The fetus with more blood flow is called the recipient twin, and the fetus with less is called the donor twin. Because the donor twin has less blood flow, this baby grows slower and is smaller.
Most twin, triplet or more babies will be slightly different in size, but sometimes 1 baby is significantly smaller than the other/s. This is called 'selective' fetal growth restriction. Selective fetal growth restriction occurs in 10-20% of multiple pregnancies.
Depending on where they implant, one twin may get a smaller share of the placenta than the other, resulting in less blood flow and nutrition to one fetus, and more to the other. This is called unequal placental sharing. As a result, the twins may grow differently.
As expected, first-born twins had greater birth weight than second-born twins. With respect to height, first-born twins were slightly taller than second-born twins in childhood.
So the firstborn is really the youngest. Answering the “which twin is older” question from strangers is one thing. Fielding the questions from friends, family, or the twins themselves is another story. You should discuss as a couple your approach for answering this question with people you know.
To. Compute. Knowing which twin is the older one is usually a no-brainer. The time of birth is recorded, and whichever one is born first is officially the eldest.
Monoamniotic-monochorionic Twins
This is the rarest type of twin, and it means a riskier pregnancy as the babies can get tangled in their own umbilical cords. If you have monoamniotic-monochorionic twins, your healthcare provider will monitor your pregnancy closely.
Alba's twins were monoamniotic-monochorionic and shared the same placenta, amniotic sac and fluid. MoMo twins are some of the rarest types of twins, making up less than 1 percent of all births in the United States.
Most twins, triplets and more grow and develop along roughly the same lines as their singleton peers – even those who start out much smaller will catch up in time.
Barring pregnancies that result from assisted reproductive technology, dizygotic twins are far more common than monozygotic twins and account for 70 percent of all twin gestations.
The incidence of handicap was 3.7% in twins, 8.7% in triplets, 11.1% in quadruplets, and 10.0% in quintuplets. The risk of producing at least 1 handicapped child was approximately 1 in 13 pairs of twins (7.4%), 1 in 4 or 5 sets of triplets (21.6%), and 1 in 2 sets of quadruplet and quintuplets (50%).
It is estimated that 1 in 250 natural pregnancies will naturally result in twins. While twin pregnancies can happen by chance, there are some factors that may increase your odds of having two babies at the same time. Let's learn about twins!
Some identical twins can have different heights and weights. This is because height and weight are controlled by what you eat as well your DNA. Differences in diet can start earlier than you might imagine. When the twins are growing inside the uterus, there can be differences in how well they connect to the placenta.
Since bed rest is common for women pregnant with twins after 30 weeks—or 7.5 months—be prepared to go on maternity leave earlier than you'd think, just in case. “Having twins is not twice as hard—it's exponentially more difficult.”
The short answer is no, even twins develop at different rates. Even though they share so much in common, twins are still two unique people and have many individual differences. Just how one may prefer bananas and the other applesauce, they also develop differently!
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).
Identical twins
Identical (monozygotic) twins happen when a single egg (zygote) is fertilised. The egg then divides in 2, creating identical twins who share the same genes. Identical twins are always the same sex, so if your twins are identical, you'll have 2 girls or 2 boys.
The DNA of monozygotic twins tends not to be 100% identical, and epigenetic and environmental differences further widen the gap between twin pairs. It's not nature or nurture; it's a complex interaction between our genes, our environment, and our epigenetic markers that shape who we are and what illnesses befall us.
Twins are more or less equally likely to be female or male. Contrary to popular belief, the incidence of twins doesn't skip generations.
Identical twins are less common than fraternal twins. Identical twins happen in about 3 to 5 out of every 1,000 births. While fraternal twins tend to run in families, identical twins don't.
“Some of the cells contain the chromosomes from the first sperm while the remaining cells contain chromosomes from the second sperm, resulting in the twins sharing only a proportion rather than 100% of the same paternal DNA,” clinical geneticist Dr.
However, for a given pregnancy, only the mother's genetics matter. Fraternal twins happen when two eggs are simultaneously fertilized instead of just one. A father's genes can't make a woman release two eggs. It sounds like fraternal twins do indeed run in your family!
There is no right or wrong answer, it's a personal preference. Some chose to be completely open or tell their twins to give a “smaller” twin leverage if he/she is older. Other choose not to tell so that they don't bicker about the subject or the dominate “older” twin doesn't have more leverage.
According to Stanford, the likelihood of twins during any particular pregnancy comes from the mother, because, as they put it, "A father's genes can't make a woman release two eggs." If you're the woman who is trying to conceive though, it's not just your mom's genetics that matter.