|Year : 2022 | Volume
| Issue : 4 | Page : 371-378
Prevalence, outcomes, and predictors of antepartum hemorrhage due to placenta previa in Nigeria
Johnpaul E Nnagbo1, Matthew I Eze2, Joseph O Ezugworie3, George O Ugwu2, Emeka I Iloghalu2, Eziamaka P Ezenkwele2, Elija N Onwudiwe2, Onyemaechi S Okoro2, Leonard O Ajah2, Emmanuel O Izuka2, Charles O Adiri2, Peter O Nkwo2, Emmanuel O Ugwu2, Chukwuemeka A Iyoke2, Euzebus C Ezugwu2, Polycarp U Agu2
1 Department of Obstetrics and Gynaecology, University of Nigeria Teaching Hospital, Ituku-Ozalla, Nigeria
2 Department of Obstetrics and Gynaecology, College of Medicine, University of Nigeria, Ituku-Ozalla, Nigeria
3 Department of Obstetrics and Gynaecology, College of Medicine, University of Nigeria, Ituku-Ozalla, Nigeria; Department of Anatomy, College of Medicine, University of Nigeria, Enugu Campus, Enugu State, Nigeria
|Date of Submission||27-Feb-2022|
|Date of Decision||21-May-2022|
|Date of Acceptance||23-Jul-2022|
|Date of Web Publication||22-Sep-2022|
Johnpaul E Nnagbo
Department of Obstetrics and Gynaecologys, University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu State, Enugu
Source of Support: None, Conflict of Interest: None
Background: Despite the enormous burden of antepartum hemorrhage (APH) due to placental previa, there are not much recent data on prevalence, outcomes, and predictors of this major obstetric condition in low-resource settings. Objectives: The objectives of this study are to determine the prevalence, outcomes, and predictors of APH due to placenta previa in Enugu, South-East Nigeria. Materials and Methods: It was a retrospective review of pregnant women admitted to the University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu, Nigeria, with a diagnosis of APH due to placenta previa from January 1, 2010 to January 31, 2019. Relevant data such as biodata, obstetrics characteristics, and management protocols were extracted from eligible case notes retrieved from the Medical Records Department of the hospital. Results: Of the 6001 pregnant women managed, 91 had APH due to placenta previa, giving a prevalence rate of 1.5% (91/6001). In terms of maternal and fetal outcomes, no maternal death or delivery due to fetal distress was recorded. Thirty-seven (40.7%) women had primary postpartum hemorrhage (PPH), 1.1% had obstetric hysterectomy due to PPH, 45.1% had blood transfusion, 51% were delivered due to intractable APH, 98.9% of the babies were delivered alive, 39.6% required admission into newborn special care unit, and 40.7% had babies with low birth weight. The predictors of APH due to placenta previa were low socioeconomic status (P = 0.011, odds ratio [OR] = 0.15, 95% confidence interval [CI]: 0.03–0.64), high parity (P = 0.032, OR = 6.61, 95% CI: 1.18–37.02), adopting conservative management (P = 0.004, B = 2.765, OR = 0.06, 95% CI: 0.01–0.40), and unbooked status (P = 0.018, B = 2.724, OR = 15.24, 95% CI: 1.61–144.16). Conclusion: The prevalence of PPH in the study population is high and the outcome is favorable. It is predicted by the unbooked status, multiparity, and adopting conservative management. The study findings should guide obstetricians in counseling and managing women with APH due to placenta previa.
