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Placenta previa SlideShare

25. Complication of Placenta Previa Maternal complication 1- Abnormal presentation and position. 2- Premature labor. 3- Prolonged labor. 4- More chance of surgical intervention. 5- Placenta may be adherent: Placenta accreta, increta, or percreta 6- Postpartum hemorrhage 7- Maternal shock and maternal death. 26 Placenta Previa- Symptoms, Causes & Treatment. 1. Placenta Previa Symptoms, Causes & Treatment. 2. A condition where the placenta lies low in the uterus and partially or completely covers the cervix. The placenta may separate from the uterine wall as the cervix begins to dilate (open) during labor. 3 Management of preterm labour in Placenta previa and Abruptio placentae NAVEENA.R.L. 09 Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. If you continue browsing the site, you agree to the use of cookies on this website Placenta Previa:Placental Abruption 1. PLACENTA PREVIA/ PLACENTAL ABRUPTION Allison Krickl Edgewood College School of Nursing 2. DEFINITIONS v Placenta previa- an abnormal implantation of the placenta in the lower segment of the uterus near or over the cervical os instead of attaching to the fundus

Placenta previa

Slideshow search results for placenta previa Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. If you continue browsing the site, you agree to the use of cookies on this website Placenta previa 1. PLACENTA PREVIA PESS. MANZO VELASQUEZ ALONDRA GPE. PESS. VEGA CRUZ GLADYS AGLAE 2. La implantación de la placenta en condiciones normales, tiene lugar en el fondo del útero, ya sea en la pared anterior o posterior. La placenta previa es una placenta implantada en el segmento inferior del útero que se ubica por delante del polo de presentación del feto concepto, incidencia, etiología, diagnostico y tx de placenta previa. Utilizamos tu perfil de LinkedIn y tus datos de actividad para personalizar los anuncios y mostrarte publicidad más relevante

PLACENTA 1. 1 PLACENTA • This is a fetomaternal organ. • It has two components: - Fetal part - develops from the chorionic sac ( chorion frondosum ) - Maternal part - derived from the endometrium ( functional layer - decidua basalis ) • The placenta and the umbilical cord are a transport system for substances between the mother and the fetus.( vessels in umbilical cord. Placenta previa is more common in women of advanced maternal age (over 35) and in patients with multiparity; it occurs in 1 in 1500 deliveries of 19-year old, and 1 in 100 deliveries of women over 35. The incidence of placenta previa has increased over the past 30 years; this increase is attributed to the shift in older women having infants Morphometric and Immunohistochemical Examination of Changes in Umbilical Cord Structure of Placenta Previa and Normotensive Patients. Upcoming SlideShare. Loading in 5. ×. 1 La placenta previa es el hechoanatómico de que la placenta estainsertada en la parte baja delútero, lejos de su lugar habitualen el fondo del mismo.La placenta previa esconsecuencia de una anomalía enel momento de la nidación ovular.Se trata de una nidaciónectópica, bien queintrauterina, del huevo, porencima del orificio interno delcuello. 6 Placenta previa. 1. PLACENTA PREVIA. 2. DEFINICIÓN Implantación anómala de la placenta en el segmento uterino inferior, sobre o muy próxima al OCI. 3. EPIDEMIOLOGÍA 0.2 - 0.5% de todos los embarazos 15 - 20 % de hemorragias de la segunda mitad del embarazo 3.3 % de muertes maternas por hemorragia obstétrica Recidiva 4 - 8 %. 4

Placenta Previa- Symptoms, Causes & Treatment - SlideShar

Placenta Previa - Placenta Previa Dr .M Movahedi Assistant professor of Ob& Gyn of IUMS Definition The presence of placental tissue overlying or proximate to the cervical os . | PowerPoint PPT presentation | free to view. PLACENTA PREVIA - Partial placenta previa:the margin of the placenta extends across but. ginecologÍa con clÍnica placenta previa alumna: marisela gaxiola villa maestro: dr. luis alberto gonzÁlez garcÍa grupo ix- Placenta praevia is where the placenta is fully or partially attached to the lower uterine segment.It is an important cause of antepartum haemorrhage - vaginal bleeding from week 24 of gestation until delivery. In this article, we shall look at the pathophysiology, clinical features and management of placenta praevia

