However, few genes appear to be definitively linked to hyperovulation, so it could just be that genetics in general on the mother's side contribute to the probability of having fraternal twins. Heredity on the father's side, on the other hand, does not increase a couple's odds of having twins.
However, only women ovulate. So, the mother's genes control this and the fathers don't. This is why having a background of twins in the family matters only if it is on the mother's side. And why your son's family genetics did not play a role in his twins.
Everyone has the same chance of having identical twins: about 1 in 250. Identical twins do not run in families. But there are some factors that make having non-identical twins more likely: non-identical twins are more common in some ethnic groups, with the highest rate among Nigerians and the lowest among Japanese.
The quick answer to this question is that, in a twin pregnancy, it is the mother's genes that determine twins. First up, giving birth to identical twins is not genetic, but conceiving fraternal twins is. The mother may have the genetic trait of releasing two eggs in one menstrual cycle.
The gene for hyperovulation can come from either side of the family, but the woman would need to have the gene in order for the couple to have twins based on genetics. In other words, twins on the father's side of the family will have no influence on your chances of having twins.
However, since only women ovulate, the connection is only valid on the mother's side of the family. While men can carry the gene and pass it on to their daughters, a family history of twins doesn't make them any more likely to have twins themselves.
Do twins run in the family and can twins come from the father's side? The answer is yes, Fraternal twins CAN run in the family and can come from either side. It all depends on who carries the gene for hyper-ovulation. Identical twins are a random phenomenon when a fertilized embryo splits shortly after conception.
Factors that increase the chance of twins include: consuming high amounts of dairy foods, being over the age of 30, and conceiving while breastfeeding. Many fertility drugs including Clomid, Gonal-F, and Follistim also increase the odds of a twin pregnancy.
The biological phenomenon of giving birth to twins with two different biological fathers is called heteropaternal superfecundation. This happens when a second ova released during the menstrual cycle is fertilised by sperm cells of a different man from separate sexual intercourse.
This belief is based on the assumption that twinning is genetic and runs in families. However, if that was truly the case—if there was a twin gene—then twins would occur with predictable frequency in those families that carry the gene. There is no concrete scientific evidence that suggests twins skip a generation.
Identical twins are almost always the same sex, although there are some rare exceptions to this rule. Because identical twins occur when a single fertilized egg splits and forms two embryos, each embryo has the same chromosomes (usually, XX for girls or XY for boys). Remember that sex and gender are not the same.
When people refer to Irish twins, it's important to recognize that although the siblings are close in age, they are not actually twins. In other words, they were not born during the same gestational period. Calling them Irish twins is just an informal way of classifying siblings that are born close together.
So the twins could have, in essence, skipped a generation. However, because there aren't any definitive links between genes and hyperovulation and because twins don't predictably always skip a generation, it's likely just a coincidence when it does occur.
It sounds impossible. But thanks to the reproductive advancements of surrogacy and in vitro fertilization, twins Connor and Cameron Payne were born to different mothers 16 days apart in different hospitals.
In 99.9% of cases boy/girl twins are non-identical. However, in some extremely rare cases resulting from a genetic mutation, identical twins from an egg and sperm which began as male (XY) can develop into a male / female pair.
Just over 3 percent of babies in the United States are now born in sets of two, three or more, with the majority — about 97 percent — of these multiple births being twins. So your chance of having twins is about 3 in 100.
Most often, fetuses known in utero as twin A are also first born and thus retain their label. However, this is not always the case, such that the twin A newborn was previously labeled twin B in utero and vice versa.
A dad who's one of a twin may inherit the gene, but it won't increase his chances of having twins too, because the gene only affects ovulation. The same dad may pass on the gene to his daughter, who then goes on to get pregnant with twins, making it look like twins have skipped a generation .
The birth process is similar to giving birth to a single baby. If you're planning a vaginal birth, your health team may recommend that you have an epidural for pain relief.
Fertility treatments can play a big role in increasing the likelihood of having twins. In particular, assisted reproductive technologies such as in vitro fertilization (IVF) and ovulation-stimulating medications can make a person more likely to conceive twins.
Classically, the bigger twin is the more physically dominant. It's basic human nature, and particularly applicable to boys as they hit puberty. It happens often with singleton siblings too… the older is bigger and enforces him/herself through physical dominance.
If a woman's sister has fraternal twins, she is about 2.5 times more likely to have twins herself. If a woman's mother has fraternal twins, she is about 2 times more likely to have twins. This is why we often say the “risk” for having twins comes from the mother.