Keywords: Antepartum hemorrhage, outcome, placenta previa, predictor
|How to cite this article:|
Nnagbo JE, Eze MI, Ezugworie JO, Ugwu GO, Iloghalu EI, Ezenkwele EP, Onwudiwe EN, Okoro OS, Ajah LO, Izuka EO, Adiri CO, Nkwo PO, Ugwu EO, Iyoke CA, Ezugwu EC, Agu PU. Prevalence, outcomes, and predictors of antepartum hemorrhage due to placenta previa in Nigeria. Int J Med Health Dev 2022;27:371-8
|How to cite this URL:|
Nnagbo JE, Eze MI, Ezugworie JO, Ugwu GO, Iloghalu EI, Ezenkwele EP, Onwudiwe EN, Okoro OS, Ajah LO, Izuka EO, Adiri CO, Nkwo PO, Ugwu EO, Iyoke CA, Ezugwu EC, Agu PU. Prevalence, outcomes, and predictors of antepartum hemorrhage due to placenta previa in Nigeria. Int J Med Health Dev [serial online] 2022 [cited 2022 Oct 1];27:371-8. Available from: https://www.ijmhdev.com/text.asp?2022/27/4/371/356626
| Introduction|| |
Antepartum hemorrhage (APH) is bleeding from or in the genital tract after the age of viability and prior to delivery. It is usually of great concern to the intending mother due to perceived detrimental impact on the fetus.
Globally, APH due to placenta previa is known to complicate 3–5% of pregnancies and is one of the leading causes of maternal, fetal, and neonatal morbidities and mortalities.
APH due to placenta previa tends to be more profuse and frequent toward term when uterine contraction and increased blood flow to the uterus up to 500–700 mL/min complicates the condition., This simply shows that in few minutes maternal exsanguination could occur in the event of APH. Placentae abnormally sited at the lower uterine segment (low-lying) or sitting on the internal os (placenta previa) are prone to painless, unpredictable, bright red vaginal bleeding of varying degrees. The first episode is usually mild but subsequent ones could be severe, life-threatening, and when intractable lead to preterm cesarean delivery, maternal anemia, multiple blood transfusions, consumptive coagulopathy, obstetric hysterectomy, renal failure, postpartum hemorrhage, prolonged hospital stay, and maternal and perinatal mortalities.,,
APH due to placenta previa contributes 20–90% of cases in various studies around the world,,,,,, but a pooled prevalence of 51.6% was reported in a meta-analysis. This wide range of figure has been attributed to various factors such as diagnostic criteria, placental location, maternal age, and the type of placenta previa.,,,
In Nigeria, although the incidence of placenta previa ranges between 0.84% and 2.6%,,,,, the prevalence of APH due to placenta previa ranges between 1.3% and 1.9%,,, depending on the number of antenatal admissions recorded. These figures are quite high and may be higher with the recent rises in the cesarean section and in-vitro fertilization rates which are known causes of placenta previa.
Typically, APH due to placenta previa warrants immediate admission and stabilization. Those with intractable hemorrhage are delivered as emergency, whereas those stabilized are further managed in the hospital conservatively until they reach a gestational age (GA) of 37 weeks. The aim of the conservative management is to improve the fetal salvage without compromising maternal health. This management protocol was popularized by MacAfee, and Johnson in 1945 and since then it has undergone some modifications in order to suite individual obstetric units and to improve overall outcomes of the pregnancy. For a patient to be selected for conservative management, the GA should be <37 weeks, Hb should be greater than or equal to 10 g/dL, vaginal bleeding must have stopped, and the fetal condition must be reassuring.
APH due to placenta previa remains a challenge to obstetricians globally because it is unpredictable, brisk, and has the potential to compromise the fetus or the mother. As a result of this, effort is currently being made to discover predictive factors that can suggest those who would bleed, so as to mount closer surveillance by admitting them in hospitals. To this end, various studies have suggested certain predictors such as advanced maternal age, previous history of dilatation and curettage, previous cesarean section, history of bleeding early in gestation and living far from hospitals, previous history of uterine artery embolization, placenta characteristics, complete placenta previa, anterior placenta, presence of echo-free space in the placental edge, short cervical length, and partial absence of the overlying myometrium.,,, However, evidence in support of these predictors is yet to be verified in more elaborate studies with larger sample sizes and superior study designs.
