Journal of The Analgesics, 2013, 1, 65-72
65
Pregnancy with Low Lying Placenta in the Emergency Room
V.S. Gulecha*, M.S. Mahajan, R.A. Khandare and C.D. Upasani
S.S.D.J. College of Pharmacy, Neminagar, Chandwad (M.S.), 423 101, India
Abstract: Placenta is the tissue that nourishes the fetus in the uterus during gestation period with the attached umbilical
cord. Placenta plays an important role in the normal development of the fetus in the uterus. Its position inside the uterus
describes whether the delivery of baby will be normal (natural) or not. Low lying placenta is condition in which the
placenta moves in the lower part of the uterus and blocks the cervix partially or completely. Though the pathophysiology
of low lying placenta is not clearly known, its incident rate is 2-3% of all the births and the haemorrhage is the common
symptom. Some times intra amniotic inflammation or intra uterine inflammation are seen. Any fixed remedy is though not
available for this disorder but tocolytics generally preferred along with general anesthetics. The purpose of writing this
review is to highlight the gravity of this subject.
Keywords: Placenta previa, low lying placenta, preterm labour, transvaginal sonography.
INTRODUCTION
Low lying placenta is condition in which the placenta
moves in the lower part of the uterus and blocks the
cervix. If it partially covers the cervix it is called as
placenta previa. Thus these two terms, low lying
placenta and placenta previa mainly describes the
position of the placenta in relation to the cervix. In
some cases as it blocks the cervix completely, natural
delivery is not possible and a c-section or cesarean
delivery is preferred [1]. However, in about 90% cases,
the fetal presenting part. The placenta either totally or
partially lies within the lower uterine segment. Placenta
previa complicates approximately 0.3%- 0.5% of
pregnancies or about 4.8 per 1,000 deliveries. The risk
of recurrent placenta previa is as high as 4% to 8%
with the number of prior cesarean sections, rising to
10% with four or more. Although some distinctions in
outcome may be made among the different degrees of
true placenta previa, all are potentially associated with
life-threatening haemorrhage during labor. The degree
of placenta previa alone can neither predict the clinical
Figure 1: Low lying placenta.
it will migrate upward on its own and then there is no
concern [2]. In normal pregnancies, the placenta is
attached to the fundus i.e. to the upper part of the
uterus.
course accurately, nor can it serve as the sole guide for
management decisions [3].
In placenta previa, most probably an implantation of
the placenta in the lower uterine segment in advance of
1.
Complete placenta previa: where the placenta
completely covers the internal os;
2.
Partial placenta previa: where the placenta
partially covers the internal os. Thus, this
scenario occurs only when the internal os is
dilated to some degree;
*Address correspondence to this author at the Department of Pharmacology,
SNJB’S SSDJ College of Pharmacy, Neminagar, Chandwad, Dist: Nashik-000
000, India; Tel: +91-9860668826; E-mail: [email protected]
E-ISSN: 2311-0317/13
Placenta previa has been categorized into 4 types:
© 2013 Pharma Professional Services
66
Journal of The Analgesics, 2013, Vol. 1, No. 2
Gulecha et al.
Figure 2: Types of placenta previa.
3.
Marginal placenta previa: where placenta just
reaches the internal os, but does not cover it;
4.
Low-lying placenta: where placenta extends
into the lower uterine segment but does not
reach the internal os [4].
INCIDENCE RATE
True placenta previa persists in 1 in 200 live births
and 1 in 1,500 first-time mothers [5]. Placenta previa
occurs in 0.3-2.0% of all births. This range in the
reported incidence results from differing definitions,
methods of diagnosis and gestational ages at the time
of diagnosis. In addition, the frequency varies in
different patient populations [6].
PATHOPHYSIOLOGY
The women with prior placenta previa or multiple
prior cesarean sections are at highest risk. The strong
association between placenta previa and parity has
suggested that "endometrial damage" is an etiologic
factor. Presumably, each pregnancy "damages" the
endometrium underlying the implantation site,
rendering the area unsuitable for implantation.