Graciane P. Leal 76378-1 Maria de Fátima Sakamoto 76618-6 Hellen Deandre Nascimento 76810-3 Flávia da Cruz Oliveira 76812-0 Telma Santos Silva 76823-5 Elisabe Placenta previa. 1. PLACENTA PREVIA. EM IV CLAUDIA MARÍA RODRÍGUEZ GARZA. 2. Situación donde la placenta se inserta parcialmente o en su totalidad en el segmento inferior del útero y cubre o esta próxima al orificio cervical interno (OCI). DEFINICIÓN 27/02/2015PLACENTA PREVIA. 3 Slideshow search results for placenta Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. If you continue browsing the site, you agree to the use of cookies on this website Placenta previa 1. ROSA ELENA GRACIA GARCÍA 2. TOTAL: el orificio cervicouterino interno esta cubierto por completo por la placenta PARCIAL: placenta cubre parcialmente el orificio interno MARGINAL: el borde de la placenta esta en el margen del orificio interno IMPLANTACIÓN BAJA: la placenta esta implantada en el segmento uterino inferior Localizada sobre el orificio interno o muy cerca de este

management of placenta previa - SlideShar

Placenta Previa:Placental Abruption - slideshare

Placenta Previa This program is designed for the second semester student caring for a non stable Obstetrical patient with placenta previa. Incorporated are the skills and medications necessary for caring for the obstetrical patient and the recognition of the possible implications of placenta previa. Objectives: 1 Writing is a complex skill for every student. Actually, they need it to be in order to successfully go through college. Not only students are intimate to the writing skills a lot of Placenta Previa Case Study Slideshare people are also eager to write a good article. In the academic years of the student, [ In women with low-lying placenta or placenta previa, a repeat ultrasound should be done ≥32 weeks to reassess placental location; if the placental edge is >20 mm (normal placental location) or there is an overlap of >20 mm (definitive placenta previa), no further assessment is necessary.6, 25, 32, 33, 35 In cases with the placental edge <20. trabalho de placenta previa O SlideShare utiliza cookies para otimizar a funcionalidade e o desempenho do site, assim como para apresentar publicidade mais relevante aos nossos usuários. Se você continuar a navegar o site, você aceita o uso de cookies

Placenta Previa - Free download as Powerpoint Presentation (.ppt), PDF File (.pdf), Text File (.txt) or view presentation slides online. Scribd is the world's largest social reading and publishing site riesgo de presentar placenta previa.2 Con la incidencia en aumento de las cesáreas combinado con el aumento de la edad materna, el número de casos de placenta previa y sus com-plicaciones continuarán incrementándose.5 Desde una perspectiva de salud pública, la asociación entre placenta previa y cesárea anterior es preo-cupante Placenta previa is a condition in which the placenta is attached close to or covering the cervix (opening of the uterus). Placenta previa occurs in about one in every 200 live births. There are three types of placenta previa: Total placenta previa. The placenta completely covers the cervix. Partial placenta previa

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  1. Placenta previa means the placenta has implanted at the bottom of the uterus, covering the cervix. When a baby is ready to be born, the cervix (neck of the womb) dilates (opens) to allow the baby to move out of the uterus and into the vagina. When a woman has placenta previa (the placenta has implanted at the bottom of the uterus, over the.
  2. La placenta previa consiste en que la placenta obstruye total o parcialmente el orificio del cuello del útero. Descubre cuáles son sus causas y síntomas
  3. al. El tratamiento consiste en actividad.
  4. a previa porque antecede a la presentación a partir de la semana 20 de gestación
  5. 3. INCIDENCIA Placenta previa está relacionada directamente con el número de cesáreas 0.67% Luego de la primera cesárea 1.8% Luego de la segunda cesárea 3% Luego de la tercera cesárea 10% Luego de la cuarta cesárea Una vez localizada la placenta previa, la posibilidad de acretismo placentario es: 23% con antecedentes de una cesárea 35%.
  6. 2. Diagnosis of placenta previa or low-lying placenta should not be made <18 to 20 weeks gestation, and the provisional diagnosis must be confirmed after >32 weeks gestation, or earlier if the clinical situation warrants. In women with a low-lying placenta, a recent ultrasound (within 7 to 14 days) should be used to confirm placental location.
  7. I. Placenta Previa Asintomática Manejo Ambulatorio. - Incapacidad Médica, Laboral y Sexual. - Reposo en cama. - Regularizar evacuación intestinal utilizando ablandadores de heces. - Indicaciones e Instrucciones sobre síntomas de alarma. - Si la Placenta Previa, es: Oclusiva (total o parcial): Cesárea electiva a las 37 semanas

