipara. 

TABLE 3: Distribution of cases according to their Period of gestation

In group A, maximum 64% of cases were in 37 – 40 wks of gestation followed by 33% were <37 wks whereas minimum 3% were >40 wks. In group B, maximum 77% of cases were in 37 – 40 wks of gestation followed by 18% were <37 wks whereas minimum 5% were >40 wks. Induction before 37weeks was mainly done in cases with leaking PV or

PPROM. 

Graph 1: Distribution of cases according to their pre delivery and post delivery blood pressure

In group A, mean SBP was 117.18 ± 7.61 mm of Hg whereas 118.20 ± 8.47 mm of Hg in group B.In group B, mean DBP was 76.74 ± 5.55 mm of Hg whereas 77.46 ± 5.33 mm of Hg in group B. In group A, post delivery mean SBP was 116.92 ± 7.48 mm of Hg whereas 120.04 ± 9.07 mm of Hg in group B. (p<0.05).In group B, post delivery mean DBP was 77.06 ± 5.66 mm of Hg whereas 78.2 ± 5.00 mm of Hg in group B. (p<0.01)

TABLE 4: Distribution of cases according to indication of induction of labour

In group A no indication of induction was seen whereas in group B, 56% of cases were induced due to elective or patient request followed by 18% were had PROM / Leaking PV and 21% had due dated pregnancy. (p<0.05)

TABLE 5: Distribution of cases according to indication of induction methods

In group A no induction was seen whereas in group B, 77% of cases were induced by inj. Oxytocin followed by 21% were by mixed method either dianoprost gel + oxytocin or misoprostol + oxytocin and only 2% used dianoprost gel. (p<0.05).

TABLE 6: Distribution of cases according to Hb levels post delivery

Maximum 44% controls and 48% cases had 9 – 10.9 gm/dl post delivery Hb.  In group A, post delivery mean Hb was 9.91 ± 1.66 mg/dl whereas 10.48 ± 1.56 mm of Hg in group B. (p<0.01)

TABLE 7: Blood loss post delivery with duration of labor

Above table shows mean blood loss was lower in cases 299.09 ± 161.39 ml in comparison to controls 310.83 ± 241.6 ml when duration of labour was <6hr.  In duration of labour 6-10 hr the mean blood loss was higher in cases 341.0 ± 159.68 whereas 266.92 ± 243.56 in controls and the difference was statistically significant. (p<0.05) Mean blood loss in cases was 313.33 ± 162.60 ml whereas 286.0 ± 245.92 ml in controls when duration of labour was >10hrs.(p>0.05).

Graph 2: Distribution of cases according to birth weight and  APGAR at 5 min.

In group A, 9% of cases had birth weight <2.5 kg whereas 12% had <2.5 kg birth weight in group B. (p>0.05)  In group A, mean APGAR was 9.53 ± 0.92 whereas 9.61 ± 0.87 in group

1. (p>0.05)

TABLE 8: Distribution of cases according to sex of the baby

In group A, 59% of cases had male baby whereas 46% had male in group B. (p<0.05)

In our study, Maximum 60% of cases had age between 19 – 25 yrs in group A followed by 35% were in 26 – 30 yrs whereas minimum 1% had >35 yrs age. Maximum 63% of cases had age between 19 – 25 yrs in group A followed by 28% were in 26 – 30 yrs whereas minimum 4% had >35 yrs age. Mean age was 24.71 ± 3.84 yr in group A whereas 25.15 ± 4.23 yr in group B. Similarly Shazia Rafiq et al. (2023)¹¹ found that a total number of 262 pregnant women aged 20-40 years, having gestational age 37 to 42 weeks were analyzed. The mean age was 31.28±4.96 years.

In group A, maximum 49% of cases were multigravida followed by 40% were primigravida whereas in group B, maximum 47% of cases were primigravida followed by 43% were multigravida. Similarly Ann Symirna M.J et al. (2023)¹² found that 66.5% were primi.