Subsequent pregnancies are more likely to become
implanted in the lower uterine segment by a process of
elimination. This effect is most clearly seen with prior
term pregnancies, but multiple early pregnancy
terminations may also be related to an increased
incidence of placenta previa. There is evidence that low
implantations are much more common early in
pregnancy, but that the great majority of these
“resolves" and never become symptomatic. With the
progression of pregnancy, more than 90% of these lowlying placentas identified early in pregnancy will appear
to move away from the cervix and out of the lower
uterine segment. Although the term "placental
migration" has been used, most authorities do not
believe the placenta moves. Rather, it is felt the
placenta grows preferentially toward a bettervascularized fundus (trophotropism), whereas the
placenta overlying the less well-vascularized cervix
may undergo atrophy [7].
Subsequent growth of the placenta after low
implantation is either centripetal (resulting in central
placenta previa) or unidirectional toward the more richly
vascularized fundus. The latter mechanism is common,
as demonstrated by the finding of an eccentric,
marginal, or even velamentous insertion of the cord.
The association of velamentous cord insertions with
placenta previa and the pathologic entity of vasa previa
are both consistent with a dynamic process sometimes
called "placental migration". Unidirectional growth of
the placenta coupled with disappearance of the early
placenta at the original implantation site results in a
placenta that appears to have moved away from its
original location. The insertion point of the cord on the
membranes marks the original location of the definitive
placenta. The primary implantation site is probably low
in the great majority of cases. An alternative mechanism involving fundal implantation with unidirectional
growth toward the cervix has been suggested, but this
mechanism has been observed only rarely with serial
sonograms. Therefore, a fundal placenta in the second
trimester is reassuring evidence that a placenta previa
will not exist in the third trimester [7].
ETIOLOGY
The exact etiology of placenta previa is unknown.
The condition may be multifactorial and is postulated to
be related to multiparty, multiple gestations, advanced
maternal age, previous cesarean delivery, previous
abortion and possibly, smoking. Unlike first trimester
bleeding, second and third trimester bleeding is usually
secondary to abnormal placental implantation [8].
Pregnancy with Low Lying Placenta in the Emergency Room
Journal of The Analgesics, 2013, Vol. 1, No. 2
CAUSES
The causes of placenta previa are unknown, though
some risk factors have been identified [7,8].
Risk factor
Does it apply?
Smoking
No
6 or more births
No
Previous C-sections
No
Cocaine use
No
Multiple pregnancy
No
Previous uterine insult, including
D&Cs
Yes, but they shouldn't count.
IVF
Yes.
67
The risk to the baby is greater. The mortality rate for
previa babies seems to hover somewhere near 10%,
triple the neonatal mortality rate overall. 60% of these
deaths occur from conditions related to premature birth.
Premature delivery will occur in about two-thirds of
previa cases.
Aside from complications of prematurity, previa
babies also seem to experience a higher incidence of
growth restriction and congenital physical anomalies
[11].
CLINACAL HISTORY
OTHER CAUSES
•
Prior uterine insult or injury---
•
Risk factors
o
Prior placenta previa (4-8%)
o
First subsequent
cesarean delivery
o
Multiparity (5% in grand multiparous patients)
o
Advanced maternal age
o
Multiple gestations
o
Prior induced abortion
o
Smoking [9].
pregnancy
following
a
REGIONAL FACTOR
Significance of region is somewhat controversial.
Some studies suggest an increased risk of placenta
previa among blacks and Asians, whereas other
studies cite no difference [10].
AGE FACTOR
Women older than 30 years are 3 times more likely
to have placenta previa than women younger than 20
years. [11].
