Twins natural book-The Creativity Post | Twins Reared Apart: The Best Natural Experiment

After the shock and disbelief sinks in that you really are cooking more than one bun, you do everything you can to learn about your crazy new reality. If you are a first time Mom, get one of the old standbys covering all aspects of a pregnancy and delivery. They will answer tons of questions and alert you to new and fun things your body will start doing! A journal can help you remember everything as your mind slowly slips away into pregnancy. It has separate sections to document all the ultrasounds, doctor appointments, and a space for a daily journal to remember all those fun and ridiculous pregnancy moments.

Twins natural book

If more women did, experts say, it would save hundreds of millions of dollars a Skinny puppy neuwerld and untold heartache Twins natural book families. So if even informed women like Julie have what Stillman calls "some level of denial," what to do? Safe sleep Find out how to keep baby safe in their own bed. On arrival at hospital the mother will be checked over by her midwife and the well being of the babies will be monitored, usually by a cardiotocograph, or CTG. Share your thoughts with other customers. Treatments for infertility This infertility article describes the most common treatments for infertility and explains what each treatment involves for parents to be. It generally is recommended that women who are pregnant with multiples gain more weight than women who are pregnant with one fetus. Return to Book Page. So I was on bed Twins natural book for 10 weeks.

Transgender gown plus size. Twins and other multiples

Retrieved 28 February This form had been speculated until only recently being recorded in Western medicine. Sunderland, Mass: Sinauer Associates. Identical twins do not have the same fingerprints however, natuural even within the confines of the womb, the Male bodybuilder porn touch different parts of their environment, giving rise to small variations in their corresponding prints and Twisn making them unique. Learn more about Amazon Prime. Michelle Zink Twins natural book Author. Associated Press. The vast majority of twins are either dizygotic fraternal or monozygotic identical. Twins natural book such pairing was born in London in to a white mother and Caribbean father. Intrauterine death occurs bokk a baby dies during late pregnancy. The Sun. This occurs when the zygote starts to split after day 12 [40] following fertilization and fails to separate completely. Rayburn November

Twins reared apart allow new insights into nature and nurture.

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Twins reared apart allow new insights into nature and nurture. I was very privileged to have spent my first post-doctoral years associated with the Minnesota study of Twins Reared Apart, directed by University of Minnesota professor Thomas J. Bouchard, Jr. Meeting the twins and observing their behaviors over the course of a week was a thrilling experience. And watching their relationships with one another evolve was also exciting. Most of the twins were adoptees and were so gratified to finally meet a biological family member, especially a twin.

The book includes marvelous pictures of some of the twins we studied, as well as the amazing life history events responsible for their separation and eventual reunion. The reared apart twin design provides one of the best approaches to studying genetic and environmental influence on behaviors involves the rare pairs of identical and fraternal twins reared apart and reunited.

The size of the correlation between reared apart identical co-twins offer scientists a pure estimate of genetic influence on behavioral and physical traits. The size of the correlation between reared apart fraternal co-twins provides an informative comparison.

Greater resemblance between identical than fraternal twins is consistent with genetic influence on the traits under study. The Minnesota study began in and continued for twenty years. The volume of material that accumulated was too vast to include in a single volume. Information about my other books can also be found there. It is amazing that twins continue to be separated today, given the increased appreciation for family ties.

In the past, twins were separated mostly due to illegitimacy or maternal death. Today, the new assisted reproductive technologies that may yield several babies, not just one, have caused some families to relinquish one or more of their multiple birth children; these families may lack the resources to properly care for them.

In fact, I am studying those twins, as well. And new cases occasionally cross my desk from unexpected sources. These cases are all scientifically informative in their own way, but bringing the twins together is the most satisfying part of the process.

