The placenta forms the most important link between the developing fetus and mother. The normal situation of the placenta is vital for appropriate growth and development of the fetus. Once there is a change in placental location or architecture, the outcome of pregnancy (maternal and fetal) is altered. The placenta is usually situated in the upper uterine segment usually near the fundus on the posterior wall of the uterus and less frequently located on the anterior wall. Sometimes for other causes or reasons, the placental position may alter; lying wholly or partially in the lower uterine segment resulting in placenta previa (or praevia). The incidence is approximately 4 to 5 per 1000 pregnancies(3'4). The risk factors associated with it are well known and include age, parity, multiple gestation, endometrial damage following therapeutic termination in first trimester (6 fold increase) and previous caesarean section ( 1.9% increased risk in previous I LSCS and 4.1% increased risk in previous 2 LSCS).(5)Accreta occurs in 3.3% of unscarred uterus, in 11 % of patients with previous one caesarean section & 40% in patients with previous 2 LSCS.(6'7) Smokers have more than two times risk than non-smokers. In patients with congenital malformation of the fetus there is twice common risk of placenta previa. In patients with abnormal presentation, 30-35% cases have associated placenta previa (9m I)

Placenta previa complicates 0.3-1.5% of the pregnancies and it may lead to significant maternal morbidity and even death. It is also associated with poor neonatal outcome includes preterm delivery, low birth weight and perinatal death. Placenta previa invading the uterine wall becomes morbidly adherent placenta (MAP) in form of placenta accrete, increta and percreta. MAP can result in life threatening hemorrhage, disseminated intravascular coagulation and death.[1]

The rising trend of caesarean section has led to dramatic increase in incidence of placenta Previa and MAP in last few decades.[2] Ultrasound has good diagnostic accuracy in diagnosis of placenta previa but in some patients, MAP is diagnosed intraoperatively and hence has catastrophic outcomes.[3]

Pakistan is fifth most populous country with maternal mortality of 178/100,000. Obstetric hemorrhage is major contributor of these maternal deaths with placenta previa along with MAP now being the major culprits. [4] Morbidity with placenta previa and MAP can significantly be reduced if diagnosed antenatally. This will ensure arrangement in properly equipped hospital with multidisciplinary approach and availability of blood transfusion, anaesthesia, ICU and neonatal facilities. This is extremely challenging in low resource countries where blood transfusion and operative services are not available at periphery where most of the population is residing. Repeated multiple studies which emphasize the underlying cause of ante and postpartum hemorrhage will go a long way in sensitizing people at government level to improve facility at primary, secondary and tertiary level. The aims to determine the risk factors and fetomaternal outcomes of placenta previa among pregnant women.

The placenta forms the most important link between the developing fetus and mother. The normal situation of the placenta is vital for appropriate growth and development of the fetus. Once there is a change in placental location or architecture, the outcome of pregnancy (maternal and fetal) is altered. The placenta is usually situated in the upper uterine segment usually near the fundus on the posterior wall of the uterus and less frequently located on the anterior wall. Sometimes for other causes or reasons, the placental position may alter; lying wholly or partially in the lower uterine segment resulting in placenta previa (or praevia). The incidence is approximately 4 to 5 per 1000 pregnancies(3'4). The risk factors associated with it are well known and include age, parity, multiple gestation, endometrial damage following therapeutic termination in first trimester (6 fold increase) and previous caesarean section ( 1.9% increased risk in previous I LSCS and 4.1% increased risk in previous 2 LSCS).(5)Accreta occurs in 3.3% of unscarred uterus, in 11 % of patients with previous one caesarean section & 40% in patients with previous 2 LSCS.(6'7) Smokers have more than two times risk than non-smokers. In patients with congenital malformation of the fetus there is twice common risk of placenta previa. In patients with abnormal presentation, 30-35% cases have associated placenta previa (9m I)