The outcome of pregnancies complicated by placenta previa has been reviewed by many researchers in Nigeria with evidence generally showing low maternal mortality and high perinatal mortality rates, with some studies showing high blood transfusion and peripartum hysterectomy rates.,,,, However, in-depth studies are still lacking on the prevalence, outcomes, and predictors of APH due to placenta previa in Nigeria. These data are useful in properly counseling patients who may present with APH due to placenta previa in Nigeria and other low- and middle-income countries. This study therefore aims to determine the prevalence, outcomes, and predictors of APH due to placenta previa at the University of Nigeria Teaching Hospital (UTNH), Enugu, South-East Nigeria.
| Materials and Methods|| |
This was a retrospective review of all the patients’ records who were admitted for APH due to placenta previa into the UNTH via the Emergency Unit or via the labor ward of the hospital from January 2010 to December 2019.
The UNTH is almost the largest tertiary hospital in the southeastern Nigeria. It is located 25 km away from Enugu, the capital of Enugu State in a boundary town called Ituku-Ozalla. It is a referral center for most obstetrics and gynecological problems in the region and usually receives patients from peripheral private and general hospitals at Awgu, Udi, and Agbani. It also receives patients occasionally from some parts of Ebonyi, Abia, Imo, Anambra, and Benue States, which are states sharing boundaries with the Enugu State. The UNTH has five obstetrics and gynecology units with up to 36 consultants managing the units. Antenatal care (ANC) clinics are conducted from Monday to Friday of every week, whereas the booking clinics are only conducted twice in a week: Mondays and Fridays. Each clinic is led by at least a consultant who reviews high-risk obstetrics patients, whereas the low-risk patients are seen by mid-wives and the resident doctors. On an average, in the ANC, 15 patients are seen each week. In emergencies, patients are admitted into the labor ward on consultant-led decisions from the Emergency Unit or from the ANC clinic. It attends to about 2500 deliveries annually, and up to 506 of these women are delivered through the cesarean section. Elective cesarean section accounts for 41.2% of the cesarean sections. However, recent data show that the delivery rate is now about 1000 per annum with the cesarean section rate of 25.7%.
The hospital’s Newborn Special Care Unit (NBSCU) has 20 cots and 15 incubators and is located adjacent to the labor ward. The NBSCU has four neonatologists who guide the resident doctors in the care of critically ill newborns admitted into the unit. The unit receives newborns from within and outside the hospital. Babies were admitted into the NBSCU when the neonatologist or senior resident doctors make a diagnosis requiring admission.
All the medical records of the patients admitted and managed with diagnosis of APH due to placenta previa at the hospital during the period under review were included in the study. In-depth study of all the records of APH due to placenta previa was done.
Before the commencement of the study, ethical approval was obtained from the Ethical Research Committee of UNTH Ituku-Ozalla, and written permission was obtained from the Medical Records Department of the UNTH to enable us have access to the medical records of all the eligible patients.
A proforma was designed to enable data collection from the medical records. The proforma contained the basic sociodemographic characteristics, obstetrics characteristics, and outcome variables. The sociodemographic characteristics included age, parity, level of education, and husband’s occupation. Obstetrics characteristics included GA on admission, diagnosis of placenta previa, method of diagnosis, admitted for conservative management, delivered on the same day of admission, mode of delivery, intrauterine fetal death on admission or during conservative management, number of days from admission to delivery, number of pints of blood transfused pre-op, intra-op, and post-op, cadre of surgeon who delivered, intra-op blood loss in milliliters, hysterectomy, adherent placenta, duration of hospital stay in days, number of maternal deaths, NBSCU admission, indication for admission, number of babies discharged from the NBSCU, and number of babies that died in the NBSCU. APH due to placenta previa was diagnosed when a patient had vaginal bleeding from ≥ 28 weeks, and transvaginal ultrasound (TVS) or transabdominal ultrasound performed by a consultant radiologist demonstrated lower edge of placenta within 2 cm from the internal os.