Placenta Previa - SlideShar

  1. Definition. Placenta previa is a condition wherein the placenta of a pregnant woman is implanted abnormally in the uterus. It accounts for the most incidents of bleeding in the third trimester of pregnancy.; Pathophysiology. The placenta implants on the lower part of the uterus. The lower uterine segment separates from the upper segment as the cervix starts to dilate
  2. a previa porque antecede a la presentación a partir de la semana 20 de gestación. Placenta previa (PP) es aquella que se implanta y desarrolla en el segmento inferior del útero, ocluyendo a veces el orificio cervical interno (OCI). 3. Clasificación
  3. Placenta previa is a pregnancy problem in which the placenta blocks the cervix. The placenta is a round, flat organ that forms on the inside wall of the uterus soon after conception. During pregnancy, it gives the baby food and oxygen from the mother. In a normal pregnancy, the placenta is attached high up in the uterus, away from the cervix
  4. This information is for you if you have placenta praevia (a low-lying placenta after 20 weeks of pregnancy) and/or placenta accreta (where the placenta is stuck to the muscle of your womb). It also includes information on vasa praevia. It may also be helpful if you are a partner, relative or friend of someone in this situation
  5. Placenta Previa is the development of placenta in the lower uterine segment partially or completely covering the internal cervical os. Placenta Previa causes bleeding. Due to large amounts of blood lost, the heart tries to pump faster in order to compensate for blood loss. As a result, the heart pumps faster with lesser blood pumped. Assessmen
  6. Clase De Ginecología Y Obstetricia - Placenta Previa - 2015-
  7. Placenta previa. Es un problema del embarazo en el cual la placenta crece en la parte más baja de la matriz (útero) y cubre toda la abertura hacia el cuello uterino o una parte de esta. La placenta crece durante el embarazo y alimenta al feto. El cuello uterino es la abertura hacia la vía del parto

PLACENTA - SlideShar

PLACENTA PREVIA.ppt - Google Slide

Morphometric and Immunohistochemical - slideshare

  1. La placenta previa es una complicación del embarazo en la que la placenta se implanta o se desplaza de manera total o parcial en la porción inferior de útero, de tal manera que puede ocluir el cuello uterino. [1] Por lo general, suele ocurrir durante el segundo o tercer trimestre, aunque puede también suceder en la última parte del primer trimestre
  2. Vasa previa is an incredibly rare, but severe, complication of pregnancy. In vasa previa, some of the fetal umbilical cord blood vessels run across or very close to the internal opening of the cervix
  3. definition- PLACENTA PREVIA-abnormal implantation of the placenta in the lower uterine segment near or over the internal cervical os. TYPES-1)Complete-os entirely covered. 2)partial-only part of os covered. 3)marginal-margin overlaps os. ETIOLOGY-Unknown

PPT - PLACENTA PREVIA PowerPoint presentation free to

Placenta praevia

Placenta Praevia - Causes - Clinical Features - Management

Cases of placenta previa vary and treatment depends on how far along the women is: Placenta previa can be seen on the 20 week ultrasound. Sometimes if the placenta is found to be low lying (partially or marginal) the placenta will move upward away from the cervix as the uterus grows throughout the rest of the pregnancy Definition. 1. velamentous insertion. 2. succenturiate lobe. Term. abnormal adherence of all or part of the plaacenta with partial or complete absence of the decidua basalis. Definition. placenta accreta. Term. the further extension of the placenta through the myometrium Placenta previa, or low-lying placenta, occurs when the placenta covers part or all of the cervix during the last months of pregnancy. This condition can cause severe bleeding before or during labor Introduction: Vasa previa is an uncommon obstetrical complication that poses a high risk of fetal demise if not recognized before rupture of membranes. It is vital that providers recognize risk factors for vasa previa and diagnose this condition before the onset of labor so that fetal shock or demise is prevented. Methods: We report a patient with a bilobed placenta and perinatal hemorrhage.