In group A, maximum 64% of cases were in 37 – 40 wks of gestation followed by 33% were <37 wks whereas minimum 3% were >40 wks. In group B, maximum 77% of cases were in 37 – 40 wks of gestation followed by 18% were <37 wks whereas minimum 5% were >40 wks. Similarly Shazia Rafiq et al. (2023)¹¹ found that mean gestational age at the time of delivery was 39.74±1.62 weeks.

In our study, group A mean SBP was 117.18 ± 7.61 mm of Hg whereas 118.20 ± 8.47 mm of Hg in group B. In group B, mean DBP was 76.74 ± 5.55 mm of Hg whereas 77.46 ± 5.33 mm of Hg in group B. In group A, post delivery mean SBP was 116.92 ± 7.48 mm of Hg whereas 120.04 ± 9.07 mm of Hg in group B. (p<0.05), In group B, post delivery mean DBP was 77.06 ± 5.66 mm of Hg whereas 78.2 ± 5.00 mm of Hg in group B. (p<0.01)

In group A no indication of induction was seen whereas in group B, 56% of cases were induced due to elective or patient request followed by 18% were had PROM / Leaking PV and 21% had due dated pregnancy. (p<0.05). Bid Kumar et al. (2021)¹³ found that small for gestational age (SGA) or fetal growth restriction (FGR) (18%), spontaneous rupture of membrane (17%), reduced fetal movement (16%), prolonged pregnancy (15%), and diabetes (13%).

In our study, in group A no induction was seen whereas in group B, 77% of cases were induced by inj. Oxytocin followed by 21% were by mixed method either dianoprost gel + oxytocin or misoprostol + oxytocin and only 2% used dianoprost gel (p<0.05). Similarly Shazia Rafiq et al. (2023)¹¹ found that Comparison of the post-partum hemorrhage between modes of labour showed that 28 (21.4%) undergoing induced induction and 10 (7.6%) in spontaneous labour had post-partum hemorrhage (p=0.002).

In post delivery maximum 44% controls and 48% cases had 9 – 10.9 gm/dl post delivery Hb. In group A, post delivery mean Hb was 9.91 ± 1.66 mg/dl whereas 10.48 ± 1.56 mm of Hg in group B. (p<0.01). Similarly Romana Brun et al. (2019)¹⁴ in their study observed that women with induction of labor had a significantly reduced decrease in hemoglobin after delivery.

In our study, mean blood loss was lower in cases 299.09 ± 161.39 ml in comparison to controls 310.83 ± 241.6 ml when duration of labour was <6hr. In duration of labour 6-10 hr the mean blood loss was higher in cases 341.0 ± 159.68 whereas 266.92 ± 243.56 in controls and the difference was statistically significant. (p<0.05). Mean blood loss in cases was 313.33 ± 162.60 ml whereas 286.0 ± 245.92 ml in controls when duration of labour was >10hrs.(p>0.05). Similarly Q.-J. ZHANG et al. (2022)¹⁵ The induction of the labor group had a significantly longer total duration of labor (9.37±5.37 vs. 8.82±5.13 h; p<0.001) more postpartum blood loss (219.18±188.32 vs. 199.95±124.69 mL; p=0.01) and a significantly higher incidence of severe postpartum hemorrhage (PPH) com paring to the spontaneous onset of labor group [0.8% (16/2007) vs. 0.33% (8/2361); p=0.041].

In group A, 9% of cases had birth weight <2.5 kg whereas 12% had <2.5 kg birth weight in group B. (p>0.05) and In group A, mean APGAR was 9.53 ± 0.92 whereas 9.61 ± 0.87 in group B. (p>0.05). Also Q.-J. ZHANG et al. (2022)¹⁵ found that no significant difference was found in the neonatal outcomes. Also Romana Brun et al. (2019)19 observed that Secondary maternal and neonatal outcomes were unaffected.

Blood loss was comparatively higher in the induction category than in spontaneous delivery, and more bleeding occurred when the induction delivery interval was high. Visual estimation of blood loss often underrates the amount of blood lost, so a quantitative method has to be chosen to estimate accurate blood loss. Blood loss after delivery must be carefully assessed early to reduce maternal morbidity and mortality. Faster the action of the inducing agent, the shorter the induction delivery interval, the sooner the delivery, and the lesser the bleeding.

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