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.
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.
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.
In addition, previous studies have shown that first-born twins are, on average, taller and heavier than second-born twins until adolescence (Silventoinen et al., 2007; Pietiläinen et al., 2002).
It is inferred that superfecundation by the same man is relatively common and that therefore dizygotic twins quite often have different gestational ages.
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.
The longest interval between the birth of twins is 90 days, in the case of Molly and Benjamin West, dizygotic (fraternal) twins born in Baltimore, Maryland, USA to parents Lesa and David West (all USA) on 1 January and 30 March 1996.
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.
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.
Some say that twins are always hard (yet amazing), while others say they truly didn't find them to be difficult. A few said that the first two months with twins are easy (being in the rose-colored glasses phase), then reality hits from months 3-6 (when the sleep deprivation catches up), then it can get easier again.
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.
The dominance and submissive behaviour in twins may not be the same under all circumstances. This means, that there is no need for the same twin to be dominant in all scenarios.
There is one particular power though which twins possess, longevity. Fraternal twins live longer than singletons and identical twins longer still. Male identical twins on average, saw the most benefit.
But then, to everyone's surprise, she gave birth to two – in the space of just six-and-a-half months. Against all the odds, Ronnie and his little sister Sienna were born only 208 days apart. Miss Budden, 31, a pre-school teacher, was stunned to get pregnant three weeks after Ronnie was born.
Are twins hereditary? Yes, some types of twins are hereditary, meaning that twins run in families. Heredity on the mother's side ups a couple's odds of conceiving fraternal twins. Fraternal twins are two babies from two different eggs that were released from the ovaries simultaneously.
Vanishing twin syndrome was first recognized in 1945. This occurs when a twin or multiple disappears in the uterus during pregnancy as a result of a miscarriage of one twin or multiple. The fetal tissue is absorbed by the other twin, multiple, placenta or the mother. This gives the appearance of a “vanishing twin.”
Dizygotic twins are the most common type and are known as fraternal twins. Two-thirds of all sets of twins are dizygotic. When two eggs are fertilized during the same pregnancy, the result is a set of dizygotic twins. They are fertilized by two different sperm.
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.
This is supported by a Dutch study of adult twins, which found no significant difference in IQ between singletons and twins from the same families.
Multiples are generally born only a few minutes apart. If delivered by cesarian section, the interval between births is usually only a minute, maybe two. The interval is generally longer for vaginal deliveries, ranging from a few minutes to more than an hour.
Age. 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.
Vaginal Birth of Twins
This means you will have to push twice, but the majority of the time the second twin is born much more easily than the first. This is because the first twin has paved the way, so to speak. The average time between the birth of the first and second baby is generally about 17 minutes.