Placenta - Abnormalities: Difference between revisions

From Embryology
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===Velamentous Cord Insertion===
===Velamentous Cord Insertion===
(velamentous insertion) Clinical term for describing a placental abnormality where the placental cord inserts into the chorion laeve (placental membranes) away from the edge of the placenta. The placental vessels are therefore unprotected by Wharton's jelly where they traverse the membranes before they come together into the umbilical cord. This can cause hemorrhage if the vessels are damaged when the membranes are ruptured prior to birth. The condition is more common in monozygotic twins (15%) and triplets.
(velamentous insertion) Clinical term for describing a placental abnormality where the placental cord inserts into the chorion laeve (placental membranes) away from the edge of the placenta. The placental vessels are therefore unprotected by Wharton's jelly where they traverse the membranes before they come together into the umbilical cord. This can cause hemorrhage if the vessels are damaged when the membranes are ruptured prior to birth. The condition is more common in monozygotic twins (15%) and triplets.
==Placental Mesenchymal Dysplasia==
Due to a similar "grape-like" placental appearance, this rare disorder placental mesenchymal dysplasia has been mistaken both clinically and macroscopically for a partial hydatidiform molar pregnancy. The disorder also has a high incidence of both intrauterine growth restriction (IUGR) and fetal death.
Current research suggests that placental cells may be originated from a mixed population of androgenetic (paternal-derived genome only) and biparental cells. This means that chorionic villus sampling can provide a differential diagnosis between this and a partial mole.<ref><pubmed>20503241</pubmed></ref>


==Pre-eclampsia==
==Pre-eclampsia==
Line 85: Line 91:


Recent research using a large population study in Norway has shown a strong generational association such that daughters of women who had pre-eclampsia during pregnancy had more than twice the risk of pre-eclampsia themselves. The paper concludes "Maternal genes and fetal genes from either the mother or father may trigger pre-eclampsia. The maternal association is stronger than the fetal association. The familial association predicts more severe pre-eclampsia."<ref><pubmed>16169871</pubmed></ref>
Recent research using a large population study in Norway has shown a strong generational association such that daughters of women who had pre-eclampsia during pregnancy had more than twice the risk of pre-eclampsia themselves. The paper concludes "Maternal genes and fetal genes from either the mother or father may trigger pre-eclampsia. The maternal association is stronger than the fetal association. The familial association predicts more severe pre-eclampsia."<ref><pubmed>16169871</pubmed></ref>
References
Sibai BM.    [See Related Articles] Diagnosis, prevention, and management of eclampsia. Obstet Gynecol. 2005 Feb;105(2):402-10.
Skjaerven R, Vatten LJ, Wilcox AJ, Ronning T, Irgens LM, Lie RT.    [See Related Articles] Recurrence of pre-eclampsia across generations: exploring fetal and maternal genetic components in a population based cohort. BMJ. 2005 Sep 16
Links: Australia Australian Action on Pre-eclampsia (voluntary organisation providing support and information to families who have suffered from pre-eclampsia)
Placental Mesenchymal Dysplasia
Due to a similar "grape-like" placental appearance, this rare disorder placental mesenchymal dysplasia has been mistaken both clinically and macroscopically for a partial hydatidiform molar pregnancy. (More? Week 2 - Hydatidiform mole) The disorder also has a high incidence of both intrauterine growth restriction (IUGR) and fetal death.
(More? Parveen Z, Tongson-Ignacio JE, Fraser CR, Killeen JL, Thompson KS. Placental mesenchymal dysplasia. Arch Pathol Lab Med. 2007 Jan;131(1):131-7.)


==Hydatidiform Mole==
==Hydatidiform Mole==

Revision as of 14:33, 18 October 2010

Notice - Mark Hill
Currently this page is only a template and will be updated (this notice removed when completed).

Introduction

Placental implantation abnormalities

The placenta is a mateno-fetal organ which begins developing at implantation of the blastocyst and is delivered with the fetus at birth. As the fetus relies on the placenta for not only nutrition, but many other developmentally essential functions, the correct development of the placenta is important to correct embryonic and fetal development.