Vasa previa has been defined as the presence of a fetal vessel or vessels unsupported by either placenta or umbilical cord running in the membranes below the presenting fetal part, either over the cervix 1,2 or in the lower (unquantified) uterus. 3-7 In reviewing the literature in 1999, Oyelese 5 found an overall incidence of 1 in 2,500 births in four major English language series, totaling. Vasa praevia is a condition in which fetal blood vessels cross or run near the internal opening of the uterus.These vessels are at risk of rupture when the supporting membranes rupture, as they are unsupported by the umbilical cord or placental tissue.. Risk factors include low-lying placenta, in vitro fertilization. Vasa praevia occurs in about 0.6 per 1000 pregnancies Vasa Previa. In vasa previa, membranes that contain blood vessels connecting the umbilical cord and placenta lie across or near the opening of the cervix—the entrance to the birth canal. Vasa previa may cause massive bleeding in the fetus and mother when the membranes around the fetus rupture, usually just before labor starts Posterior placenta previa lying within 1 cm from the internal cervical os and total placenta previa do not migrate during the third trimester. On the other hand, other types of placenta previa may migrate but not beyond 36 weeks' gestation. The mode of delivery does not depend only on the placental

Placenta accreta, an abnormally deep attachment of the placenta into the endometrium and myometrium (the middle layer of the uterine wall), complicates 3% of primary, 11% of secondary, 40% of tertiary, 61% of quaternary, and 67% of higher-order cesarean sections for placenta previa. Partial placenta previa:the margin of the placenta extends across but Blood transfusion is given as necessary. Amniocentesis for fetal lung maturity testing - A free PowerPoint PPT presentation (displayed as a Flash slide show) on PowerShow.com - id: 16174f-ZDc1 The placenta provides oxygen and nutrients to the growing baby and removes waste products from the baby's blood. It attaches to the wall of the uterus, and the baby's umbilical cord arises from it. In most pregnancies, the placenta attaches at the top or side of the uterus. In placenta previa, the placenta attaches to the lower area of the uterus Placenta previa slideshare. · placenta previa 1. Placenta previaplacenta previa dr.M movahedi assistant professor of ob& gyn of iums 2. Definitiondefinition. Placenta praevia wikipedia. Himy wife 20 weeks so far & she had done scan then doctor said her placenta is low, doctor said 90% chance is there to come up 10% will be no chance, then doctor La placenta previa y el desprendimiento prematuro de placenta son las complicaciones más comunes de este órgano, imprescindible para la vida intrauterina del bebé. Por eso es tan importante prevenir y controlar estas enfermedades del embarazo, que pueden desembocar en un parto prematuro. Qué es la placenta previa

Vasa previaPlacenta

Placenta previa y desprendimiento de placenta - SlideShar

Antepartum haemorrhage (APH) is defined as bleeding from or in to the genital tract, occurring from 24+0 weeks of pregnancy and prior to the birth of the baby. APH complicates 3-5% of pregnancies; and is a leading cause of perinatal and maternal mortality worldwide. The causes of APH include: placenta praevia, placental abruption and local causes (such as bleeding from the vulva, vagina or. Placenta previa is the attachment of the placenta to the wall of the uterus in a location that completely or partially covers the uterine outlet (opening of the cervix).; Bleeding after the 20th week of gestation is the main symptom of placenta previa. An ultrasound examination is used to establish the diagnosis of placenta previa.; Treatment of placenta previa involves bed rest and limitation. Placenta Previa Type 3. This is a relatively severe condition of placenta previa. In this case, the placenta covers a wider portion of the cervix opening. This, as a result, creates discomfort for the mother and the baby both. It is a considerably major stage of the placenta previa and often results in C-section delivery. It is a worrying stage. 2018 Guideline on management of Placenta Praevia by RCOG. Royal College of Obstetricians and Gynaecologists have come out with its latest 2018 Guidelines on diagnosis and management of Placenta Praevia and Placenta Accreta. This is the fourth edition of this guideline the first one was published in 2001 and it is an update on 2011 guideline

