Multiple Births
When bearing a child there may be a possibility of having more than just one child, which is referred to as a multiple birth. A multiple birth is one in which two or more fetuses develop at one time in the uterus. This happens when a woman naturally releases more than one egg from her ovaries. Most multiple births are caused from using fertility drugs.
The most common types of multiple births are twins. Twins are categorized into different groups. The two most common types of twins are fraternal and identical.
Fraternal twins are a result of two eggs and two sperm (Segal 4). Twins can be conceived at different times when there are two separate sperm. The tendency to conceive fraternal twins seems to be heredity. Some studies show higher incidence where there is a history of twins on the mother’s side of the family. Fraternal twins can be boy/girl, girl/girl, or boy/boy. Opposite sex twins make up one-third of the twin population, about one in 240 births (Wolner 32). Boy/girl twins develop as differently as single birth children from the time of conception. Fraternal twins can be conceived at the same time, but their birthdays can be days, weeks or even months apart (Segal 37).
The second most common type of twins is identical twins. Chances of having identical twins are one in two hundred births (Vaughan 12). Identical twins happen when a single fertilized egg splits usually one to fourteen days after conception (Segal 6). Identical twins are genetically alike. They have the same chromosomes and usually have a lot of the same physical features. They always have the same blood type, hair, eye color, nose, ears, and lip shapes
Almost one quarter of identical twins are mirror twins. This means that the twins will appear to be reflections of one another (Wolner 102). One twin will be right-handed and the other will be left-handed. Internal organs and skeletal features will be on the opposite sides of the body. Their hair whorls will turn in opposite directions. Mirror twins are identical twins that scientists believe split later in the embryonic stage (Wolner 103). When the cluster of cells do finally spit, there is already a formed right side and formed left side with one twin developing from each side. There are even medical examples where one mirror image twin has internal organs on the right side of the body and the other on the left (Wolner 104).
Multiple gestation is a medical term that refers to a women who is pregnant with twins, triplets, or other higher- order multiple pregnancies (Segal 97). This will occur in slightly less than two percent of all pregnancies (Segal 97). Within the category of multiple gestation, twin births are by far the most common, accounting for ninety-five percent of all multiple pregnancies.
Triplets are a unique type of multiple births. Triplets are born at the same time of the same mother. One set of triplets is born about every 9,216 births (Vaughan16). Fraternal triplets are born from three egg cells. Identical triplets are born from one egg cell that divided into three separate eggs. Triplets may also include an identical pair plus a third fraternal.
Quadruplets are four children born to a mother at one time. They occur more often than quintuplets, but less often then triplets. Quadruplets are born once in every 884,763 births (Wright 19). Identical quadruplets are born from the cell mass of a single egg that became separated. There are also four possible combinations of identical and fraternal quadruplets. That happens when some are in one cell mass and the other one or two have their own separate cell mass. There are also fraternal quadruplets that have their own egg cell.
Quintuplets are five babies born to the same mother at one time. They are estimated to occur once in every eighty-five million natural births (Wright 26). It is very common for all of them not to survive.
In history, there has been as many as fifteen babies conceived during pregnancy, one thirty-five year old women had quindecaplets removed from her womb. It was known that the babies would not have a chance of survival. There are many reported births of sexuplets (6), septuplets (7), octuplets (8), nonuplets (9), decaplets (10), undecaplets (11), duodecaplets (12), tridecaplets(13), Quadecaplets (14), and quindecaplets. The highest number of surviving babies is octuplets (Rugh 22).
One of the rare types of twins is a conjoined twin, also called Siamese twins. Siamese is a term made famous from Chang and Eng born in 1811 in Siam (Rugh 65). It is estimated that conjoined twins occur one in 50,000 to one in 100, 000 births (Segal 29). They are joined at identical sites. Conjoined twins originate from a single fertilized egg. The developing embryo starts to split into identical twins within the first two weeks after conception. However, the process stops before it is complete, leaving a partially separated egg that develops into a conjoined fetus. Among those deliveries, forty to sixty percent are stillborn and thirty-five survive only one day (Segal 297). The overall survival rate of conjoined twins are between five and twenty-five percent (Segal 30). If the twins have separate sets of organs, chances for surgery and survival are greater than if they share the same organs.
Conjoined twinning is unaffected by maternal age, ethnicity, and number of previous children. Family history of conjoined twinning is also unrelated to producing conjoined twins; so genetic factors are not involved.