Data analysis was both descriptive and inferential using IBM SPSS version 20.0. Patients with incomplete data were excluded from the analysis, whereas the rest were analyzed. Descriptive statistics was used to analyze the sociodemographic variables. Proportions were presented in percentages and frequencies. Some continuous variables such as age, GA, days from admission to delivery (in h), and volume of intra-op blood loss as postpartum hemorrhage (PPH, in mL) were dichotomized as categorical variables, in addition to other categorical variables, and analyzed using the χ2 test. The predictors were determined using binary logistic regression. P-value of less than 0.05 was considered statistically significant.
| Results|| |
From 2010 to 2019, a total of 6250 pregnant women were admitted to the UNTH for delivery, but only 6001 medical records were retrieved within the study period, showing a retrieval rate of 96.1% (6001/6250). The sociodemographic characteristics of the participants showed that the age ranged from 19 to 43 years with a mean age of 31.4 ± 5.71 years. Age also showed bimodal distribution with those aged 30–34 and 35–39 years occurring at 31.9% each. A great proportion of women (40 [44%]) were admitted at or above 37 weeks (term) GA, 30 (33.0%) from 28 to 33+6 weeks gestational (severe preterm), and 21 (23.0%) were admitted from 34 to 36+6 weeks (moderate preterm). The details of other basic characteristics are as stated in [Table 1]. Of the 6001 pregnant women whose medical records were reviewed, 91 had APH due to placenta previa, with a prevalence rate of 1.5% (91/6001).
[Table 2] shows the obstetrics characteristics of women who had APH due to placenta previa. Of the 91 women who had APH due to placenta previa, 86 (94.5%) were conceived spontaneously, whereas 5 (5.5%) were conceived through the assisted reproductive technique (ART). Majority of the cases (82 [90.1%]) were multigravida, whereas only 9 (9.9%) were primigravida. Similarly, majority of the cases (45 [49.5%]) were delivered at term (≥37 weeks), whereas 29 (31.9%) and 17 (18.7%) were delivered at 34–36+6 and 28–33+6 weeks, respectively. The GA at delivery ranged from 25 to 42+6 weeks, with a mean of 35.54 ± 5.71 weeks. Types I, II, III, and IV placenta previa were diagnosed in 15 (16.5%), 22 (24.2%), 30 (32.9%), and 24(26.4%), respectively, as shown in [Figure 1].
|Table 2: Obstetrics and gynecological characteristics of participants with APH due to placenta previa|
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[Table 3] shows that out of the 91 cases of APH due to placenta previa, only 29 (31.9%) had conservative management before cesarean delivery, whereas most (62 [68.1%]) had immediate cesarean delivery at presentation. Thirty-seven (40.7%) had PPH (≥ 1000 mL), whereas the greater proportion (54 [59.3%]) had no PPH. Forty-one (45.1%) had blood transfusion. There was only one case of hysterectomy 1 (1.1%), whereas 90 (98.9%) had no hysterectomy. While assessing the reason for delivery, uncontrollable bleeding was the indication for delivery in 51 (56%), whereas none of the cases was delivered as a result of fetal distress. Only 37 (40.7) cases were delivered with low birth weight (LBW) <2.5 kg, whereas 54 (59.3%) had birth weight ≥2.5 kg. There was one case of stillbirth at delivery, whereas 90 (98.9%) were delivered alive. Of all the newborns delivered, 36 (39.6%) had NBSCU admission, whereas the greater proportion of cases 55 (60.4%) were not admitted. There was no maternal death recorded in this review.
|Table 3: Maternal and fetal outcomes of APH due to placenta previa at the UNTH|
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The predictors of APH due to placenta previa following logistic regression analysis included booking status, parity, socio-economic status, and conservative management (P < 0.05). Details are shown in [Table 4].
| Discussion|| |
The prevalence of APH due to placenta previa of 1.5% as recorded in this study was high when compared with similar studies from Northern Nigeria and Mumbai India where prevalences of 0.36% and 0.835% were reported, respectively., This high figure reported in our study may be due to the fact that the study center was a major referral facility for such cases. However, the figure is comparable to 2.0% prevalence rate reported at the University of Lagos Teaching Hospital, Idi-Araba, Nigeria. The implication of reporting high prevalence of APH due to placenta previa is that efforts need to be channeled toward reducing the incidence of placenta previa which is the major predisposing factor.
