Cerebral Palsy Essay, Research Paper
The Effects Multiple Births Have on Outcomes of Cerebral Palsy in Infants
Cerebral palsy is typically characterized as a disorder caused by injuries to the cerebrum, the part of the brain responsible for higher mental functions, sensations, and voluntary muscle actions (7). Symptoms of cerebral palsy vary by severity of the disease, and include seizures, involuntary muscle contractions, difficulty sucking or feeding, irregular breathing, delayed development of motor skills, motor-mental retardation, mental retardations, speech abnormalities, visual abnormalities, hearing abnormalities, spasticity, progressive joint contractures, limited range of motion, and peg teeth (7). These symptoms are usually evident by age two and sometimes as early as three months, depending on severity. Cerebral palsy is a non-progressive disease; meaning symptoms directly resulting from the disease do not worsen over time (7). Initially, cerebral palsy was thought to be a result of birth asphyxia and trauma, but more recent studies have proven that birth asphyxia is an extremely uncommon cause of this disease. Studies show that hypoxia (low oxygen) to the damaged area of the brain, which results in cerebral palsy (7). Premature infants have a much greater risk of cerebral palsy than do infants that are carried to term. Premature infants are much more common in pregnancies with multiple births, therefore an increasing risk of cerebral palsy is present with the increasing number of multiple births. This is grounds for concern, considering the growing use of fertility drugs that is making multiple births much more common.
Premature babies have a significantly higher risk of having cerebral palsy than babies carried to term. As the number of infants a mother carries increases, so do the odds that the infants will be born prematurely. In a study conducted by the Western Australian Research Institute for Children, twins were 16 times more likely than singletons to weigh less than 1,500 g at birth; one in 3.3 live born infants weighing under 1,500 g was from a multiple birth. Comparable figures were not available for triplets, but the risk and stresses for triplet births are much higher than for twins (6). Because multiple pregnancies put more stress on the mother as well as the fetus, this increases the chances that the babies will be born premature as well as with cerebral palsy. “There is an increased frequency of fetal distress among cases of cerebral palsy and death, representing the increased antennal risk factors in the pregnancy” (2). Multiple pregnancies are becoming much more popular and common due to advances in fertilization-enhancing techniques. Higher numbers of babies are being born, producing higher numbers of premature infants. “The numbers of multiple births surviving the prenatal period is increasing with the increasing survival of very tiny babies” (1). Through the use of fertility drugs, multiple births are producing more premature babies, which in effect, increases an infant’s chance of having cerebral palsy.
When an infant is born prematurely, the chances of it having cerebral palsy are much higher than that of a baby carried to term. “There is an increasing prevalence of cerebral palsy in preterm infants” (3). When an infant is prematurely born, several risk factors are involved, such as antenatal, intrapartum, and neonatal care. All of these factors have been associated with cerebral palsy in preterm babies (5). In the same study by the Western Australian Research Institute for Child Health, it was found that “the prevalence of cerebral palsy was higher in babies of low birth weight in all pluralities” (6). A premature baby has a higher risk of having cerebral palsy, despite whether or not it came from a multiple birth. It was also shown in the Australian study that “the observed rate of cerebral palsy in infants of low or very low birth weight was not different from that in singletons and twins of the same weight” (6). Whether or not it came from a multiple birth, any premature infant has a significantly higher risk than one carried to term. “Preterm birth is associated with a clear increase of cerebral palsy. During the 1980’s, there was an increase in the survival of very preterm babies which was accompanied by a sharp increase in the rate of cerebral palsy in this group” (5). Through multiple birthing, birth complications, or early delivery, several common causes of premature birth, if a baby is born premature, it has a notably higher chance of being born with cerebral palsy.