Abnormalities can range from anatomical associated with degree or site of inplantation, structure (as with twinning), to placental function, placento-maternal effects (pre-eclampsia, fetal erythroblastosis) and finally mechanical abnormalities associated with the placental (umbilical) cord.

This current page lists some abnormalities associated with the placenta and also provides links to other resources. (See also Week 2 Abnormalities - Hydatidiform mole)

Placenta Links: placenta | Lecture - Placenta | Lecture Movie | Practical - Placenta | implantation | placental villi | trophoblast | maternal decidua | uterus | endocrine placenta | placental cord | placental membranes | placenta abnormalities | ectopic pregnancy | Stage 13 | Stage 22 | placenta histology | placenta vascular | blood vessel | cord stem cells | 2013 Meeting Presentation | Placenta Terms | Category:Placenta
Historic Embryology - Placenta 
1883 Embryonic Membranes | 1907 Development Atlas | 1909 | 1910 Textbook | 1917 Textbook | 1921 Textbook | 1921 Foetal Membranes |1921 human | 1921 Pig implantation | 1922 Single placental artery | 1923 Placenta Review | 1939 umbilical cord | 1943 human and monkey | 1944 chorionic villus and decidua parietalis | 1946 placenta ageing | 1960 first trimester placenta | 1960 monkey | 1972 Placental circulation | Historic Disclaimer

Placenta Accreta

Abnormal adherence, with absence of decidua basalis. The incidence of placenta accreta also significantly increases in women with previous cesarean section compared to those without a prior surgical delivery.[1][2]

See WebPath images: Placenta accreta, microscopic

Placenta Increta

Placenta Increta occurs when the placenta attaches deep into the uterine wall and penetrates into the uterine muscle, but does not penetrate the uterine serosa. Placenta increta accounts for approximately 15-17% of all cases.

Placenta Percreta

Placental villi penetrate myometrium and through to uterine serosa. See clinical article on the laparoscopic management of placenta percreta. [3]

Placenta Previa

Galletti1770 placenta previa.jpg Placenta previa - anterior.jpg
Model of Placenta Previa (Italian terracotta from 1770) Ultrasound showing placenta position (upper arrow) in relation to cervix os (lower arrow)

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 (More? Abruptio Placenta)

Ultrasound screening programs during 1st and early 2nd trimester pregnancies now include placental localization. Diagnosis can also be made by transvaginal ultrasound.

See also recent advances in the management of placenta previa. [4][2]

Vasa Previa

Vasa previa (vasa praevia) placental abnormality where the fetal vessels lie within the membranes close too or crossing the inner cervical os (opening). This occurs normally in 1:2500-5000 pregnancies and leads to complications similar too those for placenta previa.[5][2]

Type II is defined as the condition where the fetal vessels are found crossing over the internal os connecting either a bilobed placenta or a succenturiate lobe with the main placental mass.[6]

There are suggestions that colour doppler ultrasound can be used to visualise the blood vessels in high-risk cases and if required elective caesarean performed at 35–36 weeks in cases diagnosed as vasa praevia.[7]

Some recent evidence of successful in utero laser ablation of type II vasa previa at 22.5 weeks of gestation.

Management of vasa previa

The following text is from a recent paper identifying the Canadian guidelines for the management of vasa previa.[8]