Approximately 6 days after fertilization, the
blastocyst attaches to the decidual cells of the
endometrial epithelium. The thin outer layer (i.e.,
trophoblast) rapidly proliferates and differentiates into a
cytotrophoblast and a syncytiotrophoblast. Fingerlike
processes
extend
outward
from
the
syncytiotrophoblast, through the decidual layer and into
the endometrial stroma [12]. Probably within 2 weeks of
fertilization, networks of lacunae form within the
syncytiotrophoblast. These spaces are filled with
maternal blood derived from ruptured endometrial
capillaries. This process is the beginning of
uteroplacental circulation, and these lacunar networks
eventually form the intervillous spaces of the mature
placenta. By the end of the second week, chorionic villi
begin to form. These structures form the fetal
component of the placenta and project into the
intervillous space.
Placenta previa typically occurs as a result of
abnormally low implantation. Although no specific
cause has been identified to date, this condition has
been assumed to occur as a result of abnormal
endometrial vascularization related to atrophy or
scarring from prior trauma or inflammation [13]. As the
lower uterine segment thins in late pregnancy, the
margins of the abnormally implanted placenta are
altered. Various degrees of placental detachment may
develop, with ensuing maternal hemorrhage from the
intervillous space. During labor, significant fetal
hemorrhage also may occur as a result of disrupted
villous placental vessels [14].
SYMPTOMS
EFFECTS
The danger to the mother is minimal if she's getting
proper care. The main risk is from haemorrhage, which
can generally be treated with transfusions and fluid
replacement as necessary.
The classic symptom of placenta previa is bright red
bleeding in the second or third trimester. Only about
10% of women with placenta previa reach term without
bleeding. The bleeding is generally caused by changes
in the uterus and cervix as the body prepares for
68
Journal of The Analgesics, 2013, Vol. 1, No. 2
Gulecha et al.
delivery, although it can also be provoked by
intercourse or vaginal examination [15].
The average gestational age at the start of bleeding
is 32 weeks; with complete previa the onset of bleeding
tends to be earlier. (The relationship between the onset
of bleeding and neonatal complications is inversely
proportional: The earlier the mother bleeds, the greater
the risk of premature birth.) [16]
previa is undetected by ultrasound, it often
remains undiagnosed until it manifests itself
as bright red bleeding late in the pregnancy
[18].
2)
The classic clinical presentation of placenta
previa is painless bleeding in the late second
trimester or early third trimester. However, some
patients with placenta previa will experience
painful bleeding, possibly the consequence of
uterine contractions or placental separation,
whereas others will experience no bleeding at all
before labor. Placenta previa may also lead to an
unstable lie or malpresentation in late
pregnancy. The majority of cases of placenta
previa are diagnosed during routine sonography
in asymptomatic women, usually during the
second trimester. The initial episode of bleeding
has a peak incidence at about the 34th week of
pregnancy, although one-third of cases become
symptomatic before the 30th week and one-third
after the 36th week. Absence of bleeding prior to
term does not rule out placenta previa. In
approximately 10% of cases, bleeding begins
only with the onset of labor, and in these
situations one is more likely to find a partial or
marginal placenta previa, or a low-lying placenta.
Although
transabdominal
sonography
is
frequently used for placental location, this
technique lacks some precision in diagnosing
placenta previa. Numerous studies have
demonstrated the accuracy of transvaginal
sonography for the diagnosis of placenta previa,
uniformly finding that transvaginal sonography is
superior to transabdominal sonography for this
finding. False-positive and --negative rates for
the diagnosis of placenta previa using
transabdominal sonography range from 2% to
25% [19].
3)
Transvaginal imaging technique if used properly
does not lead to increase in bleeding.This is for 2
main reasons: the vaginal probe is introduced at
an angle that places it against the anterior fornix
and anterior lip of the cervix, unlike a digital
examination, where articulation of the hand
allows introduction of the examining finger
through the cervix; and the optimal distance for
visualization of the cervix is 2-3 cm away from
the cervix, so the probe is generally not
advanced sufficiently to make contact with the
placenta. Nonetheless, the examination should
be performed by personnel experienced in
The initial bleed is usually minor and tends to stop
on its own. It is almost invariably followed by a later
bleed of greater severity. The bleeding is usually
unaccompanied by pain, although one in five women
will experience symptoms of premature labor such as
contractions [16].
