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MA 5.4 NUMA SI GA RBHAVIKA S KRAM Completed Fetus in Prsava- Vastha Rasanufj*^SIK GARBHAVRUDHI

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MA 5.4 NUMA SI GA RBHAVIKA S KRAM Completed Fetus in Prsava- Vastha Rasanufj*^SIK GARBHAVRUDHI MA 5.4 NUMA SI GA RBHAVIKA S KRAM Completed Fetus in prsava- vastha rASANUfJ*^SIK GARBHAVRUDHI I N Ayurvedic classics, the embryonit*««,^jie.uaJf6f'ment has been narrated monthwise while the modern Medical literature has considered the development of embryo in months as well as in weeks. "KALALAV/ASTHA (first month) ^ T ^.?1T. 3/14 Susruta and both Vagbhattas us.ed the word 'K a la la ' forthe shape of the embryo in the first month of intrauterine life. I Caraka has described the first month embryo as a mass ofcells like mucoid character in which all body parts though present are not conspicuous. T Incorporated within it all the five basic elements, ' Panchmah'abhuta' i.e. Pruthvi, Ap , Teja, Vayu and Akas . During the first month the organs of Embryo are both manifested and latent. It is from this stage of Embryo that various organs of the fetus develop, thus they are menifested. But these organs are not well menifested for differentiation and recongnisiation hence they are simultenously described as latent as well as manifested. 3T.f.^. 1/37 Astang - hrudayakar has described the embryo of first month as 'Kalala' but in 'avyakta' form. The organs of an embryo is in indistingushed form. Modern embryologist has described this first month development in week divisions. First Week - No fertile ova of the first week has been examined. Our knowledge of the first week of I embryo is of other mammals as amphibian. The egg is fertilised in the upper end of the uterine tube, and segments into about cells, before it I passes in to the uterus, it continues to segment and develop into a blastocyst (Budbuda) with a trophoblastic cells and inner cell mass. I Second Week - The blastocyst enlarges loses it's Zona pellucida I and becomes implanted in the uterine mucosa. The trophoblast enlarges and develop an activity invading outer syncytiotrophoblast and inner cytotrophoblast and forms primitive chorionic villi into which first mesoderm then blood vessels grow. The inner cell mass becomes the embryonic disc amnion and yolk sac. The primitive streak differentiates and then mesoderm and notochord are formed. Third Week - During the early part of third week the neurofolds appear. The allantoic duct begins to develop. The yolksac enlarges, and blood | vessels begin to form. Before the end of the i i week, the neuro folds begin to unite. The | Neurenteric canal opens. The primitive segments ^ begin to form. The changes during this week occur with great rapidity. | I Fourth Week- During the fourth week, the nural folds close, | s' the primitive segments increase number. The 5 brachial arches appear and the connection of yolk sac with the embryo becomes considerbly | narrowed so that the embryo assumes a more | definite form . I I Major events in Ilnd week - Implantation of blastocyst is completed by the 12 th day of development. The uterine decidua is named as deciduabesalis at the embryomic pole, decidua capsularis around the rest of the blastocyst and decidua paritalis which lines the rest of the uterine cavity. Decidua besalis forms the site of the future placenta. The Trophoblast differentiates into th syncytiotrophoblast and cytotrophoblast on 8 day. The successive development of trophoblastic lacunae, trabeculae, | utero-placental circulation, primary villi, and intervilous space | take place between 9 to 13 day. The intervillous space are | now filled with maternal blood. )f) The embryoblast defferentiates into bilaminar germdisc, ectodermal and endodermal layers. The germ disk is | sandwiched between the two vesicles. Both vesicles are enveloped by splanchnopleuric layer of extra-embryonic mesoderm. In the I| I later part of Ilnd week the primary yolk sae converts into secondary yolk sac. I i I I S Major events in Ilird week - The flattened germ disc changes in shape from circular to oval, and then pear shaped area with a broad cephalicand a narrow caudal end. The primitive streak appears in the caudal part of the germ disc. The cephalic end of the streak is enlarged to | form primitive node or Hensen's node. The notochord is visible on 17^^ or 18*^*^ day. I The successive processes in the development of notochord are | canalised notochordal process, formation of the neurenteric canal. | But convertion of bilaminar germ disc to trilaminar one is the I I achievement of Ilir d week. { Caudal to the cloacal membrane at the k I allanto-enteric diverticulum arises from the dorsi-caudal area of I the yolk sae extends into connecting stalk. I Primary choriaonic villi are changed to secondary I v illi with the appearance of a central core of primary mesoderm | and tertiary v illi with the