  1. If the placenta is found to be low lying at the routine second trimester ultrasound examination, further evaluation for placental cord insertion should be performed. (II-2B)
  2. Transvaginal ultrasound may be considered for all women at high risk for vasa previa, including those with low or velamentous insertion of the cord, bilobate or succenturiate placenta, or for those having vaginal bleeding, in order to evaluate the internal cervical os. (II-2B)
  3. If vasa previa is suspected, transvaginal ultrasound colour Doppler may be used to facilitate the diagnosis. Even with the use of transvaginal ultrasound colour Doppler, vasa previa may be missed. (II-2B)
  4. When vasa previa is diagnosed antenatally, an elective Caesarean section should be offered prior to the onset of labour. (II-1A)
  5. In cases of vasa previa, premature delivery is most likely; therefore, consideration should be given to administration of corticosteroids at 28 to 32 weeks to promote fetal lung maturation and to hospitalization at about 30 to 32 weeks. (II-2B)
  6. In a woman with an antenatal diagnosis of vasa previa, when there has been bleeding or premature rupture of membranes, the woman should be offered delivery in a birthing unit with continuous electronic fetal heart rate monitoring and, if time permits, a rapid biochemical test for fetal hemoglobin, to be done as soon as possible; if any of the above tests are abnormal, an urgent Caesarean section should be performed. (III-B
  7. Women admitted with diagnosed vasa previa should ideally be transferred for delivery in a tertiary facility where a pediatrician and blood for neonatal transfusion are immediately available in case aggressive resuscitation of the neonate is necessary. (II-3B)
  8. Women admitted to a tertiary care unit with a diagnosis of vasa previa should have this diagnosis clearly identified on the chart, and all health care providers should be made aware of the potential need for immediate delivery by Caesarean section if vaginal bleeding occurs. (III-B).

Placenta Membranacea

A rare placental abnormality where either all (diffuse placenta membranacea) or part (partial placenta membranacea) is covered by chorionic villi (placental cotyledons). Clinically the abnormality presents with vaginal bleeding, in the second or third trimester or during labor, due to an associated placenta previa.[9] Ultrasound has been used to detect this condition.[10]

Links: Ultrasound

Abruptio Placenta

Represents interruption of the placenta by partial or complete separation, retroplacental blood clot formation and abnormal hemorrhage prior to delivery. There is significant perinatal mortality associated with abruptio placenta.[11]

Chronic Intervillositis

(massive chronicintervillositis, chronic histiocytic intervillositis) Rare placental abnormality and pathology defined by inflammatory placental lesions, mainly in the intervillous space (IVS), with a maternal infiltrate of mononuclear cells (monocytes, lymphocytes, histiocytes) and intervillous fibrinoid deposition.

References

Chronic intervillositis of the placenta. Jacques SM, Qureshi F. Arch Pathol Lab Med. 1993 Oct;117(10):1032-5.

Velamentous Cord Insertion

(velamentous insertion) Clinical term for describing a placental abnormality where the placental cord inserts into the chorion laeve (placental membranes) away from the edge of the placenta. The placental vessels are therefore unprotected by Wharton's jelly where they traverse the membranes before they come together into the umbilical cord. This can cause hemorrhage if the vessels are damaged when the membranes are ruptured prior to birth. The condition is more common in monozygotic twins (15%) and triplets.

Placental Mesenchymal Dysplasia

Due to a similar "grape-like" placental appearance, this rare disorder placental mesenchymal dysplasia has been mistaken both clinically and macroscopically for a partial hydatidiform molar pregnancy. The disorder also has a high incidence of both intrauterine growth restriction (IUGR) and fetal death.

Current research suggests that placental cells may be originated from a mixed population of androgenetic (paternal-derived genome only) and biparental cells. This means that chorionic villus sampling can provide a differential diagnosis between this and a partial mole.[12]


Pre-eclampsia

This condition is also known as gestational proteinuric hypertension and occurs in occurs in approximately 2 to 4% of all pregnancies. The pathogenesis of eclamptic convulsions remains unknown and women with a history of eclampsia are at increased risk of eclampsia (1-2%) and preeclampsia (22-35%) in subsequent pregnancies. "Magnesium sulfate is the drug of choice for reducing the rate of eclampsia developing intrapartum and immediately postpartum."(see Sibai BM. 2005).

Recent research using a large population study in Norway has shown a strong generational association such that daughters of women who had pre-eclampsia during pregnancy had more than twice the risk of pre-eclampsia themselves. The paper concludes "Maternal genes and fetal genes from either the mother or father may trigger pre-eclampsia. The maternal association is stronger than the fetal association. The familial association predicts more severe pre-eclampsia."[13]

Hydatidiform Mole

Hydatidiform Mole

Another type of abnormality is when only the conceptus trophoblast layers proliferates and not the embryoblast, no embryo develops, this is called a "hydatidiform mole", which is due to the continuing presence of the trophoblastic layer, this abnormal conceptus can also implant in the uterus. The trophoblast cells will secrete human chorionic gonadotropin (hCG), as in a normal pregnancy, and may appear maternally and by pregnancy test to be "normal". Prenatal diagnosis by ultrasound analysis demonstrates the absence of a embryo.