Patients admitted with APH due to placenta previa are either managed conservatively if remote from age of lung maturity or delivered immediately if above age of lung maturation or when there is intractable hemorrhage. As shown by our study, 31.9% of the participants who had conservative management were due to presentation before the age of lung maturation. Similar practice is done in another center. Those who were delivered immediately by the caesarean section were those who had attained age of lung maturity at the time of presentation with APH.
Though only 40.7% of the participants had PPH, this is a remarkable finding worthy of note, as PPH remains a major contributor to maternal mortality globally. This rate is higher than 24.2% and 36% reported in similar studies from Northern Nigeria and Mumbai India, respectively., However, the figure is comparable to 42.5% of PPH following APH due to placenta previa reported by Gupta and co-workers from India. The reason for the high rate of PPH in this study may be due to other risk factors of PPH that were present in the significant proportion of the participants such as multiparity and major degree placenta previa.
The obstetric hysterectomy rate of 1.1% as seen in our study is considered low since it is lower than rates reported in the previous studies.,,,, This low rate may be attributed to the fact that we had lower proportion of women with PPH in the study population. In addition, the use of parenteral oxytocics as recommended by the WHO and application of uterine packing as an intervention for treating PPH were practiced in the study center and may have contributed in reducing the obstetric hysterectomy rate.,
Although the high proportion of patients who were delivered by the cesarean section on account of uncontrollable bleeding was concerning, the rate was lower than that reported by Hasegawa et al. who documented a rate of 66.7%. This could be accounted by the significant proportion of participants who had major degrees of placenta previa which are known to present with more severe bleeding compared with minor degrees of placenta previa.
The high rate of overall blood transfusion was not surprising as majority of the participants had major degrees of placenta previa known to cause significant bleeding. The rate was obviously higher than 18.3% reported in an Indian study and 33.3% reported by Ezechi et al. in Lagos, Nigeria. The difference in the reported transfusion rate may be due to the high prevalence of PPH and major degree previa in the current study.
Maternal mortality remains a devastating obstetrics outcome globally, but none was reported in this study. This finding is not surprising as general trends of maternal mortality in this center revealed a progressive decline,, showing that there has been significant improvement in the obstetric care services. Similarly, there was no maternal mortality due to APH from placenta previa reported in a study from northern Nigeria and that from Mumbai India. On the contrary, two maternal deaths due to severe hemorrhagic shock from placenta previa occurred in a similar study in western Nigeria over a decade ago.
The LBW rate of 40.7% reported in this study is worthy of note, in spite of the fact that a significant proportion of the fetuses were delivered with term birth weights. This rate is higher than 13.0%, 33.3%, and 35.1% reported in similar studies from Northern Nigeria, Bangkok, and western Nigeria, respectively.,, This may be explained by the significant proportion of the patients who delivered at <37 weeks GA. However, this result is comparable to 40% low birth rate reported in Mumbai, India.
Though APH due to placenta previa can cause fetal demise, our study revealed 98.9% live birth rate, with only one case of a fetus that was not delivered alive. This fetal death was as a result of the fact that the patient traveled from a far distance and was in hemorrhagic shock with her fetus in distress at presentation. This is not surprising as similar low newborn death rate at birth has been reported in another study.
The NBSCU admission rate of 39.6% was considered high because it was above the 16.9–30% figure reported in similar studies in Western Nigeria and India.,, This could be explained by the significant proportion of participants who were delivered at <37 weeks GA, when the NBSCU admission is most likely. However, it is lower than the admission rate of 50.6% reported by Long et al. in a similar study in China, in which 85% of the participants had preterm delivery.