SEVERE SYMPTOMS
•
contractions last about 50-80 seconds
•
contractions occur at regular intervals
•
contractions don't go away when you move
around
•
Intra amniotic or intra uterine inflammation
•
Blood from the vagina
•
Constant, severe pain -- don't wait for a whole
hour to pass
•
Membrane rupture
•
Reduced fetal movement [17].
DIAGNOSIS
1)
Low-lying placenta is often detected early in
pregnancy via Ultrasound [17].
a)
b)
Early diagnosis: - As the pregnancy
progresses, with the growth of the uterus, the
placenta is pulled safely away from the cervix
in the vast majority of these cases. This
suggests that early diagnosis is not an
especially useful tool for predicting later
complications.
Later diagnosis: - The later diagnosis of
placenta previa and the more complete the
coverage of the cervical so, the more likely it
is to persist until delivery. When a complete
placenta previa is identified after 20 weeks or
so, it is unlikely to resolve [18]. If placenta
Pregnancy with Low Lying Placenta in the Emergency Room
transvaginal sonography, and the transvaginal
probe should always be inserted carefully, with
the examiner looking at the monitor to avoid
putting the probe in the cervix. Translabial
sonography has been suggested as an
alternative to transvaginal sonography and has
been shown superior to transabdominal
sonography for placental location. However,
because transvaginal sonography is accurate,
safe and well tolerated, it should be the imaging
modality of choice [20].
MANAGEMENT
The goal of management for placenta previa is to
obtain the maximum fetal maturation possible while
minimizing the risk to both the fetus and the mother.
The basis for this approach is that episodes of bleeding
are usually self-limited and not fatal to either the fetus
or the mother in the absence of inciting trauma (e.g.,
intercourse, pelvic examination) or labor. Under
carefully controlled conditions, delivery of the fetus may
be safely delayed to a more advanced stage of maturity
in a significant proportion of cases. An additional
advantage to this approach is that a small proportion of
cases, particularly those discovered early with lesser
degrees of placenta previa, will resolve to an extent
permitting vaginal delivery at term. It is reasonable to
hospitalize women with placenta previa while they are
having an acute bleeding episode or uterine
contractions. Women who present with bleeding in the
second half of pregnancy should have a sonographic
examination for placental location prior to any attempt
to perform a digital examination. Digital examination
with a placenta previa may provoke catastrophic
hemorrhage and should not be performed [21]. It is
reasonable to hospitalize women with placenta previa
while they are having an acute bleeding episode or
uterine contractions. One to two wide-bore intravenous
cannulas should be inserted and blood taken for a full
blood count and type and screen. In the absence of
massive bleeding or other complications, coagulation
studies are not helpful [22]. The blood bank must be
capable of making available at least 4 units of
compatible packed red blood cells and coagulation
factors at short notice. Rh immune globulin should be
administered to Rh-negative women. A KleihauerBettke test for quantification of fetal-maternal
transfusion should also be performed in Rh-negative
women because the mother may require increased
doses of Rh immune globulin. Small studies have
suggested a benefit of tocolytic therapy for women with
placenta previa who are having contractions [23].
Contractions may lead to cervical effacement and
Journal of The Analgesics, 2013, Vol. 1, No. 2
69
changes in the lower uterine segment, provoking
bleeding, which in turn, stimulates contractions,
creating a vicious cycle. Steroids should be
administered in women between 24 and 34 weeks of
gestation, generally at the time of admission for
bleeding, to promote fetal lung maturation. The patient
and her family should have a neonatology consultation
so that the management of the infant after birth may be
discussed. In women who have a history of cesarean
delivery or uterine surgery, detailed sonography should
be performed to exclude placenta accreta [24]. Before
32 weeks of gestation, moderate-to-severe bleeding
when there is no maternal or fetal compromise may be
managed aggressively with blood transfusions, rather
than resorting to delivery. When the patient has had no
further bleeding for 48 hours, she may be considered
for discharge as long as there are appropriate home
conditions to allow outpatient management. Women
who are stable and asymptomatic, and who are reliable
and have quick access to hospital, may be considered
for outpatient management [25].