Conjoined twins born today are detected during routine prenatal examination including sonograms. However, before sonograms were available only fifty to seventy percent of conjoined twins were identified before birth (Segal 301). A first diagnosed conjoined twin was in 1976 at thirty-seven weeks (Segal 302). Conjoined twins have been diagnosed as early as nine weeks.
Parents and physicians struggle over whether or not to separate conjoined twins. Separation was first attempted in the tenth century on the first recorded conjoined pair in history (Segal 304). Nearly two hundred surgical separations of conjoined twins have been attempted with approximately ninety percent occurring after 1950 (Segal 306). Seventy-three percent of conjoined twins are connected at mid torso, twenty-three percent at lower torso, and four percent at the upper torso (Segal 306). Survival of one or both twins has occurred in close to 150 cases.
When separating conjoined twins, operations are generally delayed until twins reach six to twelve months of age to improve their trauma tolerance and to avoid newborn care complexities. The extra time required is also critical for allowing the twins skin to expand.
The most unique form of twin births is called heteropaternal superfecundation. This occurs when an egg is released, even though another egg has been fertilized (Wright 96). If another man’s sperm fertilizes the second egg, the fetuses would be no closer genetically than half siblings.
Multiple births can be risky. A women’s uterus is only capable of carrying, feeding, and providing oxygen for a certain amount of fetuses. Twins are more susceptible to birth defects, spontaneous mutations, and vascular problems that threaten early life (Wright 89). Simply being a twin is stressful and raises the odds against survival because of the competition for space and nutrients. If an embryo disappears in the first trimester it has probably been absorbed by the placenta or by the other twin with little or no evidence that it ever existed, except for the tiny image left on ultrasound (Segal 87). A careful examination of the placenta after birth will sometimes reveal a nodule that turns out to be the remains of a vanished twin. The death of one twin poses a real threat to the other. Identical twins share the same circulation in the womb, and the death of one could cause a blood clot to pass into the survivor, causing heart damage (Wright 96).
When having multiple births your children may be premature, have low birth weights, respiratory difficulties, and learning disabilities. One-third of all twins will be delivered premature ( Vaughan 120). The greater number of fetuses increases the weight and volume, which causes strain on the mother’s cervix. Pressure on the cervix is stronger leading premature labor. When children are born early their birth weights are lower. The average birth weight of a child is about 7 pounds, 5 pounds for twins, and 3 pounds for triplets (Vaughan 127). Babies who are born very prematurely are also more likely to have complications that can lead to long-term problems. The babies may have problems in functioning of their lungs, heart, brain, mental retardation, seizure disorders, vision problems, hearing loss, and kidney problems. A premature baby is more likely to die than one who is born at full-term. Twins and triplets are at much greater risk for health problems than single births. Twins are five times more likely to die in the first year as in single births, and triples on up are ten times more likely to die in the first year too (Segal 99). In 1993 the Office for National Statistics recorded that triplets were about six times more likely to die than single births in the first year of their lives.
Not only are the babies in trouble when being a multiple but the mother is in great danger also. Mothers have a risk of anemia, high blood pressure, and convulsions during pregnancy. They also suffer from emotional problems. The mother has to worry about feeding and caring for more than one child.
To reduce the risks, doctors try to get mothers to have babies one at a time, but that is not possible in all cases. In some multiple pregnancies, doctors may recommend that some of the embryos be aborted. The others have more of a chance of survival, because they have more space to develop.
When women have trouble getting pregnant they resort to fertility drugs, such as Clomid, Pergonal, Humegon, Repronex, Gonal F, and Follistim. A women’s ovary uses only 400 eggs out of the half-million she has available. Surplus eggs are released into the fallopian tubes, leading to twin conception in about ten percent of the women who take fertility drugs such as clomiphene citrate. Pergonal, another powerful drug that helps the egg mature, causes twins in about twenty-five percent of the pregnancies. In vitro fertilization and other new technology require taking eggs from the ovary and mixing them with sperm in a petri dish. When the eggs are fertilized, they are placed in the uterus or fallopian tube. Typically more than one egg is implanted, so the chances of multiple births are quite high.
For the one out of five couples who have not needed contraceptives because the seemed to be sterile, there are antisterility pills. These pills, which are really hormone additives, not only help many women to overcome some kinds of biological sterility but also seem to increase the likelihood of multiple births. Some sterile women, treated with these ovulations-stimulating hormones, have born twins, triplets, or even quadruplets.
Older women are more likely to give birth to multiples naturally, but they also have more trouble conceiving and therefore they turn to fertility drugs. Multiple births are one-third due to older women and two-thirds due to fertility drugs. Fifteen percent of pregnancies resulting multiple births are due to fertility drugs compared to one percent naturally (Rugh 12).
