Describe the adaptations of the human placenta and foetus to improve oxygen availability
The presence of placenta is critical for the development of the foetus as placenta provides the materno-foetal connection and facilitates the exchange of vital nutrients from the mother to foetus. Gaseous exchange through the materno-foetal barrier is very vital for the survival of the foetus during pregnancy and the proper development of organs of the foetus. Hence, placenta is significant to aid the development of foetus as it acts as an organ that allows materno-foetal gas exchange. The blood-blood barrier between placenta and foetus requires a few adaptations to maximize the efficiency of gaseous exchange.
Firstly, the area of exchange surface for
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The materno-foetal blood flow is considered very important as oxygen is delivered whilst dissolved in the blood. The matreno-foetal blood flow can be described as the ‘counter current flow’ because the maternal and foetal capillaries are situated in the opposite directions. This facilitates the oxygen transport process greatly compared to the ‘concurrent flow’ where the maternal and foetal capillaries are parallel to each other (Ahokas, R. A., McKinney, E. T., 2009). With the ‘counter current flow’, the maximum transfer of oxygen can be attained as the maternal capillary extends to the entire length of the foetal capillary. Hence, very efficacious transport of oxygen can take …show more content…
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In most hospital delivery rooms, the doctors will routinely clamp and sever the umbilical cord with in fifteen to thirty seconds of the mother giving birth. When clamping the cord, the doctors will clamp the cord in two places, one close to the infant and then again in the middle of the cord another clamp. By delaying the clamping, fetal blood in the placental transfusion can provide the infant with an additional thirty percent more blood volume and up to sixty percent more blood cells (McDonald, S., & Middleton, P., 2009). This reduces the risk of the hemorrhaging that could occur after birth. But with new ongoing studies, it is said that by delaying the clamping of the cor...
The fetus begins to develop the type II alveoli at 22nd to 24th week of gestation, however these immature alveoli are incapable of supplying enough surfactant to meet the infant's respiratory needs. The fetus surfactant production begins to become adequate at the middle terminal stage of alveoli development and production becomes optimal at the 34th-to-36th week. (Porth, 1306) There are four types of surfactant produced by the type 2 alveoli known as primary surfactant proteins SP-A, SP-B, SP-C, and SP-D. SP-A and SP-D roles are inhibiting production of surfactant i...
Introduction: The purpose of this lab is to have a better understanding of the internal and external anatomy. The reasons for performing this lab is that pigs are similar to humans because they have skin, omnivores and as fetus they receive nutrients from an umbilical cord connected to the mother. As well as the similarities to human organ systems. The hypothesis of this lab is if the fetal pig has a similar organ system of a human and assuming those organs will be in the same locations as in a human then the organ systems should operate in the same fashion. Based on what I’ve learned from this lab and what I’ve learned during lecture I predict that the fetal pigs nervous and circulatory system would operate and look the same way as in a human.
Childbirth is nothing short of a miracle. The placenta—the organ connecting a developing fetus to the uterine wall and allowing for waste elimination, nutrient uptake and gas exchange via the mother's blood supply—filters most harmful substances that threaten an embryo, though some may still pass on to the fetus. These harmful substances, called “teratogens,” range from environmental chemicals to the transmission of maternal diseases, and can negatively impact the normal developmental cycle of a fetus. The title “teratogen,” however, refers to any substance or chemical exposure with the potential to cause birth defects in prenatal development. Exposure to teratogens can result in a broad spectrum of physiological and psychological issues in later life, including malformations of the body.
As defined by Lowdermilk, Perry and Cashion, preterm labor is “cervical changes and uterine contractions occurring between 20 and 37 weeks of pregnancy”. Preterm birth is a dramatic event causing distress for both the child and parents. There is a significant amount of information available on the risk factors related to preterm labor. Seeing the ineffectiveness of interventions directed towards known risk factors emphasizes the lack of maternal understanding of possible underlying pathways.
The circulatory system and respiratory system share a highly important relationship that is crucial to maintaining the life of an organism. In order for bodily processes to be performed, energy to be created, and homeostasis to be maintained, the exchange of oxygen from the external environment to the intracellular environment is performed by the relationship of these two systems. Starting at the heart, deoxygenated/carbon-dioxide (CO2)-rich blood is moved in through the superior and inferior vena cava into the right atrium, then into the right ventricle when the heart is relaxed. As the heart contracts, the deoxygenated blood is pumped through the pulmonary arteries to capillaries in the lungs. As the organism breathes and intakes oxygenated air, oxygen is exchanged with CO2 in the blood at the capillaries. As the organism breathes out, it expels the CO2 into the external environment. For the blood in the capillaries, it is then moved into pulmonary veins and make
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Obstetric Ultrasound -- a Comprehensive Guide to Ultrasound Scans in Pregnancy. Mar. 2006. Web. 13 Apr. 2011. .