Placenta previa complicates 0.3-1.5% of the pregnancies and it may lead to significant maternal morbidity and even death. It is also associated with poor neonatal outcome includes preterm delivery, low birth weight and perinatal death. Placenta previa invading the uterine wall becomes morbidly adherent placenta (MAP) in form of placenta accrete, increta and percreta. MAP can result in life threatening hemorrhage, disseminated intravascular coagulation and death.[1]

The rising trend of caesarean section has led to dramatic increase in incidence of placenta Previa and MAP in last few decades.[2] Ultrasound has good diagnostic accuracy in diagnosis of placenta previa but in some patients, MAP is diagnosed intraoperatively and hence has catastrophic outcomes.[3]

Pakistan is fifth most populous country with maternal mortality of 178/100,000. Obstetric hemorrhage is major contributor of these maternal deaths with placenta previa along with MAP now being the major culprits. [4] Morbidity with placenta previa and MAP can significantly be reduced if diagnosed antenatally. This will ensure arrangement in properly equipped hospital with multidisciplinary approach and availability of blood transfusion, anaesthesia, ICU and neonatal facilities. This is extremely challenging in low resource countries where blood transfusion and operative services are not available at periphery where most of the population is residing. Repeated multiple studies which emphasize the underlying cause of ante and postpartum hemorrhage will go a long way in sensitizing people at government level to improve facility at primary, secondary and tertiary level. The aims to determine the risk factors and fetomaternal outcomes of placenta previa among pregnant women.

Study design/Experiment design interpretation: Prospective, Observational institutional based study

Study setting and timelines parameters: The study will start with submission of research proposal. After receiving ethical committee approval the data collection was done for the next 12 month. Analysis of data was done for another 2-3 months & report writing was done for another 2-3 month.

Place of study: Dept. of Obstetrics & Gynaecology

Study population research work: NRS Medical College & Hospital provides services to patient from Kolkata & also those who are referred from peripheral centre. Patient with the fulfilled inclusion and exclusion criteria was included in the study.

Sample size/design: From previous year data records the average admission of placenta previa patient in their department is 6/week i.e 312/year. I will do data collection thrice weekly so my study sample size was 133.

INCLUSION CRITERIA:

1. Singleton pregnancy with placenta previa (confirmed by ultrasonography)
2. Those patients who came with history of painless bleeding per vagina after 28 weeks of gestation were hospitalized.
3. Those cases who were admitted in emergency without ultrasound, confirmation of placenta previa was done, by examining the placenta after delivery by looking for tongue shaped extension which was not covered by the fetal membrane were included in the study.
4. Those patient admitted in emergency with severe painless bleeding per vagina without any previous ultrasound, if the patient was in shock, resuscitative measures being carried out in the form of IV fluids, blood transfusion and antibiotics to prevent infection. Vaginal examination was carried out under "double set up" condition, if turns out to be placenta previa caesarean section was preferred to vaginal delivery except in minor degree when vaginal deliver appeared-to-he-safer for mother and fetus. After caesarean section or vaginal delivery, placenta was examined to confirm the diagnosis of placenta previa those also included in study.

EXCLUSION CRITERIA:

1.Multiple pregnancies

2. Significant maternal medical disorders not related to pregnancy

Study Variables: Maternal age, previous caesarean section, previous history of placenta previa, induced abortions, gestational age etc.

Statistical Analysis:

For statistical analysis, data were initially entered into a Microsoft Excel spreadsheet and then analyzed using SPSS (version 27.0; SPSS Inc., Chicago, IL, USA) and GraphPad Prism (version 5). Numerical variables were summarized using means and standard deviations, while categorical variables were described with counts and percentages. Two-sample t-tests, which compare the means of independent or unpaired samples, were used to assess differences between groups. Paired t-tests, which account for the correlation between paired observations, offer greater power than unpaired tests. Chi-square tests (χ² tests) were employed to evaluate hypotheses where the sampling distribution of the test statistic follows a chi-squared distribution under the null hypothesis; Pearson's chi-squared test is often referred to simply as the chi-squared test. For comparisons of unpaired proportions, either the chi-square test or Fisher’s exact test was used, depending on the context. To perform t-tests, the relevant formulae for test statistics, which either exactly follow or closely approximate a t-distribution under the null hypothesis, were applied, with specific degrees of freedom indicated for each test. P-values were determined from Student's t-distribution tables. A p-value ≤ 0.05 was considered statistically significant, leading to the rejection of the null hypothesis in favour of the alternative hypothesis.