TIMING OF DELIVERY AND MODE OF DELIVERY
As gestational age advances, there is an increased
risk of significant bleeding, necessitating delivery. It is
preferable to perform a cesarean delivery for placenta
previa under controlled scheduled conditions rather
than as an emergency. In a stable patient, it is
reasonable to perform a cesarean delivery at 36-37
weeks of gestation, after documentation of fetal lung
maturity by amniocentesis. If the amniocentesis does
not demonstrate lung maturity and patient is stable it is
reasonable to wait till 38 or 39 weeks of pregnancy or
earlier if bleeding occurs or patient goes into labor.
There is consensus that a placenta previa, which totally
or partially overlies the internal cervical os, requires
delivery by cesarean. However, the mode of delivery
when the placenta lies in proximity to the internal os is
more controversial. Women with a placenta -- internal
os distance of less than 2 cm who undergo a trial of
labor almost invariably experience significant bleeding
during labor, necessitating cesarean delivery and many
centers recommend cesarean delivery in these cases.
Women whose placentas are 2 cm or more away from
the os can undergo a normal labor. It is important to
realize that, in women with a placenta that extends into
the non-contractile lower uterine segment who have a
vaginal delivery, there is potential for postpartum
hemorrhage [26].
Anesthesia for Delivery
In the past, it was generally recommended that
cesarean deliveries for placenta previa be performed
70
Journal of The Analgesics, 2013, Vol. 1, No. 2
under general anesthesia. It was believed that this
allowed more controlled surgery. Many studies have
found these are associated with significantly greater
estimated blood loss and greater requirements for
blood transfusion than those performed under regional
anesthesia, possibly due to increased uterine
relaxation associated with general anesthetic. Many
institutions generally perform cesarean deliveries for
placenta previa under regional anesthesia [27].
TREATMENT
Gulecha et al.
•
If the pregnancy is close to term, and
amniocentesis shows that the baby's lungs have
sufficiently matured, a C-section may be
performed. The baby will probably be fine.
•
If the pregnancy is not close to term, but the
mother and/or baby are in significant distress, a
C-section may be performed. The baby might not
be fine [31].
Treating Pain During Labor:
•
Intravenous or intramuscular analgesic Using an IV, a doctor will administer pain
medicine to go directly into your blood and help
ease pain. Analgesics do not get rid of all the
pain but help make pain bearable. After receiving
an IV or intravenous analgesic, you still have the
option of requesting an epidural or spinal
anethesia later [31].
•
Epidural anesthesia - During an epidural, a
doctor injects medicine into the lower part of the
spine. The medicine blocks pain in the parts of
the body below the shot, including the pain of
contractions. Epidurals allow most women to be
awake and alert with very little pain [31].
•
If there's bleeding, on its first occurrence mother
and baby will be evaluated. Upon cessation of
bleeding, if their condition is stable, and if the mother
can be counted on to be psychotically compliant, and if
she lives close enough to a hospital to crawl there on
her own in the dead of a midwinter night, tangled in her
blood-soaked sweatpants and Steely Dan T-shirt, bed
rest at home may be prescribed [30].
Pudendal Block- During a pedendal block,
numbing medicine is injected into the vagina and
a nearby nerve called the pudendal nerve for
pain relief with alertness. Pudendal blocks are
only used late in labor, usually right before the
baby's head comes out [31].
•
Spinal anesthesia - Spinal anesthesia uses
numbing medicines to numbs the entire body
below an injection point in your spine to give
immediate relief. Spinal anesthesia is most
frequently used during emergency C-sections.
Upon Subsequent and More Serious Bleeding
Episodes:
MEDICATION
There is no treatment that can move the placenta
out of troubles way. Patients are treated expectantly,
with volume replacement, transfusions, tocolytics, and
emergent cesarean delivery when necessary. Without
endangering the life of the mother, all attempts are
made to delay delivery until the fetal lungs mature [28].