Cook Goodreads Author 4. Monozygotic twinning occurs in birthing at a rate of about 3 in every deliveries worldwide about 0. East of Eden by John Steinbeck 4. Effect of diet and heredity on the human twinning rate". This occurrence is similar to the vanishing twin syndrome, but typically occurs later, as the twin is not reabsorbed. Elswyth Thane.

Twins natural book

Twins natural book

Twins natural book

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Imbreathing books 0 friends. Mir books friends. Kathryn books friends. Themis-Athena Lioness at Large books friends. Bettie books friends. Susanna - Censored by GoodReads books friends. Dec 15, AM. The Poet by Micheal Connelly. The fact that crime reporter Jack McEvoy is so passionate about solving his brothers murder case is touching. I'm also an identical twin,so I can relate. Aug 24, PM. Actually, Stephen King's "The Shining" does not have any twins.

That only happens in the film version of the book. Feb 26, PM. I don't believe the girls in Levine's Two Princesses of Bamarre are twins. I think Meryl is older. Jul 02, PM. What about "The ground beneath her feet"? Oct 01, PM. Feb 03, PM. Elena wrote: "how is Gone Girl about twins???? Feb 13, AM. Throne of Jade had twins in it? Mar 29, AM. Jun 26, PM. Add a reference: Book Author. Search for a book to add a reference. We take abuse seriously in our discussion boards.

Dizygotic twins, like any other siblings, will practically always have different sequences on each chromosome, due to chromosomal crossover during meiosis. Like any other siblings , dizygotic twins may look similar, particularly given that they are the same age. However, dizygotic twins may also look very different from each other for example, be of opposite sexes. Studies show that there is a genetic proclivity for dizygotic twinning. However, it is only the mother who has any effect on the chances of having such twins; there is no known mechanism for a father to cause the release of more than one ovum.

Dizygotic twinning ranges from six per thousand births in Japan similar to the rate of monozygotic twins to 14 and more per thousand in some African countries. Dizygotic twins are also more common for older mothers, with twinning rates doubling in mothers over the age of Monozygotic MZ or identical twins occur when a single egg is fertilized to form one zygote hence, "monozygotic" which then divides into two separate embryos. Regarding spontaneous or natural monozygotic twinning, a recent theory proposes that monozygotic twins are probably formed when a blastocyst contains two inner cell masses ICM , each of which will lead to a separate fetus, rather than by the embryo splitting while hatching from the zona pellucida the gelatinous protective coating around the blastocyst.

Monozygotic twins may also be created artificially by embryo splitting. It can be used as an expansion of in vitro fertilization IVF to increase the number of available embryos for embryo transfer. Monozygotic twinning occurs in birthing at a rate of about 3 in every deliveries worldwide about 0. The likelihood of a single fertilization resulting in monozygotic twins is uniformly distributed in all populations around the world.

IVF techniques are more likely to create dizygotic twins. For IVF deliveries, there are nearly 21 pairs of twins for every 1, Monozygotic twins are genetically nearly identical and they are always the same sex unless there has been a mutation during development. The children of monozygotic twins test genetically as half-siblings or full siblings, if a pair of monozygotic twins reproduces with another pair or with the same person , rather than first cousins.

Identical twins do not have the same fingerprints however, because even within the confines of the womb, the fetuses touch different parts of their environment, giving rise to small variations in their corresponding prints and thus making them unique. Monozygotic twins always have the same phenotype. Normally due to an environmental factor or the deactivation of different X chromosomes in female monozygotic twins, and in some extremely rare cases, due to aneuploidy , twins may express different sexual phenotypes , normally from an XXY Klinefelter syndrome zygote splitting unevenly.

Monozygotic twins, although genetically very similar, are not genetically exactly the same. The DNA in white blood cells of 66 pairs of monozygotic twins was analyzed for , single-nucleotide polymorphisms known to occur in human populations.

If they occur early in fetal development, they will be present in a very large proportion of body cells. Another cause of difference between monozygotic twins is epigenetic modification , caused by differing environmental influences throughout their lives. Epigenetics refers to the level of activity of any particular gene. A gene may become switched on, switched off, or could become partially switched on or off in an individual.

