How do twins decide who comes out first?

For vaginal delivery of both infants, the twins decide birth order by their placement in the uterus. Once the babies are large enough to stay in one position in the womb, the twin lowest in the uterus is known as Baby A and the one furthest from there is Baby B, according to the Stanford Medicine News Center.

Is twin A or twin B conceived first?

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.

Is the twin that comes out first older?

Which twin is older? The oldest twin is the one who is born first. It doesn't matter whether twins are born vaginally or by C-section; the first one out of the womb is considered the oldest. This may be the baby who was labeled baby A during the ultrasounds, but it might not if the other one makes it out first.

Does birth order affect twins?

However, many birth order experts agree that twins tend to organize themselves according to their overall place within the family. 2 For example, if they have one older sibling, they will both exhibit characteristics of a second born. If they are the oldest, they will adopt some traits of firstborns.

Do twins come from the mom side or dad side?

For a given pregnancy, the odds of conceiving fraternal twins are only determined by the mother's genetics, not the father's. Fraternal twins happen when two eggs are simultaneously fertilised instead of just one.

How Early Can You See Twins On A Scan?

Which parent holds the twin gene?

The gene versions that increase the chance of hyperovulation can be passed down from parent to child. This is why fraternal twins run in families. However, only women ovulate. So, the mother's genes control this and the fathers don't.

Who carries the twin gene?

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.

Which twin is usually bigger?

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.

What is the divorce rate for parents of twins?

They found that twins at first birth were linked to higher divorce rates at 13.7% compared to 12.7% for singletons. The link was statistically higher among moms attending college at 14.4% with twins vs. 10.5% with single births.

Do hospitals charge more to deliver twins?

Double Kids, Not Exactly Double Expenses

Your hospital stay as the mother costs about the same with one baby or two. However, each of your babies will get their own charges for in-hospital care.

Which twin is rarest?

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.

Does the smaller twin come out first?

Once the babies are large enough to stay in one position in the womb, the twin lowest in the uterus is known as Baby A and the one furthest from there is Baby B, according to the Stanford Medicine News Center. In the majority of vaginal births, Baby A is born first.

What age is most common for twins?

People over 30, and particularly those over age 35, are more likely to conceive twins. 4 This is because the level of follicle-stimulating hormone (FSH) rises as birthing parents get older. FSH is responsible for the development of eggs in the ovaries before they are released.

How do they determine which twin is baby A?

In prenatal ultrasounds, the baby positioned lowest in the uterus is given the designation of “Baby A.” Under this convention, Baby A will likely be born first in a vaginal delivery. However, about 75 percent of twins are delivered by cesarean section.

Which twin is most likely to have twins?

According to The American Society for Reproductive Medicine, women who are fraternal twins have a 1 in 60 chance of having twins, and men who are fraternal twins have a 1 in 125 chance of fathering twins.

What is the first twin called?

Throughout pregnancy, we refer to twins as 'first and second' or 'left and right' or 'the cephalic one', 'the breech one', 'the transverse one'.

Why do mothers of twins live longer?

Having two babies at a time is associated with a longer life, according to a new study. But that's not because doubling up on dirty diapers increases life span; instead, moms of twins are physically stronger in the first place.

What do parents of twins need most?

Do twins have anything to do with the father?

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. 3 But, if a father passes on the "twin gene" to his daughter, then she may have a higher chance than normal of having fraternal twins.

What is a normal birth weight for twins?

Twins and triplets often don't have a chance to reach a healthy weight before they're born. While the average single baby weighs 7 pounds at birth, the average twin weighs 5.5 pounds. Triplets typically weigh 4 pounds each, and quads weigh 3 pounds each.

What gender is most common in identical twins?

Identical twins turn out as the same gender about 99.9% of the time.

What are the 3 types of twins?

Is there a third type? Traditionally, the science around twins has taught that identical and fraternal are the only two types. But a third type might exist, called polar body or half-identical twins.

Does having twin skip a generation?

Many people believe twins skip a generation, but that's just a myth. The idea that twins skip generations likely comes from the fact that the genetic factors contributing to twins only come from the gestational parent's side.

Can you have twins if they don't run in your family?

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.

How do twins run in families?

Some research has found that having fraternal twins in a mother's immediate family may double the chances of conceiving fraternal twins. One theory is that it's because a certain gene may predispose some women to "hyperovulation," or releasing more than one egg during each menstrual cycle.