In the absence of bleeding, expectant management
is indicated. Patients may be advised to restrict their
activities, eliminating exercise, lifting, strenuous
movements, and especially sexual intercourse. Pelvic
and rectal examinations are strictly contraindicated.
Because careless noodling could easily nick the
placenta, nothing should be introduced into the vagina.
If the patient remains asymptomatic, a scheduled Csection is performed once amniocentesis has
established adequate fetal lung maturity [29].
•
If the baby shows no signs of distress and the
pregnancy is significantly pre-term, the mother
may be given blood transfusions and medication
to prevent premature labor. She may also be
treated with steroids to hasten the maturation of
the baby's lungs. Hospitalization until delivery is
generally required. (Medical personnel are
advised to be aware of the likelihood of a
recurrence of the earlier freak-the-fuck-right-out,
as later flare-ups are invariably more severe.)
[30]
No medication is of specific benefit to a patient with
placenta previa. Tocolytics may be cautiously
considered in some circumstances. Encourage patients
with known placenta previa to maintain intake of iron
and folate as a safety margin in the event of bleeding.
Tocolytics
Prevent pre-term labor or contractions [2,4].
Magnesium Sulfate
Nutritional
supplement
in
hyperalimentation;
cofactor in enzyme systems involved in neurochemical
Pregnancy with Low Lying Placenta in the Emergency Room
transmission and muscular excitability. In adults, 60180 mEq of potassium, 10-30 mEq of magnesium, and
10-40 mEq of phosphate per day may be necessary for
optimum metabolic response. Administer IV or IM for
seizure prophylaxis in preeclampsia. Use IV route for
quicker onset of action in true eclampsia. Discontinue
treatment as soon as desired effect is obtained. Repeat
doses dependent on continuing presence of patellar
reflex and adequate respiratory function [4].
DOSING
Adult
Loading dose: 6 g IV over 20 min; then 2-4 g/h
continuous infusion; adjust to lessen contractions; not
to exceed 4 g/h [4].
Pediatric
Administer as in adults; alternatively, 20-100 mg/kg/
dose IV q4-6h prn; in severe cases, may use doses as
high as 200 mg/kg/dose; not to exceed 4 g/h. [4]
INTERACTION
Concurrent use with Nifedipine may cause
hypotension and neuromuscular blockade; may
increase
neuromuscular
blockade
seen
with
aminoglycosides
and
potentiate
neuromuscular
blockade produced by tubocurarine, vecuronium, and
succinylcholine; may increase CNS effects and toxicity
of CNS depressants and betamethasone; may increase
cardiotoxicity of ritodrine [4].
CONTRA INDICATION
Documented hypersensitivity; heart block; Addison
disease; myocardial damage; myasthenia gravis;
impaired renal function; severe hepatitis. [4]
PRECAUTION
Fetal monitoring is essential, may decrease fetal
heart rate; maternal magnesium toxicity may occur at
low or high rates of infusion; magnesium may alter
cardiac conduction, leading to heart block in patients
who are digitalized; monitor respiratory rate, deep
tendon reflex, and renal function when electrolytes are
administered parenterally; caution when administering
magnesium because may produce significant
hypertension or asystole; in overdose, calcium
gluconate (10-20 mL IV of 10% solution) can be
administered as an antidote for clinically significant
hypermagnesemia [32].
Journal of The Analgesics, 2013, Vol. 1, No. 2
71
SURGICAL CARE
The distance between the placental edge and
internal cervical os on transvaginal ultrasonography
after 35 weeks’ gestation is valuable in planning route
of delivery. When the placental edge is greater than 2
cm from the internal cervical os, women can be offered
a trial of labour with a high expectation of success.
However, a distance of less than 2 cm from the os is
associated with a higher cesarean rate, although
vaginal delivery is still possible depending on the
clinical circumstances. The timing of delivery is often
driven by the patient’s history and an increased risk for
bleeding with advancing gestation. Most authorities
recommend delivery at 36-37 weeks' gestation after
confirming fetal lung maturity via amniocentesis.