This epigenetic modification is triggered by environmental events. Monozygotic twins can have markedly different epigenetic profiles. A study of 80 pairs of monozygotic twins ranging in age from three to 74 showed that the youngest twins have relatively few epigenetic differences. The number of epigenetic differences increases with age. Fifty-year-old twins had over three times the epigenetic difference of three-year-old twins.

Twins who had spent their lives apart such as those adopted by two different sets of parents at birth had the greatest difference. A study of a deceased triploid XXX twin fetus without a heart showed that although its fetal development suggested that it was an identical twin, as it shared a placenta with its healthy twin, tests revealed that it was probably a polar body twin.

The authors were unable to predict whether a healthy fetus could result from a polar body twinning. In , a study argued that many cases of triploidy arise from sesquizygotic semi-identical twinning.

See Semi-identical Twins below, under Unusual twinnings. The degree of separation of the twins in utero depends on if and when they split into two zygotes. Dizygotic twins were always two zygotes. Monozygotic twins split into two zygotes at some time very early in the pregnancy. The timing of this separation determines the chorionicity the number of placentae and amniocity the number of sacs of the pregnancy.

Dichorionic twins either never divided i. Monoamnionic twins divide after the first week. In very rare cases, twins become conjoined twins. Non-conjoined monozygotic twins form up to day 14 of embryonic development, but when twinning occurs after 14 days, the twins will likely be conjoined. It is a common misconception that two placentas means twins are dizygotic.

But if monozygotic twins separate early enough, the arrangement of sacs and placentas in utero is indistinguishable from dizygotic twins. DiDi twins have the lowest mortality risk at about 9 percent, although that is still significantly higher than that of singletons.

Monochorionic twins share the same placenta , and thus have a risk of twin-to-twin transfusion syndrome. Monoamniotic twins are always monozygotic. Monoamniotic twins, as with diamniotic monochorionic twins, have a risk of twin-to-twin transfusion syndrome. Also, the two umbilical cords have an increased chance of being tangled around the babies.

Because of this, there is an increased chance that the newborns may be miscarried or suffer from cerebral palsy due to lack of oxygen. Mortality is highest for conjoined twins due to the many complications resulting from shared organs. Dichorionic-diamniotic twins at 8 weeks and 5 days since co-incubation as part of IVF.

The twin at left in the image is shown in the sagittal plane with the head pointing towards upper left. The twin at right in the image is shown in the coronal plane with the head pointing rightwards.

Abdominal ultrasonography of monoamniotic twins at a gestational age of 15 weeks. There is no sign of any membrane between the fetuses. A coronal plane is shown of the twin at left, and a sagittal plane of parts of the upper thorax and head is shown of the twin at right. A study has found that insulin-like growth factor present in dairy products may increase the chance of dizygotic twinning. Specifically, the study found that vegan mothers who exclude dairy from their diets are one-fifth as likely to have twins as vegetarian or omnivore mothers, and concluded that "Genotypes favoring elevated IGF and diets including dairy products, especially in areas where growth hormone is given to cattle, appear to enhance the chances of multiple pregnancies due to ovarian stimulation.

It may also be linked to the increase of growth hormones in food. About 1 in 90 human births 1. The widespread use of fertility drugs causing hyperovulation stimulated release of multiple eggs by the mother has caused what some call an "epidemic of multiple births ". Nevertheless, the rate of monozygotic twins remains at about 1 in across the globe. In a study on the maternity records of Hausa women living in the Savannah zone of Nigeria , there were 40 twins and 2 triplets per births.

Twenty-six percent of twins were monozygotic. The incidence of multiple births, which was about five times higher than that observed in any western population, was significantly lower than that of other ethnic groups, who live in the hot and humid climate of the southern part of the country.