Due to the risk of APH associated with placenta previa and the need to avert this, determining predictors of APH becomes necessary inpatient care. Some studies have suggested certain predictors of APH such as complete placenta previa, advanced maternal age, anterior placenta, presence of echo-free space in the placental edge, short cervical length, previous history of uterine artery embolization, partial absence of the overlying myometrium, previous history of dilatation and curettage, previous cesarean section, history of bleeding early in gestation, and living far from hospital.,,,
However, following a logistic regression analysis, our study showed that being unbooked predicts the risk of bleeding in women with placenta previa (P = 0.018, B= 2.724, odds ratio [OR] = 15.237, 95% confidence interval [CI]: 1.610–144.162). This means that those who have placenta previa and are unbooked are 15 times more likely to have APH when compared with those who are booked. This finding may be explained by the fact that booking for ANC enables the obstetrician to conduct ultrasound early for proper dating, enables risk assessment for placenta previa to be made early, provides opportunity for follow-up TVS for monitoring of placental migration, and rules out echo-free space in the placental edge, complete placenta previa, and anterior placenta which are known to cause sudden massive bleeding.,
In our study, being multiparous was identified as a predictor of APH (P = 0.032, B=1.888, OR=6.609, 95% CI: 1.180–37.016). This may be related to the fact that above 80% of the participants were multiparous, which has been associated with advanced maternal age and previous cesarean section reported to cause APH among women with placenta previa in a previous study. Another predictor of APH in our study is being of low socio-economic class (P = 0.011, B= -1.898, OR= 0.150, 95% CI: 0.035–0.642). The relationship between socio-economic status and risk of APH among women with placenta previa is not clear.
Furthermore, another predictor of APH in our study is adopting conservative management (P = 0.004, B= 2.765, OR=0.063, 95% CI: 0.010–0.403). This means that those who are managed conservatively are more likely to have APH. This may be explained by the fact that although conservative management of placenta previa offers the opportunity to control the triggers of bleeding such as uterine contraction using tocolytics and bed rest,, it does not completely remove the risk of bleeding when compared with those who had immediate cesarean section.
The major limitation of this study is in its retrospective design with some missing folders and data. It was also a one-center study which limits generalization of the study findings. Nevertheless, this study has provided an up-to-date overview of the prevalence, outcome, and predictors of APH due to placenta previa in Nigeria and other low-resource settings.
| Conclusion|| |
The prevalence of APH in the study population is high and the outcome is favorable. It is predicted by the unbooked status, multiparity, and adopting conservative management. The study findings should guide obstetricians in counseling and managing women with APH due to placenta.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Antepartum Haemorrhage. RCOG Green-Top Guideline. 2011;63:1-23.Available from: https://www.rcog.org.uk/guidance/browse-all-guidance/green-top-guidelines/antepartum-haemorrhage-green-top-guideline-no-63/
. [last accessed on May 15, 2021].
Calleja-Agius J, Custo R, Brincat MP, Calleja N Placental abruption and placenta previa. Eur Clin Obstet Gynecol 2006;2:121-7.
Placenta previa, placenta accreta and vasa previa. RCOG Information for You. 2018:1-6. Available from: https://www.rcog.org.uk/for-the-public/browse-all-patient-information-leaflets/placenta-praevia-placenta-accreta-and-vasa-praevia/
[last accessed on May 15, 2021].
Francois KE, Foley MR Antepartum and postpartum haemorrhage. In: Gabbe , Niebyl , Simpson , Landon , Galan , Jauniaux , et al
, editors. Obstetrics; Normal and Problem Pregnancies. 7th ed. Philadelphia: Elsevier Publishers; 2017. p. 395-424.