The placenta is an organ that develops during pregnancy and is a lifeline for the baby. The placenta is what attaches to the umbilical cord and provides vital nutrients to the developing fetus. When the placenta does not function as it should or is damaged, it is called placental insufficiency. It may also be referred to as placental. The separation of the placenta from its site of implantation dystocia. Complication. DIC. Hypovolemic shock. Amnionic fluid embolism. Acute renal failure - A free PowerPoint PPT presentation (displayed as a Flash slide show) on PowerShow.com - id: ff822-Y2Zm Placenta previa. complicacin obsttrica consistente en la implantacin anormal de placentaria, la cual ocurre a nivel del segmento uterino y que, en ocasiones cubre parcial o totalmente el orificio cervical interno, de tal modo que obstruye el paso del feto durante el part Placenta previa is present when the leading edge is less than 2 cm from the internal os. Placenta previa usually resolves by term due to placental migration, i.e. as the uterus grows, the placenta moves away from the cervical os. Premature labour and delivery is the primary complication

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  1. La placenta previa ocurre cuando la placenta del bebé obstruye de manera total o parcial el cuello uterino de la madre (la salida del útero). La placenta previa puede provocar un sangrado grave durante el embarazo y el parto. Si tienes placenta previa, es posible que tengas sangrado durante todo el embarazo y durante el parto
  2. Global Sheep Placenta Extract Industry: Market Trends & Forecast 2015 - The Global Sheep Placenta Extract Industry 2015 Deep Market Research Report is a professional and in-depth study on the current state of the Sheep Placenta Extract industry. The report provides a basic overview of the industry including definitions, classifications, applications and industry chain structure
  3. Placenta accreta is a rare (between 1 in 300 and 1 in 2000) complication of pregnancy. This is when . the placenta grows into the muscle of the uterus, making delivery of the placenta at the time of birth very difficult. Placenta accreta is more common in women with placenta praevia who have previously had one or mor
  4. With our custom essay Placenta Previa Case Study Slideshare offer, you can Placenta Previa Case Study Slideshare be sure to get any type of essay help you are looking for. At 6DollarEssay.com, just tell us what you are looking for and our representative will provide you with the optimum and utmost dependable service you could have asked for

hemochorial placenta - type of placenta in which the chorion is the only barrier between maternal and fetal blood inner cell mass - (also known as the embryoblast) the cluster of cells in the blastocyst that will give rise to the epiblast and hypoblast (see Chapter 2), located at the embryonic pole of the blastocoe Abnormalities of Placenta and Cord. PLACENTA SUCCENTURIATA: One (usual) or more small lobes of placenta, size of cotyledon, may be placed at varying distances from the placental margin. In absence of communicating blood vessels, it is called placenta spuria. Incidence: 3%

Placenta Previa - In this placenatal abnormality, the placenta overlies internal os of uterus, essentially covering the birth canal. This condition occurs in approximately 1 in 200 to 250 pregnancies. In the third trimester and at term, abnormal bleeding can require cesarian delivery and can also lead to Abruptio Placenta. Ultrasoun Placenta praevia (PP) is defined as the placenta overlying the cervical os. It can be complete, partial, marginal, or low-lying. Partial, marginal, and low-lying PP may resolve as pregnancy progresses. In women with a scarred uterus (most commonly from a prior caesarean section), PP may be associated with an abnormally adherent placenta, where. The search strategy was developed by a medical information specialist using the indexing terms vasa previa, placenta previa, low lying placenta, succenturiate lobe or placenta, bilobate placenta, bilobed placenta, and velamentous insertion (Supplemental Data 1). The search included studies published. Preeclampsia is a condition marked by high blood pressure in pregnant women. Learn more about the causes, risk factors, symptoms, and treatment of this serious condition Índice1 Resumen2 Introducción3 Placenta previa3.1 Placenta previa de inserción baja3.2 Placenta previa marginal3.3 Placenta previa parcial3.4 Placenta previa total3.5 Causas de placenta previa3.5.1 Causas ovulares3.5.2 Causas maternas3.6 Manifestaciones clínicas4 Diagnóstico, pronóstico y tratamiento de la placenta previa5 Cuidados de Enfermería6 Objetivos7 Material y método8.