The incidence of multiple births was related to maternal age but did not bear any association to the climate or prevalence of malaria.

Twins are more common in African Americans. Dizygotic twin pregnancies are slightly more likely when the following factors are present in the woman:.

Women undergoing certain fertility treatments may have a greater chance of dizygotic multiple births. The risk of twin birth can vary depending on what types of fertility treatments are used. With in vitro fertilisation IVF , this is primarily due to the insertion of multiple embryos into the uterus.

Ovarian hyperstimulation without IVF has a very high risk of multiple birth. Reversal of anovulation with clomifene trade names including Clomid has a relatively less but yet significant risk of multiple pregnancy. A year German study [62] of 8, vaginally delivered twins that is, 4, pregnancies in Hesse yielded a mean delivery time interval of The study stated that the occurrence of complications "was found to be more likely with increasing twin-to-twin delivery time interval" and suggested that the interval be kept short, though it noted that the study did not examine causes of complications and did not control for factors such as the level of experience of the obstetrician, the wish of the women giving birth, or the "management strategies" of the procedure of delivering the second twin.

There have also been cases in which twins are born a number of days apart. Possibly the worldwide record for the duration of the time gap between the first and the second delivery was the birth of twins 97 days apart in Cologne, Germany, the first of which was born on November 17, Researchers suspect that as many as 1 in 8 pregnancies start out as multiples, but only a single fetus is brought to full term, because the other fetus has died very early in the pregnancy and has not been detected or recorded.

There are several reasons for the "vanishing" fetus, including it being embodied or absorbed by the other fetus, placenta or the mother. This is known as vanishing twin syndrome. Also, in an unknown proportion of cases, two zygotes may fuse soon after fertilization, resulting in a single chimeric embryo, and, later, fetus. Conjoined twins or the once-commonly used term "siamese" are monozygotic twins whose bodies are joined together during pregnancy.

This occurs when the zygote starts to split after day 12 [40] following fertilization and fails to separate completely. This condition occurs in about 1 in 50, human pregnancies.

Most conjoined twins are now evaluated for surgery to attempt to separate them into separate functional bodies. The degree of difficulty rises if a vital organ or structure is shared between twins, such as the brain , heart or liver. A chimera is an ordinary person or animal except that some of their parts actually came from their twin or from the mother. A chimera may arise either from monozygotic twin fetuses where it would be impossible to detect , or from dizygotic fetuses, which can be identified by chromosomal comparisons from various parts of the body.

The number of cells derived from each fetus can vary from one part of the body to another, and often leads to characteristic mosaicism skin coloration in human chimeras. A chimera may be intersex , composed of cells from a male twin and a female twin. In one case DNA tests determined that a woman, mystifyingly, was not the mother of two of her three children; she was found to be a chimera, and the two children were conceived from eggs derived from cells of their mother's twin.

Sometimes one twin fetus will fail to develop completely and continue to cause problems for its surviving twin. One fetus acts as a parasite towards the other. Sometimes the parasitic twin becomes an almost indistinguishable part of the other, and sometimes this needs to be treated medically.

A very rare type of parasitic twinning is one where a single viable twin is endangered when the other zygote becomes cancerous, or "molar". This means that the molar zygote's cellular division continues unchecked, resulting in a cancerous growth that overtakes the viable fetus.

Typically, this results when one twin has either triploidy or complete paternal uniparental disomy , resulting in little or no fetus and a cancerous, overgrown placenta, resembling a bunch of grapes.

Occasionally, a woman will suffer a miscarriage early in pregnancy, yet the pregnancy will continue; one twin was miscarried but the other was able to be carried to term. This occurrence is similar to the vanishing twin syndrome, but typically occurs later, as the twin is not reabsorbed.

It is very common for twins to be born at a low birth weight. More than half of twins are born weighing less than 5. Premature birth and low birth weights, especially when under 3. Monozygotic twins who share a placenta can develop twin-to-twin transfusion syndrome. This condition means that blood from one twin is being diverted into the other twin.