advent of the fetal blood vessels in | the mesoderml core. "GHANAVASTHA" (Embryonic period) According to modern science this period extend th th, from the begining of the 4 week to the end of the 8 week. Out of the trilaminar area, the ectodermal layer provides I protection, the endodermal layer is meant for nutrition, andI mesodermal layer is primarily available for function of Skeletan, | tissues, muscles, and blood vascular system. Thus during Ilnd | month all major organs and tissues are laid down from the germ layers and external appearance of the embryo is recognisable with the development of the face and the limbbuds. Between 20 to 30 days most of the Somites appear. After the somite period the age can be calculated in ' CR' ( Crown Rump ) or CH ( Crown Heel ) length. On average the embryo at the age of 32 days is 5 mm in CR length, and it may increase 1 mm/day upto 55 days and there after 1.5 mm/day upto the full term. i I f Rudimentary upper limb develop first then lower k limb. The somatopleuric layer of the lateral plate extends within I the limbbuds as a mesodermal core and later differatiate to form || bones, and joints. The heart increases greatly in size, producing | a prominent bulge in the brachial region. I| I I I I i The recent concept about the development of trophoblast in vitro, from the blastocyst containing varying amounts of inner cell mass is available. It has been observed when intact blastocysts are cultured in vitro in medium supplimented the total calf serum, trophoblast cells proliferate and undergoes that cell transformation such as occur in vivo. If the amount of inner cell mass in the blastocysts is decreased by the culture with - HI - Thymidine , then giant cell transformation occur normally but proliferation is reduced. In the absence of giant cell mass no proliferation occures and giant cells transformation is more rapid than undamaged blastocyst. ^ T 3 / 1 4 . In Ayurveda the real work of Panchmahabhuta |I I start with the help of Dhatvagni and embryo now turns to some GHANA (solid) state. Which may be Pinda (o\=al), Peshi fi (elonggated) or Arbudasama (rounded). The external appearance i of embryo now turns to Pind (ball type) or Peshi (elongated) or | Arbuda (rounded). These shapes also give the hint of future | embryonic sex. If this solid mass had oval (Pinda) shape the | i I i born child would be male, if elongated (Pesi) the female and with L I Susruta and his followers corroborating the above views have elaborated that these accumulated Mahabhutas get processed by combined action of - Slesma, Pitta and Vayu and become solid. Susruta also suggested some herbal medicine known as 'Punsanvan Karma' for the male - sex embryo. According to modern anatomists, in the 5 week of intrauterine life the embryo becomes markedly curved, the head increases greatly in size and the limb buds show segments, the brachial arches undergo profound changes and partly disappear. The superficial nose, eye and erudiments become prominent. In the 6 week of intrauterine life, the curvature of embryo is further diminished. The brachial grooves eruept the first have p appeared and the rudiments of the fingers and toes can be | recognised. But in the 7 and 8^^ week the flexure of the head | is greatly reduced and the neck is somewhat lengthened. The | I upper lip is completed and nose is more prominent. The nostrils » I are directed forward and plate is not completely developed. The | eyelids are present in the shape of folds and below the eye and | the different parts of the aurical are distinguishable. By the end | of Ilnd month the fetus measures from 2.7 to 3 cm in length. | iI / •/ "PANCH-PINDAKAWASTHA" In Ayurvedic classics this period is known as ' Panchpindakawastha because the shape of fetus is similar to five buds stage. A head (Sir) upper extrimities (Hastas) and lower extrimities (Pada) appear in this month. Carka, Susruta and Vagbhata described the same condition with little difference. 3/14. 4/1 I . TTT% ft ^ T 3T.f.?IT.^. 1/54. According to Susruta in the 3^'^ month, there is | growth of fourlimbsbuds and onebud for head, other than this all | the external details of the body parts are visible in the fetus. I^ V^hile Carak did not mention about the limbbuds r I II I and head. He says that all the 'Indriyas' are visible. This | version it self speaks that all the four sense organs excepting skin which are present in the head region are visible along with the limbbud, which are ' Karmendriya' . Carak agrees with the view of Susruta that all the ’nody parts collectively develop in this month. ^ 5¥Tr^F^f^ T 3T.g.5n. 2/13- Similar description is in' the 'Astang Sangraha' about the development of four limbbuds and one headbud is available. According to modern embryologist the head is , extended and the neck is lengthened. The eyelids meet and fuse, remain closed until the end of 6*"'^ month.
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