Babies in multiple births are in clearly higher numbers of the population with cerebral palsy. Because infants in multiple births are much more likely to be born prematurely, and premature babies are the most susceptible to be born with cerebral palsy, infants in multiple births have much higher chances of being born with cerebral palsy. “Studies of large groups of children with cerebral palsy have noted an excess of twins. Although twins account approximately for 2% of the population, they account for 10% of all cases of cerebral palsy” (4). A population report from 1956-1985 observed a prevalence of cerebral palsy in twins 2.6 times that in singletons and found it suggestive that triplets were at a higher risk (6). In the Australian study, twins were 4.6 times more likely to have cerebral palsy than singletons, and triplets were 17 times more likely. Triplet pregnancies produced a child with cerebral palsy 47 times more often than singleton pregnancies. Triplet gestations, however, were uncommon, and twins accounted for 86% of cerebral palsy among multiple births (6). These numbers show that multiple pregnancies possess a much greater probability of producing children with cerebral palsy.
Through the use of fertilization techniques, multiple births have increased in numbers in the past 30 years. The average 5-year increase from 1960-1989 in the Australian study was 3.9% for twins and 67% for triplets. “This has contributed to a significant annual increase in the proportion of multiple births associated with cases of cerebral palsy” (6). Before 1970, 5.3 % of all cerebral palsy was in multiple births, in 1980, 6.6%, and in 1990, 10.3% (6).
Multiple births are much more common now than in the past. Multiple pregnancies are fairly easy to identify as high-risk pregnancies for cerebral palsy. Because of the high susceptibility infants in multiple births have towards cerebral palsy, the trend of fertilization drugs needs to be carefully examined. There are several documentations about the risks that multiple pregnancies pose to the outcomes of cerebral palsy in the babies, and this is ground for concern for parents, children, and doctors.
Bibliography
Literature Cited
1) Petterson, B.; Blair, E.; Watson, L.; Stanely, F. Adverse outcome after multiple pregnancies. Baillierres Clinical Obstetrics & Gynecology. 12(1): 1-17; 1998
2) Gaffney, G.; Johnson, A. Cerebral palsy and neonatal encephalopathy. British Medical Journal. 308(6942): 1507-1514; 1994
3) Alan, W.; Dranfield, D.; Kessler, D. Cerebral palsy in preterm infants. The Lancet. 343(8904): 1048-1062; 1994
4) Perlman, J.; Burns, D.; Twickler, D.; Weinberg, A. Fetal hypokinesia syndrome in the monochorionic pair of a triplet pregnancy secondary to severe disruptive cerebral injury. American Academy of Pediatrics. 96(3): 521-523; 1995
5) Murphy, D.; Hope, P. Johnson, A. Neonatal risk factors for cerebral palsy in very preterm babies: case control study. British Medical Journal. 314(7078): 404-408; 1997
6) Petterson, B.; Nelson, K.; Watson, L.; Stanley, F. Twins, triplets, and cerebral palsy in births in western Australia in the 1980’s. British Medical Journal. 307(6914): 1239-1243; 1993
7) American Cerebral Palsy Association. What is cerebral palsy? 1999. http://www.cerebralpalsy.org/whatis.html
Literature Cited
1) Petterson, B.; Blair, E.; Watson, L.; Stanely, F. Adverse outcome after multiple pregnancies. Baillierres Clinical Obstetrics & Gynecology. 12(1): 1-17; 1998
2) Gaffney, G.; Johnson, A. Cerebral palsy and neonatal encephalopathy. British Medical Journal. 308(6942): 1507-1514; 1994
3) Alan, W.; Dranfield, D.; Kessler, D. Cerebral palsy in preterm infants. The Lancet. 343(8904): 1048-1062; 1994
4) Perlman, J.; Burns, D.; Twickler, D.; Weinberg, A. Fetal hypokinesia syndrome in the monochorionic pair of a triplet pregnancy secondary to severe disruptive cerebral injury. American Academy of Pediatrics. 96(3): 521-523; 1995
5) Murphy, D.; Hope, P. Johnson, A. Neonatal risk factors for cerebral palsy in very preterm babies: case control study. British Medical Journal. 314(7078): 404-408; 1997
6) Petterson, B.; Nelson, K.; Watson, L.; Stanley, F. Twins, triplets, and cerebral palsy in births in western Australia in the 1980’s. British Medical Journal. 307(6914): 1239-1243; 1993
7) American Cerebral Palsy Association. What is cerebral palsy? 1999. http://www.cerebralpalsy.org/whatis.html