One twin, the 'donor' twin, is small and anemic , the other, the 'recipient' twin, is large and polycythemic. The lives of both twins are endangered by this condition. Stillbirths occurs when a fetus dies after 20 weeks of gestation. There are two types of stillbirth, including intrauterine death and intrapartum death.

Intrauterine death occurs when a baby dies during late pregnancy. Intrapartum death, which is more common, occurs when a baby dies while the mother is giving birth. The cause of stillbirth is often unknown, but the rate of babies who are stillborn is higher in twins and multiple births. Caesareans or inductions are advised after 38 weeks of pregnancy for twins, because the risk of stillbirth increases after this time. For otherwise healthy twin pregnancies where both twins are head down a trial of vaginal delivery is recommended at between 37 and 38 weeks.

Twin studies are utilized in an attempt to determine how much of a particular trait is attributable to either genetics or environmental influence. These studies compare monozygotic and dizygotic twins for medical , genetic , or psychological characteristics to try to isolate genetic influence from epigenetic and environmental influence.

Twins that have been separated early in life and raised in separate households are especially sought-after for these studies, which have been used widely in the exploration of human nature. Classical twin studies are now being supplemented with molecular genetic studies which identify individual genes. Among dizygotic twins, in rare cases, the eggs are fertilized at different times with two or more acts of sexual intercourse, either within one menstrual cycle superfecundation or, even more rarely, later on in the pregnancy superfetation.

This can lead to the possibility of a woman carrying fraternal twins with different fathers that is, half-siblings. This phenomenon is known as heteropaternal superfecundation. One study estimates that the frequency of heteropaternal superfecundation among dizygotic twins, whose parents were involved in paternity suits, was approximately 2.

Dizygotic twins from biracial couples can sometimes be mixed twins , which exhibit differing ethnic and racial features. One such pairing was born in London in to a white mother and Caribbean father. Heterotopic pregnancy is an exceedingly rare type of dizygotic twinning in which one twin implants in the uterus as normal and the other remains in the fallopian tube as an ectopic pregnancy. Ectopic pregnancies must be resolved because they can be life-threatening to the mother.

However, in most cases, the intrauterine pregnancy can be salvaged. Among monozygotic twins, in extremely rare cases, twins have been born with different sexes one male, one female. The probability of this is so small that multiples having different sexes is universally accepted as a sound basis for in utero clinical determination that the multiples are not monozygotic. Another abnormality that can result in monozygotic twins of different sexes is if the egg is fertilized by a male sperm but during cell division only the X chromosome is duplicated.

This results in one normal male XY and one female with Turner syndrome 45,X. Monozygotic twins can develop differently, due to their genes being differently activated. As of only two cases have been reported. Both ova are then fertilized, each by a different sperm, and the coalesced zygotes undergo further cell duplications developing as a chimeric blastomere. If this blastomere then undergoes a twinning event, two embryos will be formed, with different paternal genetic information and identical maternal genetic information.

This results in a set of twins with identical gene sequence from the mother's side, but different sequences from the father's side. Cells in each fetus carry chromosomes from either sperm, resulting in chimeras.

This form had been speculated until only recently being recorded in Western medicine. In , a study reported a case of a pair of living twins, which shared an identical set of maternal chromosomes, while each having a distinct set of paternal chromosomes, albeit from the same man, and thus they most likely share half of their father's genetic makeup. The twins were both found to be chimeras. One was an intersex XX, and one a XY male. The exact mechanism of fertilization could not be determined but the study stated that it was unlikely to be a case of polar body twinning.

A second case of sesquizygotic twins was reported in Mirror image twins result when a fertilized egg splits later in the embryonic stage than normal timing, around day 9— This type of twinning could exhibit characteristics with reversed asymmetry, such as opposite dominant handedness, dental structure, or even organs situs inversus. There is no DNA-based zygosity test that can determine if twins are indeed mirror image. There have been many studies highlighting the development of language in twins compared to single-born children.