Functions of Placenta (With Diagram) In this article we will discuss about the functions of placenta. i. Respiratory: Since fetus is not exposed to the outside atmosphere, the fetal lung will be in solid state. The oxygen requirement by the developing fetus and removal of carbon dioxide from the fetal body should be taken care off by the. The incidence of placenta previa has increased over the past 30 years; this increase is attributed to the shift in older women having infants. Overall incidence is 1 in 200 deliveries; risk for recurrence may be as high as 10% to 15%. The maternal mortality rate from previas is 0.3%. Ethnicity and race have no established effects on the risk. World's Best PowerPoint Templates - CrystalGraphics offers more PowerPoint templates than anyone else in the world, with over 4 million to choose from. Winner of the Standing Ovation Award for Best PowerPoint Templates from Presentations Magazine. They'll give your presentations a professional, memorable appearance - the kind of sophisticated look that today's audiences expect

Placenta Previa Clinical Presentation: History, Physical

Placental grading

La placenta previa puede causar sangrado intenso en la madre antes del parto o durante el parto. Una cesárea podría ser necesaria. Durante el embarazo, los posibles problemas de placenta incluyen desprendimiento placentario, placenta previa y placenta adherida. Estos trastornos pueden causar un posible sangrado vaginal abundante Placental abruption is the early separation of a placenta from the lining of the uterus before completion of the second stage of labor. It is one of the causes of bleeding during the second half of pregnancy. Placental abruption is a relatively rare but serious complication of pregnancy and placed the well-being of both mother and fetus at risk. Placental abruption is also called abruptio. placenta previa aumentada de manera significativa en mujeres multíparas en comparación con la de mujeres con paridad más baja. Cesárea previa: aumenta la probabilidad de placenta previa; el riesgo se incrementa a medida que aumenta el número de cesáreas. Así mismo, los legrados también estarían implicados en la génesis de placenta previa

Placenta Praevia and Placenta Accreta: Diagnosis and Management (Green-top Guideline No. 27a) This guideline describes the diagnostic modalities and reviews the evidence-based approach to the clinical management of pregnancies complicated by placenta praevia and placenta accreta. Published 27/09/201 Pathogenesis. The 2 main causes of vasa previa are velamentous insertions (where the cord inserts directly into the membranes, leaving unprotected vessels running to the placenta) (25-62%) and vessels crossing between lobes of the placenta such as in succenturiate or bilobate placentas (33-75%) (36, 56).Less commonly, a vessel that courses over the edge of a marginal placenta or a placenta. [slideshare.net] In the third trimester it can indicate a separation of the placenta from the uterus (placental abruption) or a Placenta previa describes the situation in which the placenta attaches to the uterus close to the opening of the cervix and may cause painless vaginal bleeding Low-Lying Placenta (Placenta Previa) Medically reviewed by Debra Sullivan, Ph.D., MSN, R.N., CNE, COI Placenta previa is when the placenta covers part or all of the cervix during the last months.

It is widely believed that during the relatively short duration of a normal pregnancy the placenta progressively ages and is, at term, on the verge of a decline into morphological and physiological senescence.1-3 This belief is based on the apparent convergence of clinical, structural, and functional data, all of which have been taken, rather uncritically, as supporting this concept of the. placenta previa - placenta overlies internal os of uterus, abnormal bleeding, may require cesarian delivery. placental thickness - is measured at its mid-portion from the chorionic plate to the basilar plate, on a longitudinal plane (less than 4 cm at term). Excludes any abnormalities (fibroids, myometrial contractions, or venous lakes) Previa 21. A quick review of the patient's prenatal course, such as a known history of placenta previa, may help lead to the correct diagnosis. (medscape.com)Before a pelvic examination can be safely performed, an ultrasonographic examination should be performed to exclude placenta previa. (medscape.com)[ 17 ] If placenta previa is present, a pelvic examination, either with a speculum or with. 1. Placenta completely separated, but retained. There are three. prolonged and exhaustive labour. • Closure of the cervix preventing the placenta from being expelled. • A constriction ring in the uterus can hold up the placenta. This. separated and unnecessary kneading or fiddling of the uterus. f2

New trends in the treatment of placenta accreta

The placenta is a disc-shaped organ which provides the sole physical link between mother and fetus. During pregnancy, the placenta grows to provide an ever-larger surface area for materno-fetal exchange. At term, the placenta weighs almost 500 g, has a diameter of 15-20 cm, a thickness of 2-3 cm, and a surface area of almost 15 m 2. POTENTIAL FOR PLACENTA PREVIA AT TERM BY GESTATIONAL AGE AT DIAGNOSIS. If a placenta previa or low-lying placenta is diagnosed in the second trimester, repeat sonography should be obtained in the early third trimester at 32 weeks. Finally, anterior placenta previa is less likely to migrate away from the cervical os than posterior placement