Reddy UM, Abuhamad AZ, Levine D Executive summary of a Joint Eunice Kennedy Shiver National Institute of Child Health and Human Development, Society of Maternal-Fetal Medicine, American Institute of Ultrasound in Medicine, American College of Obstetricians and Gynaecologists, American College of Radiology, Society for Pediatric Radiology and Society of Radiologist in Ultrasound Fetal Imaging Workshop. Obstet Gynecol 2014;123:1070-5.
Tyagi P, Yadav N, Gupta U Study of antepartum haemorrhage and its maternal and perinatal outcome. Int J Reprod Contracept Obstet Gynecol 2016;5:3972-7.
Maurya A, Arya S Study of antepartum haemorrhage and its maternal and perinatal outcome. Int J Sci Res 2014;4:444-51.
Pandey VP, Pandey M Study of antepartum haemorrhage and its maternal and perinatal outcome 2016. Available from: http://imsear.li.mahidol.ac.th/handle/123456789/175784
. [last accessed on May 15, 2021].
Adekanle DA, Adeyemi AS, Fadero FF Antepartum haemorrhage and pregnancy outcome in Lautech Teaching Hospital in southwest Nigeria. J Med Sci 2011;12:43-7.
Vergani P, Ornaghi S, Pozzi I, Beretta P, Russo FM, Follesa I, et al
. Placenta previa: Distance to internal os and mode of delivery. Am J Obstet Gynecol 2009;201:266.e1-5.
Tuzovic L Complete versus incomplete placenta previa and obstetric outcome. Int J Gynaecol Obstet 2006;93:110-7.
Fan D, Wu S, Liu L, Xia Q, Wang W, Guo X, et al
. Prevalence of antepartum haemorrhage in women with placenta previa: A systematic review and meta-analysis. Available from: www.nature.com/scientificreports/ [last accessed on May 18, 2020].
Pivano A A score to predict the risk of emergency caesarean delivery in women with antepartum bleeding and placenta previa. Eur J Obstet Gynecol Reprod Biol 2015;195:173-6.
Young BC, Nadel A, Kaimal A Does previa location matter? Surgical morbidity associated with location of a placenta previa. J Perinatol 2014;34:264-7.
Daskalaki G Impact of placenta previa on obstetric outcome. Int J Obstet Gynecol 2011;114:238-41.
Bhat SM, Hamdi IM, Bhat SK Placenta previa in a referral hospital in Oman. Saudi Med J 2004;25:728-31.
Nyango DD, Mutihir JT, Kigbu JH Risk factors for placenta praevia in Jos, North Central Nigeria. Niger J Med 2010;19:46-9.
Loto O, Onile TG Placenta praevia at the Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife. A ten-year analysis. Niger J Clin Pract 2008;11:130-3.
Ikechebelu JI, Onwusulu DN Placenta praevia: Review of clinical presentation and management in a Nigerian Teaching Hospital. Niger J Med 2007;16:61-4.
Ezechi CO, Kalu BK, Nwokoro CA, Njokanma FO, Loto MO, Okeke CE Placenta previa: A study of risk factors, maternal and fetal outcomes. Trop J Obstet Gynecol 2004;21:131-4.
Onebunne AC, Aimakhu CO Prevalence and pregnancy outcomes in patients with antepartum haemorrhage in a tertiary hospital in Ibadan, Nigeria. Int J Reprod Contracept Obstet Gynecol 2012;8:26-32.
Adegbola O, Okunowo AA Pattern of antepartum haemorrhage at the Lagos University Teaching Hospital Lagos, Nigeria. Nig Med Pract 2010;58:41-9.
Konar H Antepartum haemorrhage. In: Konar H, editor. DC Dutta’s Textbook of Obstetrics Including Perinatology and Contraception. 7th ed. New Delhi, India: Jaypee Brothers Medical Publishers Ltd; 2013. p. 241-59.
MacAfee CHG Placenta previa. Study of 174 cases. J Obstet Gynecol 1982;12:13-7.