These studies have converged on the notion that there is a greater rate of delay in language development in twins compared to their single-born counterparts. Another term to describe what some people call "twin talk" is cryptophasia where a language is developed by twins that only they can understand.

The increased focused communication between two twins may isolate them from the social environment surrounding them. Idioglossia has been found to be a rare occurrence and the attention of scientists has shifted away from this idea. However, there are researchers and scientists that say cryptophasia or idioglossia is not a rare phenomenon.

Current research is looking into the impacts of a richer social environment for these twins to stimulate their development of language. Twins are common in many mammal species, including cats , sheep , ferrets , giant pandas , dolphins , dogs , deer , marmosets , tamarins , and elephants.

A female calf that is the twin of a bull becomes partially masculinized and is known as a freemartin. From Wikipedia, the free encyclopedia. One of two offspring produced in the same pregnancy. Use with P31 on items for one twin.

Having Twins: Elizabeth Noble: Books

Jennifer Ludden. Since , the rate of twin births has jumped 70 percent, according to government statistics. Courtesy of Dan Reichmann hide caption. This story is part of an occasional series. Twins, once a rarity to marvel over, are now a common part of American culture, thanks in large part to increased use of reproductive technology. Twins are conceived naturally just 2 percent of the time; for those who get pregnant with fertility treatments the rate is more than 40 percent.

But as adorable as many of us consider twins, this dramatic rise poses serious health risks , and there are mounting efforts to curb it. I wanted to have twins,' " she says. Three of these mothers, including Bernstein, used fertility treatment.

What they acknowledge, looking back now, are the incredible risks they took in their drive to become parents — risks that posed a danger to themselves and their children. I really couldn't think past that event," says Bernstein, who struggled through many years and multiple rounds of in vitro fertilization, or IVF, trying to conceive. No, that was completely a blindside. Since , the rate of twin births has jumped 70 percent, according to the Centers for Disease Control and Prevention.

In fact, more than 3 percent of all babies born in the U. Two-thirds of this increase is due to fertility treatments, while the other third is because many more women over age 30 are having babies.

The female body normally releases one egg per month, but as women age, hormonal changes make them more prone to release two eggs. Limiting the number of embryos used in IVF would only go so far in bringing down the twins rate, as many or more multiples result from other kinds of fertility treatment, such as intrauterine insemination, that are not so easily controlled.

What if far more women avoided having twins by using only one embryo in in vitro fertilization? That's what Dr. Maurizio Macaluso, who until recently headed the CDC's fertility branch, asked an economist to consider. The CDC and Aetna insurance are working to educate patients and promote this "single embryo transfer. Yet the downfalls are well-documented. The human uterus is designed to carry one baby.

When it's stuffed with two, any number of things can go wrong, and odds are good that the babies will be born prematurely. So I was on bed rest for 10 weeks. One weighed less than 2 pounds. All that, plus her C-section, plus the time her premature twins spent in neonatal intensive care six weeks for one, nine weeks for the other , also added up to some unbelievably big bills. Collura advocates for patients, and lobbies insurance companies and employers to cover fertility treatments, so she admits to feeling some responsibility for the burden twins are putting on the health care system.

To be sure, most twins end up fine. But because 60 percent are born premature, many do not survive, Collura says, and others face a lifetime of problems: developmental, cognitive, respiratory, digestive, trouble with sight and hearing. Twins are far more likely to have cerebral palsy. Pediatricians know this. OB-GYNs know this. Everybody knows this, except for the patients.

Yet it's the patients who make the crucial decisions in fertility treatment. And in the case of IVF, twins are entirely avoidable. At more than fertility clinics across the country, clinicians have become adept at choosing the most viable eggs and sperm to combine and coaxing them to produce that miraculous nugget of life, the embryo. This makes a difference when it comes to deciding how many embryos to transfer, or put into a woman's uterus.