Table 1: Distribution of Obstetric Code, Previous Abortion, Previous H/O C-Section, Grade Of Placenta Previa, Fetal Presentation and Multiple Gestation

Table 2: Distribution of mean Gestational Age at Delivery

In our study, 31 (23.0%) patients were Primi Gravida and 102 (76.7%) patients were Multi Gravida. The value of z is 7.158. The value of p is < .00001. The result is significant at p < .05. In our study, 46 (34.6%) patients had h/o Previous Abortion. The value of z is 5.0277. The value of p is < .00001. The result is significant at p < .05. In our study, 88 (66.2%) patients had Previous H/O C-Section. The value of z is 5.273. The value of p is < .00001. The result is significant at p < .05. In our study, 41 (30.8%) patients had Grade I placenta previa, 21 (15.8%) patients had Grade II A placenta previa, 12 (9.0%) patients had Grade II B placenta previa, 30 (22.6%) patients had Grade III placenta previa and 29 (21.8%) patients had Grade IV placenta previa. The value of z is 4.4515. The value of p is < .00001. The result is significant at p < .05. In our study, 21 (15.8%) patients had Breech presentation, 112 (84.2%) patients had Cephalic presentation. The value of z is 11.1591. The value of p is < .00001. The result is significant at p < .05. In our study, 124 (93.2%) patients had Singleton pregnancy, 9 (6.8%) patients had Twin pregnancy. The value of z is 14.1022. The value of p is < .00001. The result is significant at p < .05. In our study, 4 (3.0%) patients underwent Lower Segment Hysterectomy, 115 (86.5%) patients underwent LSCS, 3 (2.3%) patients underwent Subtotal Hysterectomy, 11 (8.3%) patients delivered Vaginally. The value of z is 13.6877. The value of p is < .00001. The result is significant at p < .05.

In our study, 98 (73.7%) patients required Blood Transfusion. The value of z is 7.7256. The value of p is < .00001. The result is significant at p < .05. In our study, 3 (2.3%) patients needed Bladder Rent Repair and 16 (12.0%) patients had PPH. The value of z is 13.7113. The value of p is < .00001. The result is significant at p < .05. In this table showed that the mean Gestational Age at Delivery (In Wks) (mean±s.d.) of patients was 35.7368± 2.6654. In above table showed that the mean Gestational Age at Delivery (In Wks) (mean±s.d.) of patients was 35.7368± 2.6654. In above table showed that the mean Apgar score (mean±s.d.) of babies was 6.6667± 1.5173. In our study, babies of 129 (97.0%) patients were Alive and babies of 4 (3.0%) patients were dead. The value of z is 15.3285. The value of p is < .00001. The result is significant at p < .05. In our study, babies of 63 (48.8%) patients had Apgar score in 5 min <7 and babies of 66 (51.2%) patients had Apgar score in 5 min ≥7. The value of z is 0.3735. The value of p is .71138. The result is not significant at p <.05.

Our study showed that, lower number of patients were Primi Gravida [31 (23.0%)] & it was statistically significant (p<0.0001) (Z=7.158).

Yadava PA et al [5](2019) placenta previa is defined as placenta that is implanted somewhere in the lower uterine segment either over or very near the internal cervical os. Placenta previa and coexistent accrete syndromes contribute substantively to maternal and perinatal morbidity and mortality. The total number of deliveries performed during the study period was 16330, of them, 88 cases were placenta previa. Thus, the prevalence of PP was 0.53%. Multiparity was one of the etiological factors in 84.09%, whereas previous LSCS was 47.73%, previous H/O D and E was 14.73%, previous H/O placenta previa was 7.95%.