There are several forms of hydatidiform mole: partial mole, complete mole and persistent gestational trophoblastic tumor. Many of these tumours arise from a haploid sperm fertilizing an egg without a female pronucleus (the alternative form, an embryo without sperm contribution, is called parthenogenesis). The tumour has a "grape-like" placental appearance without enclosed embryo formation. Following a first molar pregnancy, there is approximately a 1% risk of a second molar pregnancy.

This topic is also covered in Week 2 - Abnormalities

Mole Types

Complete mole - chromosomal genetic material from the ovum (egg) is lost, by an unknown process. Fertilization then occurs with one or two sperm and an androgenic (from the male only) conceptus (fertilized egg) is formed. With this conceptus the embryo (fetus, baby) does not develop at all but the placenta does grow but it is abnormal and forms lots of cysts and has no blood vessels. These cysts look like a cluster of grapes and that is why it is called a hydatidiform mole (grape like). A hydatidiform mole miscarries by about 16 to 18 weeks gestational age. Since the diagnosis can be made by ultrasound before that time, it is better for you to have an evacuation of the uterus (D & C) so that there is no undue bleeding and no infection. Human chorionic gonadotropin (hCG) will assist in making the diagnosis.

Partial mole - three sets of chromosomes instead of the usual two and this is called triploidy. With such a pregnancy the chromosomal (genetic) material from the ovum (egg) is retained and the egg is fertilized by one or two sperm. Since with partial mole there are maternal chromosomes there is a fetus but because of the three sets of chromosomes this fetus is always grossly abnormal and will not survive. (Text modified from: International Society for the Study of Trophoblastic Diseases,see also JRM Gestational Trophoblastic Disease)

Tumour Growth

Like any tumour, unless removed there is a risk of progression:

Stage I: Tumor confined to uterus (non-metastatic)
Stage II: Tumor involving pelvic organs and/or vagina
Stage III: Tumor involving lungs, with or without involving pelvic structures and/or vagina
Stage IV: Tumor involving distant organs

Placental Mesenchymal Dysplasia

Due to a similar "grape-like" placental appearance, this rare disorder has been mistaken both clinically and macroscopically for a partial hydatidiform molar pregnancy. This disorder also has a high incidence of intrauterine growth restriction (IUGR) and fetal death.

Twin Pregnancy Mole

Hydatidiform mole and co-existent healthy fetus is a very rare condition with only 30 cases documented in detail in the literature.[14]

Links: International Society for the Study of Trophoblastic Diseases | Sydney Gynaecological Oncology Group Gestational Trophoblastic Disease | The Journal of Reproductive Medicine Gestational Trophoblastic Disease (1998) | Dana-Farber Cancer Institute Gynecologic Oncology Program

Cord Abnormalities

Cord Vessel Number

Placental cord ultrasound 02.jpg
Cord with one artery and one vein

Cord Knotting

Placental cord true knot

There are few abnormalities associated with umbilical cord development, other that abnormally short or long cords, which in most cases do not cause difficulties.

In some cases though, long cords can wrap around limbs or the fetus neck, which can then restrict blood flow or lead to tissue or nerve damage, and therefore effect develoment.

Cord knotting can also occur (1%) in most cases these knots have no effect, in some cases of severe knotting this can prevents the passage of placental blood.

See WebPath images: umbilical cord knot 1 | umbilical cord knot 2 | Pseudoknot of umbilical cord, gross

References

Umbilical cord torsion

Rare umbilical cord torsion, even without knot formation can also affect placental blood flow, even leading to fetal demise.[15]

See also WebPath images: Torsion of umbilical cord, gross | Torsion of umbilical cord, with fetal demise, gross

Cord Length

Fetal Erythroblastosis

This disease is also called Haemolytic Disease of the Newborn, an immune problem from fetus Rh+ /maternal Rh-, leakage from fetus causes anti-Rh antibodies, which is then dangerous for a 2nd child.