Sekiguchi A, Nakai A, Kawabata I, Hayashi M, Takeshita T Type and location of placenta previa affect preterm delivery risk related to antepartum hemorrhage. Int J Med Sci 2013;10:1683-8.
Long SY, Yang Q, Chi R, Luo L, Xiong X, Chen ZQ Maternal and neonatal outcomes resulting from antepartum hemorrhage in women with placenta previa and its associated risk factors: A single-center retrospective study. Ther Clin Risk Manag 2021;17:31-8.
Hasegawa J, Higashi M, Takahashi S, Mimura T, Nakamura M, Matsuoka R, et al
. Can ultrasonography of the placenta previa predict antenatal bleeding? J Clin Ultrasound 2011;39:458-62.
Saitoh M, Ishihara K, Sekiya T, Araki T Anticipation of uterine bleeding in placenta previa based on vaginal sonographic evaluation. Gynecol Obstet Invest 2002;54:37-42.
Burodo AT, Shehu CE Placenta praevia at Usmanu Danfodiyo University Teaching Hospital, Sokoto: A 5-year review. Sahel Med J 2013;16:56-9.
Sarella L, Chinta A A study on maternal and perinatal outcome in placenta previa. Sch J App Med Sci 2014;2:1555-8.
Kurude VN, Saha D Study of maternal and perinatal outcome in placenta previa at tertiary care center. Paripex Ind J Res 2017;6:44-5.
Obiechina NJA, Eleje GU, Ezebialu IU, Okeke CAF, Mbamara SU Emergency peripartum hysterectomy in Nnewi: A 10-year review. Niger J Clin Pract 2012;15:168-71.
Chigbu CO, Iloabachie GC The burden of caesarean section refusal in a developing country setting. BJOG 2007;114:1261-5.
Ezugwu EC, Iyoke CA, Iloghalu IE, Ugwu EO, Okeke TC, Ekwuazi KE Caesarean section rate and its outcome in a tertiary hospital in Enugu, South East Nigeria. Int J Med Health Dev 2017;22:24-30.
Takai IU, Sayyadi BM, Galadanci HS Antepartum hemorrhage: A retrospective analysis from a northern Nigerian teaching hospital. Int J Appl Basic Med Res 2017;7:112-6.
Wasnik SK, Naiknaware SV Antepartum haemorrhage: Causes and its effects on mother and child: An evaluation. Obstet Gynecol Int J 2015;3:255-8.
Ezzat L, Saed A, Salah M, Khalil M Incidence of placenta previa at Aswan University Hospital one year study. Med J Cairo Univ 2015;83:841-3.
Okafor I, Ugwu EO, Obi N, Nwogu-Ikojo EE. Uterine packing in the management of complete placenta previa. Niger J Med 2014;23:321-4.
WHO. WHO recommendations for the prevention and treatment of postpartum haemorrhage. WHO Library Cataloguing-in-Publication Data 2012:1-48.
Sorakayalapeta MR, Manoli NS Maternal and perinatal outcome in placenta previa: An observational study at a tertiary care hospital in Mysore, Karnataka, India. Int J Reprod Contracept Obstet Gynaecol 2019;8:1322-6.
Ugwu GO, Iyoke CA, Ezugwu EC, Ajah LO, Onah HE, Ozumba BC A comparison of the characteristics of maternal near-misses and maternal deaths in Enugu, Southeast Nigeria: A 3-year prospective study. Int J Womens Health 2020;12:207-11.
Chukudebelu WO, Ozumba BC Maternal mortality at the University of Nigeria Teaching Hospital, Enugu: A 10-year survey. Trop J Obstet Gynaecol 1988;1:23-6.
Bhutia PC, Lertbunnaphong T, Wongwananuruk T, Boriboonhirunsarn D Prevalence of pregnancy with placenta previa in Siriraj Hospital. Siriraj Med J 2011;63:191-5.
[Table 1], [Table 2], [Table 3], [Table 4]