Vispirms izglītojies, kas un kā. Šoreiz Tavs viedoklis ir nepamatots. Parādi man, kur ir tā statistika, ka viņi dzimst pirms laika.Es jau paizglītojos. Kaut vai tajā pašā wikipēdijas rakstā pieminēts.
Multiple pregnancies are much less likely to carry to full term than single births, with twin pregnancies lasting only 37 weeks (3 weeks less than full term) on average
Complications during pregnancy
Vanishing twins
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 has died very early in the pregnancy and has not been detected or recorded. Early obstetric ultrasonography exams sometimes reveal an "extra" fetus, which fails to develop and instead disintegrates and vanishes. 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.
Chang and Eng Bunker, born in Siam (now Thailand) in 1811, were the origin of the term "Siamese twins".
Conjoined twins
Conjoined twins (or the 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 following fertilization and fails to separate completely. This condition occurs in about 1 in 50,000 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.
Chimerism
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; the mother was found to be a chimera and those of her cells tested happened to derive from one of the fused twins, while two of the children were derived from eggs derived from cells from the other twin making up their mother.
Parasitic twins
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.
Partial molar twins
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.
Miscarried twin
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.
Low birth weight
Twins typically suffer from the lower birth weights and greater likelihood of prematurity that is more commonly associated with the higher multiple pregnancies.
Twin-to-twin transfusion syndrome
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.
Ko tad darīt ja piesakās dvīņi? Vienu nedzemdēt, lai otram tiek viss vairāk?Tā es nerakstīju. Tikai norādīju uz iespējamajiem sarežģījumiem un negatīvajiem aspektiem.
Tas tā - zināšanai. (..) Vispirms izglītojies, kas un kā. (..) Bērni dzimst dažāda auguma, ja Tu to vēl nezināji.neesi tik butt-hurt :-P
ātrāk pie tādiem tiksi, ja tev rados ir dvīņi. precīzāk kāds no vecvecākiem ir dvīnis.
Laikam būs jāpaļaujas uz Dieva gribu
nevis divu olšūnu dvīņi, bet gan tādi, kuri izskatās katrs savādāk, bet vienalga ir dvīņiHm? Divu olšūnu dvīņi jau tieši ir tie, kas atšķirīgi. Monozigotie ir tie, kurus bieži (ne visai precīzi) dēvē par identiskajiem.
crazyzuze, man šķiet, ka viņi tieši ir 2 olšūnu dvīņi.
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