It was found that, lower number of patients had [46 (34.6%)] Previous Abortion it was statistically significant (p<0.0001) (Z=5.0277). Most of the patients had [88 (66.2%)] Previous H/O C-Section it was also statistically significant (p<0.0001) (Z=5.273). Most of the patients had Grade I placenta previa [41 (30.8%)] it was statistically significant (p<0.0001) (Z=4.4515).

Rani K et al [6](2020) placenta accreta spectrum (PAS) is an entity where abnormal trophoblastic invasion of placenta occurs into myometrium of uterine wall either partially or totally. Maximum patients were in age group of 30-34 years (48.83%) and were third gravida (39.53%). 34.88 % cases had history of previous 2 LSCS (lower segment caesarean section) and in 67.44% it was associated with placenta previa. 67.44% had postpartum haemorrhage (PPH) with 48.83% unbooked cases. 41.18% cases went into hemorrhagic shock with 34.38

% falling into unbooked category. 69.76% had intensive care unit (ICU) admission due to various indications out of which 83.33% were unbooked and 16.67% were booked.

We showed that, lower number of patients had [21 (15.8%)] Breech presentation it was statistically significant (p<0.0001) (Z=11.1591). Most of the patients had [124 (93.2%)] Singleton pregnancy which was statistically significant (p<0.0001) (Z=14.1022). Most of the patients underwent [115 (86.5%)] LSCS which was statistically significant (p<0.0001) (Z=13.6877).

Ndomba M et al [7](2021) examined that placenta Praevia (PP) is frequently associated with severe maternal bleeding leading to an increased risk for adverse outcome of mother and infant. This study aims to determine the prevalence, and to evaluate potential risk factors and respective outcomes of pregnancies with PP in Lubumbashi, Democratic Republic of Congo. Data were retrospectively collected from patients diagnosed with PP at 4 hospitals in Lubumbashi between January 2013 and December 2016. All women who gave birth to singleton infants were studied. Differences between women with PP and without PP were evaluated.

We observed that, higher number of patients required [98 (73.7%)] Blood Transfusion which was statistically significant (p<0.0001) (Z=7.7256). More number of patients had [114 (85.7%)] no Maternal Morbidity which was statistically significant (p<0.0001) (Z=13.7113), only babies of 4 patients were Died.

Zhou C et al [8](2022) found that to analyze the risk factors associated with the development of placenta praevia (PP) in first-time pregnant patients and to observe the perinatal clinical outcomes of patients. The clinical data of 112 pregnant women with PP (PP group) and 224 pregnant women with normal placental position (general group) who delivered in their hospital from August 2016 to August 2021 were retrospectively analyzed. Baseline demographic data such as age, gestational week, uterine history, assisted reproductive technology use, pregnancy comorbidities, pre-pregnancy body mass index (BMI), smoking, alcohol consumption, placental position, educational level, work were collected from both groups, and logistic regression models were used to analyze the factors influencing the occurrence of PP in patients with first pregnancy.

It was found that, the mean Age of patients was [25.2932± 4.1098], Gestational Age at Delivery (In Wks) of patients was [35.7368± 2.6654], Birth Weight (in Kgs) of babies was [2.2466± .5274] and Apgar score of babies was [6.6667± 1.5173].

Placenta previa, whether found fortuitously by ultrasound or with the clinical emergency of maternal hemorrhage carries significant maternal and fetal risk. Accurate diagnosis, judicious expectant management with blood transfusion as required and timely delivery can lead to the most favourable outcome. The current study suggested there is association between advancing maternal age, gravidity parity previous abortion and cesarean sections as increased risk factors for placenta previa. Anticipation of the clinical complications like PPH and conservative management may avoid serious consequences. 

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