However, if the fetal lung maturity testing is immature
or is not available, then delivery is often scheduled for
38 weeks' gestation. Most often a low transverse
uterine incision is used; on the other hand, a vertical
uterine incision may be considered secondary to an
anterior placenta and risk of fetal bleeding. If the
patient is at increased risk for invasive placentation
(accreta, increta, or percreta), then the patient and
surgical team must be prepared prior to delivery. These
invasive placentations carry a high mortality rate (7%
with placenta accreta) as well as a high morbidity rate
(blood transfusion, infection, adjacent organ damage).
These complicated pregnancies must have delivery
plans that include patient-matched blood and informed
consent
for
possible
cesarean
hysterectomy.
Predelivery placement of balloon catheters for
angiographic embolization of pelvic vessels is a
technique described in reducing blood loss associated
with cesarean hysterectomy. Other means to control
hemorrhage include B-Lynch or parallel vertical
compression
sutures,
uterine
artery
ligation,
hypogastric artery ligation, as well as, hysterectomy. In
the case of a small and focal placenta accreta,
resection of the implantation site and primary repair
may allow for uterine preservation [33].
CONCLUSION
It can be concluded from the information furnished
above that in placenta previa or lower lying (line)
placenta, placenta is attached to lower side of uterus
that create problem in delivery. In about 90% of all
cases placenta itself moves up side of uterus leading to
the normal delivery. Though its incident rate is 0.2-3%
of all births, attention must be given toward this rare
disorder as it leads to severe complications later at the
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Journal of The Analgesics, 2013, Vol. 1, No. 2
Gulecha et al.
time of delivery. No clear diagnosis has been yet set or
discovered to diagnose this emergency condition, only
late diagnosis is more applicable. Patient education
also plays important role in the counseling of disorder,
a proper medical attention must be provided along with
treatment.
[19]
Gilliam M, Rosenberg D, Davis F. The likelihood of placenta
previa with greater number of cesarean deliveries and higher
parity. Obstet Gynecol 2002; 99(6): 976-80.
http://dx.doi.org/10.1016/S0029-7844(02)02002-1
[20]
Harma M, Gungen N, Ozturk A. B-Lynch uterine compression
suture for postpartum haemorrhage due to placenta previa
accreta. Aust N Z J Obstet Gynaecol 2005; 45(1): 93-5.
http://dx.doi.org/10.1111/j.1479-828X.2005.00340.x
[21]
Hwu YM, Chen CP, Chen HS, Su TH. Parallel vertical
compression sutures: a technique to control bleeding from
placenta previa or accreta during caesarean section. BJOG
2005; 112(10): 1420-3.
http://dx.doi.org/10.1111/j.1471-0528.2005.00666.x
[22]
Laughon SK, Wolfe HM, Visco AG. Prior cesarean and the
risk for placenta previa on second-trimester ultrasonography.
Obstet Gynecol 2005; 105(5 Pt 1): 962-5.
[23]
Miller DA, Chollet JA, Goodwin TM. Clinical risk factors for
placenta previa-placenta accreta. Am J Obstet Gynecol
1997; 177(1): 210-4.
http://dx.doi.org/10.1016/S0002-9378(97)70463-0
[24]
Mustafa SA, Brizot ML, Carvalho MH, et al. Transvaginal
ultrasonography in predicting placenta previa at delivery: a
longitudinal study. Ultrasound Obstet Gynecol 2002; 20(4):
356-9.
http://dx.doi.org/10.1046/j.1469-0705.2002.00814.x
[25]
Oppenheimer L, Society of Obstetricians and Gynaecologists
of Canada. Diagnosis and management of placenta previa. J
Obstet Gynaecol Can 2007; 29(3): 261-73.
[26]
Ornan D, White R, Pollak J, Tal M. Pelvic embolization for
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904-10.
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Received on 22-11-2013
Accepted on 26-11-2013
Published on 31-12-2013
DOI: http://dx.doi.org/10.14205/2311-0317.2013.01.02.5
© 2013 Gulecha et al.; Licensee Pharma Professional Services.
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