ABSTRACT

CORRESPONDING AUTHOR:
Dr. M. Yousuf Sarwar,
Department of Anatomy,
Katihar Medical College,
Katihar-854105,
Bihar, India.
E-mail: drmysarwar@gmail.com

ABSTRACT: INTRODUCTION: The umbilical cord is a narrow tube like structure that forms connecting link between foetus and placenta. The umbilical cord begins to form at five weeks after conception, becomes progressively longer until 28 weeks of pregnancy contains two arteries and one vein surrounded by wharton’s jelly enclosed in a layer of amnion. Abnormalities in the development and site of attachment of umbilical cord can cause problems which have the potential to affect maternal and foetal health. AIMS AND OBJECTIVES: The purpose of this study is to analyze the site of attachment of umbilical cord to the placenta by dissection method and to correlate them with any abnormalities of the mother and foetus. MATERIALS AND METHODS: A total of 150 specimens were collected from Katihar Medical College during the period of 2014-2015 and subjected to thorough examination. Details were recorded and analyzed. RESULTS: Study showed Ecentric attachment of umbilical cord 66%, Central attachment 24%, Marginal 08% and Velamentous 02%. CONCLUSION: Variations in the placental attachment of umbilical cord are also associated with abnormalities in the foetus as well as the mother. Early examination of the placenta can yield information that may be important in the immediate and later management of mother and infant.

KEYWORDS: Umbilical cord, Attachment, Eccentric, Marginal.

INTRODUCTION: The umbilical cord is a narrow tube-like structure which connects the developing baby to the fetal surface of placenta. The umbilical cord contains three blood vessels; two arteries and one vein surrounded by Wharton’s Jelly all enclosed in a layer of amnion. The deoxygenated foetal blood leaves the foetus in two umbilical arteries that pass through the umbilical cord. When they reach the foetal surface of the placenta, these vessels divide into many branches which enter the chorionic villi. The oxygenated blood returns to the foetus via the venules and veins in the chorionic villi that join to form the umbilical vein. The umbilical cord begins to form at five weeks after conception which becomes progressively longer until 28 weeks of gestation, reaching an average length of 55-65 cm long with outer amniotic epithelium.

Microscopically the umbilical cord arteries composed of double layered muscular wall, no internal elastic lamina while the umbilical vein larger in diameter, thin wall with single layer of disorganized circular smooth muscle and an internal elastic lamina.

The cord deserves attention right from the first trimester. A number of abnormalities in the development and site of insertion can affect the umbilical cords which have the potential to affect maternal and foetal health.

Variations in the attachment of umbilical cord are thought to result from the process known as trophotropism in which the chorionic frondorum or the early placenta ‘migrate’ with advancing gestation to ensure a better blood supply from a richly vascularized area. The umbilical cord insertion to the placenta is divided as central/ eccentric, marginal and velamentous as it relates to the chorionic plate. Another type of variation is furcate insertion in which umbilical cord branch before its insertion to placenta.

If the umbilical cord is inserted within 2 cm from the placental edge, it is considered as marginal attachment. This is associated with IUGR, preterm labour. In velamentous type cord insertion to the chorio-amniotic membrane of placenta. This anomaly is associated with low birth weight, low apgar score, growth retardation, oesophageal atresia, spina bifida, VSD. Furcate placenta has greater volume than normal villi, villous trophoblast and syncytial knots. Furcate placenta is more prone to early delivery because they are heavier more voluminous villi with more trophoblast & syncytial knots.

MATERIALS AND METHODS: The materials for the study were collected from the obstetrics and gynecology department of Katihar Medical College, Katihar, Bihar and the work has been conducted in the department of Anatomy during the year 2014-2015. A total of 150 normal specimens of placenta with intact umbilical cord were collected and preserved in 10% formalin.

The specimens were cleared, dissected and observed for placental attachment of umbilical cord. Variations in site of attachment of umbilical cord were noted in all the specimens and measured its distance from the placental margin and photographed. Distance were recorded and analyzed.

RESULTS: In all specimens the pattern of placental attachment of umbilical cord were observed and studied. Among the 150 specimen, 99(66%) placenta showed the Eccentric and 36(24%) Central attachment of umbilical cord which was considered as normal. Marginal insertion 12(08%) and velamentous 03(02%) from the total observed placentae.

Battledore placentae were associated with the anomalies of placenta as well as related to abnormal conditions of the mother and foetus. More number of abnormalities in foetus was seen in placentae with abnormalities compared with normal placentae.

Fig. 1: Site of insertion of umbilical cord.

A-     Eccentric

Central

c-     Marginal

DISCUSSION: Abnormalities in the placental insertion of umbilical cord has been associated with number of complication of pregnancy and foetal outcome due to compression of umbilical vessels. These abnormalities are also associated with IUGR, preterm labour, oesophageal atresia, VSD, spina bifida and so on.

In the present study we have evaluated the variation in placental attachment of umbilical cord which may be clinically important as stated earlier.

Among the 150 specimen, 99(66%) showed eccentric attachment, 36(24%) central and 12(08%) were marginal and rest 3(02%) were velamentous insertion of umbilical cord.

Donald N Di Salvo et al conducted sonographic studies and observed 38(70.37%) normal insertion, 12(22.2%) marginal and 4(7.41%) velamentous insertion.

W. Sepulreda et al assessed the placental insertion of umbilical cord in 138 specimens by ultrasonography and reported 127(92.02%) normal, 10(7.2%) marginal and 1(0.75%) velamentous type of cord insertion.

Variation (Eccentric, marginal and vlamentous) in the placental attachment of umbilical cord is probably as a result of trophotrophism.

Among 12 battledore placenta, there is history of abortion in 2, type 2 diabetes mellitus in 1, preeclampsia in 1 and anencephaly in 1 specimen.

Among 3 velamentos placentae, type 2 diabetes mellitus is associated in 1 case. Battledore placentae were associated with the anomalies of placentae as well as related to abnormal conditions of the mother and foetus.

CONCLUSION: Variations in the placental attachment of umbilical cord are associated with abnormalities in the foetus as well as the mother. Early prenatal diagnosis of umbilical cord insertion anomalies gives an insight into the congenital anomalies. Abnormal placental attachments of umbilical cord are one of the causes of intrauterine death of foetus due to tear of umbilical vessels during labour.

Therefore, it is essential that the delivering physician performs a thorough, accurate examination of the placenta and in case of doubt; radiologist or anatomist should be consulted to confirm the diagnosis. Such early examination of the placentae can yield information that may be important in the immediate and later management of mother and foetus.

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