But now, as the pregnancy rates per embryo have so increased, now you have to put far fewer. Accordingly, in recent years, guidelines set by the American Society for Reproductive Medicine have grown more conservative, and the rate of triplets and higher order multiples has plummeted. Yet the twins rate has remained stubbornly stable. But many doctors may not push that forcefully. And Stillman says those who try may have trouble convincing someone desperate to become a parent.

One big reason is money. Like anyone who gambles, patients can be seized with a sense of all or nothing. Stillman also finds an alarming shift. As more people see twins all around, patients show up at clinics thinking they'd like twins, too.

But he says they're only seeing the happy, healthy twins. It didn't even occur to me to do one," says Julie, a soft-spoken year-old single woman who spent nearly a year trying to get pregnant. She doesn't want to use her last name to protect her own privacy and that of her unborn children.

Julie was inseminated five times with donor sperm, to no avail. Then followed a failed round of IVF. By the time of her second IVF, she figured she'd never get pregnant. When her doctor said she'd have nearly the same chance with one embryo as with two, she says it just didn't make sense. So if I'd only transferred one and didn't get pregnant, I think I would have regretted not having transferred two.

Now Julie is five months pregnant with twins. She's a doctor herself, so she says she understands the risks of a twin pregnancy and prematurity. She vaguely remembers her fertility doctor talking about them. Julie's friends all said if they were in her place, they'd transfer two embryos, too.

In fact, two good friends have twins. Julie feels confident she can handle two, and she's excited about it. So, it means I won't have to do this again. Stillman says he understands all this, but it doesn't change his message: It's safer to have one baby, and using one embryo in IVF has nearly the same success rate as two.

So if even informed women like Julie have what Stillman calls "some level of denial," what to do? For one thing, punch up the message. Stillman is teaming with the advocacy group Resolve to put their warnings in a patient's voice.

Soon, every IVF patient at Shady Grove, the nation's largest fertility clinic, will be required to watch a video based on the disturbing, true story of a former patient.

Her twin girls were born at 25 weeks, and the video describes how one twin had intestinal surgery, how both spent the better part of seven months in a hospital and how impossibly difficult the whole experience was. This mother wrote her fertility doctor, asking the clinic to please share her story, so that others might think harder about the risks of twins.

Most patients must pay out of pocket, but even those covered by insurance face limits that can pressure them to take risks. So the insurance company Aetna started a new program last year.

Joanne Armstrong, Aetna's senior medical director, says women who agree to transfer just one embryo, get a two for one. That is, a free second single embryo transfer. The savings for Aetna are clear — another IVF is nothing compared with the enormous expense of premature twins. What do the mothers at the Maryland play date make of all this? Sharon Bernstein says she wouldn't trade her twin girls for anything. But she believes the push for one embryo makes sense.

If more women did, experts say, it would save hundreds of millions of dollars a year and untold heartache for families. Previous audio and Web versions of this story misidentified one of the mothers of twins. We identified a speaker as Donna Shimshi. While others in the story had undergone fertility treatment, Tyser conceived her twins naturally. Accessibility links Skip to main content Keyboard shortcuts for audio player.

Don't Tell Me! NPR Shop. Taming The Twin Trend From Fertility Treatments The rate of twin births has jumped 70 percent since , in large part because of fertility treatments. But twins pose big risks to mother and babies, and premature twins are a growing burden on the health care system.

The nation's largest fertility clinic is among those trying to curb the trend. Facebook Twitter Flipboard Email. March 29, PM ET. Heard on All Things Considered. Why More Twins? Cost to Society What if far more women avoided having twins by using only one embryo in in vitro fertilization?

Correction March 31, Previous audio and Web versions of this story misidentified one of the mothers of twins.

Twins natural book

Twins natural book