The odds of a twin having twins depends on whether the twin is identical (from single fertilized egg that divided) or fraternal (more than one egg, fertilized by different sperm) According to Montreal Children's Hospital geneticisit, Dr. Laura Rusell, identical twins do not appear to have an increased chance of giving birth to twins.
Female fraternal twins, however, have a 1 in 58 chance of giving birth to fraternal twins. Lending credence to the importance of genetic factors in fraternal twinning. These figures are the same as those for the sisters or offspring of female fraternal twins.
Male fraternal twins also have an increased chance,1 to 116 cchances of having fraternal twins.
Many factors can affect twinning including the mother's age, use of fertility drugs, and even her height and weight. The rate of birthing identical twins appears to be the same thoughout the world, occuring in 1 out of every 250 pregnancies. The rate of fraternal twin births, however, varies geography; "6 in 1,000 for Europians and North American CVaucasina, 1 to 100 for Nigerian blacks" . (Source- RD December2007)
Female fraternal twins, however, have a 1 in 58 chance of giving birth to fraternal twins. Lending credence to the importance of genetic factors in fraternal twinning. These figures are the same as those for the sisters or offspring of female fraternal twins.
Male fraternal twins also have an increased chance,1 to 116 cchances of having fraternal twins.
Many factors can affect twinning including the mother's age, use of fertility drugs, and even her height and weight. The rate of birthing identical twins appears to be the same thoughout the world, occuring in 1 out of every 250 pregnancies. The rate of fraternal twin births, however, varies geography; "6 in 1,000 for Europians and North American CVaucasina, 1 to 100 for Nigerian blacks" . (Source- RD December2007)
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