With the onset of labor the hormone estrogen is elevated so that it higher than progesterone, thereby reducing the relaxing effects of progesterone on the muscle. The rise in estrogen levels increases the uterus sensitivity to other factors that will stimulate uterine contractions. These include prostaglandins from the fetal membranes, and oxytocin from the mother’s posterior pituitary gland. The estrogen also increases the number of gap junctions which are connections that allow the uterine muscles to contract as a unit. Prostaglandins, which are produced by the deciduas and membranes, help to prepare the uterus for oxytocin stimulation at term. Once labor has begun, oxytocin helps to maintain labor. Oxytocin does not alone initiate labor, but it may work in conjunction with other substances. There is also evidence of fetal oxytocin secretion. Oxytocin receptors in the uterus, at the start of labor, increase considerably and reach their peak at the time of delivery. The oxytocin will have little effect if the receptors on the uterine muscle are not developed. The fetus, it seems, also plays a role. The fetal membranes release prostaglandins in large amounts during labor. Along with the fetal oxytocin concentrations released, fetal cortisol is also released in large amounts due to the fetal adrenaline. The release of cortisol acts as a possible uterine stimulant. For labor
The process of human development is very complex. It is a continual process, providing gradual development for the fetus. Some of the most important factors to fetal development such as blood flow, heart beats, muscle development, and brain activity can all be determined within the first seven weeks of pregnancy (Baby Developme...
New technologies are being developed every day. The latest advance in fetal monitoring is the fetal oxygen monitor: “A device that directly measures fetal oxygen saturation during labor and delivery is now available and has the potential to reduce the number of Cesarean sections performed for non-reassuring heart rates.” (Mechcatie) The article by Mechcatie describes the monitor extremely well: “The device’s sensor, located at the end of a flexible tube, is made of pliable plastic and is inserted through the cervical os until it lies along the fetal cheek, where the pressure of the uterine wall keeps it in place during labor. The sensor shines light into the fetal skin and computes the oxygen saturation by measuring the color of the reflected light coming through the blood cells.”
Abortion is a decision every person should decide for themselves. The major arguments against abortion are how a fetus is a person; a fetus has rights; and it is morally impermissible to take a life. Many consider abortion to be equivalent to murder. However, a fetus is not a person. There are important traits one most hold to be a person, 1) self-awareness, one must be able to make decisions regarding themselves 2) being able to converse with others and hold a relationship 3) consciousness, one must be able to make rational decisions and have thought (Warren). On important aspect of being person is the ability to be aware of its surroundings and decision making. Being a pregnant is not a situation everyone gets to experience and the decision to abort a pregnancy should be left up to the women. A woman has a right to her body and should be able to make decisions concerning herself with no outside judgment.
Unlike vaginal birth delivery, the process of a cesarean delivery is quite different, but just as safe as giving vaginal birth (Taylor, 1). When delivering a baby using the cesarean method, there are two ways anesthetic can be used. The women can be put into an unconscious state using the anesthetic, therefore she will be asleep during the entire operation and her coach may not be present. The other way for the anesthetic to be used would be in an epidural or spinal block to temporarily numb the woman from her waist down. In this case the mother will be awake and her coach may be present to give her extra support. Once the anesthetic is working, an incision is made in the abdomen either horizontally or vertically, depending on the reason for the cesarean delivery. A vertical incision is made when the baby is in trouble and needs to be out as quickly as possible, when there is more time the horizontal incision is used. The baby is then lifted out of the uterus and gone for the APGAP procedure. The placenta is then removed and the mother’s reproductive organs are examined before closing the incision (Taylor, 1).
Preterm birth is defined as ‘any neonate whose birth occurs before the thirty seventh week of gestation’1 and represents approximately eight percent of all pregnancies1-4. It is eminent that these preterm infants are at risk of physical and neurological delay, with prolonged hospitalisation and an increased risk of long-term morbidity evident in prior literature3, 5-13. Innovative healthcare over the past thirty years has reduced mortality significantly14, with the survival rate of preterm infants having increased from twenty five percent in 1980 to seventy three percent in 200715. Despite, this drop in mortality long-term morbidity continues to remain within these surviving infants sparking a cause for concern15, 16.
Every woman when pregnant has a 3-5% chance of having a baby born with a birth defect, and these chances increase when the developing fetus/ embryos are exposed to teratogens, whether it’s intentional or unintentional (Bethesda (MD), 2006). Teratogens can cause severe birth defects, malformations, or terminate the pregnancy altogether (Jancárková, & Gregor, 2000). The placenta is known as an effective barrier from any detrimental pathogen that can potentially hurt the fetus. The timing of exposure of any teratogen is critical to the impact of prenatal development (Bethesda (MD), 2006). The most vulnerable time of the fetus for severe damage is during early pregnancy when all the major organ and central nervous system (CNS) are developing. Miscarriages have an important role in keeping a pregnancy from evolving when there is something serious going on with the developing fetus/embryo. Miscarriages are more common than we think and are the most familiar type of pregnancy loss (Bethesda (MD), 2006).