RHESUS BLOOD GROUP

Placental Infections

Listeria maternal-fetal barrier

Several infective agents may cross into the placenta from the maternal circulation, as well as enter the embry/fetal circulation. The variety of bacterial infections that can occur during pregnancy is as variable as the potential developmental effects, from virtually insignificant to a major developmental, abortive or fatal in outcome.

Placental Malaria

Pregnant women have an increased susceptibility to malaria infection. Malarial infection of the placenta by sequestration of the infected red blood cells leading to low birth weight and other effects. There are four types of malaria caused by the protozoan parasite Plasmodium falciparum (main), Plasmodium vivax, Plasmodium ovale, Plasmodium malariae). This condition is common in regions where malaria is endemic with women carrying their first pregnancy (primigravida).


Plasmodium falciparum

(More? Abnormal Development - Malaria Infection)

References: Beeson JG, Duffy PE. The immunology and pathogenesis of malaria during pregnancy. Curr Top Microbiol Immunol. 2005;297:187-227. | Brabin BJ, Romagosa C, Abdelgalil S, Menendez C, Verhoeff FH, McGready R, Fletcher KA, Owens S, D'Alessandro U, Nosten F, Fischer PR, Ordi J. The sick placenta-the role of malaria. Placenta. 2004 May;25(5):359-78.

Links: Brown University - Maternal Malaria | CDC - Malaria

Placental Membranes

There are few documented abnormalities associated with fetal membranes. Ultrasound measurement of abnormal yolk sac size/shape in early embryonic development has been suggested as an indicator of early gestational loss. The most common literature described abnormalities are those associated with abnormal vasularization of the chorion.

Placental Pathology

The following pathology information from[16].

Chronic Villitis

This condition can occur following placental infection leading to maternal inflammation of the villous stroma, often with associated intervillositis. The inflammation can lead to disruption of blood flow and necrotic cell death.

Massive Chronic Intervillositis

(MCI) The maternal blood-filled space is filled with CD68-positive histiocytes and an increase in fibrin, occuring more commonly in the first trimester.

Meconium Myonecrosis

The prolonged meconium exposure leads to toxic death of myocytes of placental vessels (umbilical cord or chorionic plate).

Neuroblastoma

A fetal malignancy that leads to an enlarged placenta, with tumor cells in the fetal circulation and rarely in the chorionic villi.

Thrombophilias

(protein C or S deficiency, factor V Leiden, sickle cell disease, antiphospholipid antibody) This condition can generate an increased fibrin/fibrinoid deposition in the maternal or intervillous space, this can trap and kill villi.

International Classification of Diseases

Ninth Revision, Clinical Modification16 codes for 5 selected complications of pregnancy

  • Preeclampsia (642.4, 642.5)
  • Eclampsia (642.6, 642.7)
  • Abruptio placentae (641.2)
  • Placenta previa (641.0, 641.1)
  • Postpartum hemorrhage (666.0–666.2)

References

  1. <pubmed>9701688</pubmed>
  2. 2.0 2.1 2.2 <pubmed>16582134 </pubmed>
  3. <pubmed>20129349</pubmed>
  4. <pubmed>15534438</pubmed>
  5. <pubmed>16582134</pubmed>
  6. <pubmed>18050017</pubmed>
  7. <pubmed>19003654</pubmed>
  8. <pubmed>19772710</pubmed>
  9. <pubmed>12532260</pubmed>
  10. <pubmed>1883791</pubmed>
  11. <pubmed>16021079</pubmed>
  12. <pubmed>20503241</pubmed>
  13. <pubmed>16169871</pubmed>
  14. <pubmed>18273627</pubmed>
  15. <pubmed>7966052</pubmed>
  16. <pubmed>18384216</pubmed>

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Cite this page: Hill, M.A. (2024, March 28) Embryology Placenta - Abnormalities. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Placenta_-_Abnormalities

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