Multiple births occur when doctors prescribe strong fertility drugs that stimulate
the growth of follicles, sacks of fluid that each contain one egg until they grow to an inch
in size. Under normal circumstances, a woman’s body regulates the process and only
allows one follicle to release its egg. In women who take fertility drugs because they
do not ovulate properly; the ovaries are supercharged by the drugs. This can prompt as
many as 40 follicles to mature. And in some women who are sensitive to the drugs, up to
a dozen eggs may be released all at once. A dozen eggs can become a dozen babies.
To avoid multiple conceptions, fertility experts are supposed to carefully monitor the
follicles daily with the use of an ultrasound scan to accurately determine how many are maturing at once.
Identical twins spend a lot of time together and are usually each other’s best friend. Although they like other people, their twin is the person they usually choose to be with, especially when they are young. They do not like to be apart. Identical twins usually have their own private language and have the ability to do the same in the same activities. They also enjoy each other’s company because the usually have the same interest. Identical twins usually care for one another more deeply than fraternal twins. This is because of the special bond between them that grew while they were inside their mother. After age nine or ten, identical twins usually choose to form their own identities.
Identical twins that were reared apart were actually somewhat more alike in their attitudes than identical twins reared together (Wright 147). Various tests of ability show extremely high levels of heredity; whether raised apart or together, identical twins scored almost as alike as the same person tested twice (Wright 147). Identical twins reared apart are more likely to be similar in personality, temperament, occupational interests, leisure-time interests, and social attitudes as identical twins raised together. This leads to believe that the similarities between twins are due to genes, not the environment. Environment does play a substantial role in the formation of individual personalities. “Family influences show clearly in attitudes, values, choice of mate, and in presence of nonpsychotic psychiatric symptomatology. The cultural or regional influences transmitted by the family and social network also are present and probably show in general personality traits ranging from emotional expressivity to drinking habits… everything in these data points toward the massive and perhaps predominant influences of family and culture on attitudes and psychological traits” (Wright 70).
Early in a Minnesota study, the ending results indicated that separated twins were sometimes more similar than twins raised together. “ You could argue that the twins reared together, because of the presence of each other, forced themselves apart. They wanted to differentiate. Whereas, if they were reared apart, they couldn’t care less about this” (Wright 70).
The Minnesota project studies the physical, mental, and social changes that occur in twins as they pass from childhood into adolescence and from adolescence into young adulthood.
University of Minnesota researchers, led by psychologist Bouchard, found that seventy percent of the intelligence is accounted for by genes, the strongest correlation found for any characteristic. Genetics also accounts for about fifty percent of personality differences, including traits such as extroversion, fifty percent of religiosity, including how often someone attends religious events, and about forty percent for job interest. Environment accounts for the rest of the differences, but the researchers note that even two children in the same family many not share the same environment (Wright 70).
The study has been widely profiled in the news media because of the eerie similarities that have been observed in reunited twins. For example, two twins were reunited at the age of thirty with similar mustaches hairstyles, glasses, big belt buckles, and key rings. Each twin was a volunteer firefighter and made their living installing safety equipment. Each also drank Budweiser and crushed the cans when finished.
The statistics have shown that on average, identical twins tend to be around eighty percent the same in everything from stature, to health, to IQ to political views (Wright 84). The similarities are partly the product of similar upbringing. The evidence from the comparison of twins raised apart points rather convincingly to genes as the source of a lot of that likeness. In the most widely publicized study of this type, launched in 1979, University of Minnesota psychologist Bouchard and his colleagues have chronicled the fates of about sixty percent of identical twins raised separately (Segal 86). Some of the pairs had scarcely met before Bouchard contacted them, and yet the behaviors and personalities and social attitudes they displayed were often remarkably alike.
Identical twins become less similar in terms of physical traits like looks and weight over time. However, they become more similar in abilities such as vocabularies and arithmetic scores. As fraternal twins get older, they leave their home, marry, start careers, families, and develop their own circle of friends. They become less similar with respect to vocabularies and arithmetic scores.
Identical twins tend to have more similar ages at the time of death than fraternal twins do. That is, identical twins are more likely to die at about the same age, and fraternal twins are more likely to die at different ages.
In summary, there are many risks to any pregnancy, but the risks during multiple births are great. Researchers have found that premature birth is more common amoung multiple birth pregnancies. The thought of having more than one child at a time is unbelievable. Hospitals are becoming more equipped to handle these types of situations. This new technology gives more hope to successful multiple and premature births.
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