What do twins share

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On this page. Multiple births are more common than they were in the past, due to the advancing average age of mothers and the associated rise in assisted reproductive techniques, in particular the use of fertility drugs. Twins account for over 90 per cent of multiple births.

There are two types of twins — identical monozygotic and fraternal dizygotic. To form identical twins, one fertilised egg ovum splits and develops two babies with exactly the same genetic information. This differs from fraternal twins, where two eggs ova are fertilised by two sperm and produce two genetically unique children, who are no more alike than individual siblings born at different times.

Twins are more or less equally likely to be female or male. Factors that increase the odds of having twins Some women are more likely than others to give birth to twins. The factors that increase the odds include: Advancing age of the mother — women in their 30s and 40s have higher levels of the sex hormone oestrogen than younger women, which means that their ovaries are stimulated to produce more than one egg at a time.

Number of previous pregnancies — the greater the number of pregnancies a woman has already had, the higher her odds of conceiving twins. Heredity — a woman is more likely to conceive fraternal twins if she is a fraternal twin, has already had fraternal twins, or has siblings who are fraternal twins.

Race — Black African women have the highest incidence of twins, while Asian women have the lowest. Dizygotic twins form from two separate eggs that are fertilized by two separate sperm. They may be different sexes or the same sex. Monozygotic , or identical, twins are always assigned the same sex at birth. While fraternal twins share similarities with each other, those similarities are comparable to siblings from separate pregnancies.

So although they may look very much alike as siblings often do , fraternal twins are not identical. It's true that multiples can share a special connection that goes beyond that of ordinary siblings. Sometimes they will say or do the same thing at the same time.

Some twins relate incredible stories of coincidence, where they think the same thoughts or sense each other's feelings. Older studies on twin relationships have indicated that twins may share a stronger bond than non-twin siblings. However, more recent research has found no difference between twin and non-twin sibling relationships in terms of how they behaved toward one another.

While there may be anecdotal evidence for a strong bond between multiples, there is not sufficient research to conclude that twin telepathy exists. In times past, twins were often a surprise to their parents. Instead of one baby, two arrived!

But now that ultrasound allows a sneak peek into the womb, there are rarely instances of a hidden twin. Despite the clarity of modern technology, multiples still manage to pull a few surprises and remain hidden from view during a portion of pregnancy. This is more likely to happen if your ultrasound was done before 20 weeks, you didn't have an ultrasound, or if you have not received prenatal care. According to the American Speech-Hearing-Language Association, what appears to be a secret language between twins may actually be a delay in phonology rules used to put speech sounds together.

Some twins use a secret language with one another and communicate effectively with others, like parents, so it's not always an indicator of a problem.

However, secret twin language may be a risk factor for speech and language delays. If you are unsure whether your twins' secret language could indicate a speech delay, contact a speech-language therapist for an evaluation.

They will be able to help you determine if your children's speech patterns are developmentally appropriate. Anyone who knows a set of identical twins knows that they are alike in many ways, but also very unique individuals. Why is that? While twins often look very similar and may even share some of the same tastes and interests, they're also very different.

Identical twins form from a single egg and sperm combination and share the same genes, but environmental factors can influence differences in in twins' characters.

Twins, by definition, are two offspring born together, right? Yet, some twins blow out their candles on different days. Often, twins are born minutes apart—sometimes that interval just happens to be as a day or year changes over. But, other times, the span between each twin's birth can be even greater. When a pregnancy has a complication, such as preterm birth, a practice called delayed interval delivery may be used to stop labor after the birth of the first baby, allowing the other time to develop more fully before they are born.

This is very rare, but there have been case reports of delayed interval delivery of a month or more between births. Monozygotic twins occur when a single egg is fertilized by a single sperm. The zygote then splits in early pregnancy, forming identical twins. In this case, both twins share an inner sac , called the amnion, in addition to sharing a placenta.

The technical name for this is monoamniotic twins. For example, a twin who receives less blood from a shared placenta might weigh less at birth. Sharing a placenta means that twins share a blood supply during pregnancy. Sometimes the blood supply is shared unequally, which can cause health problems for both twins.

Women who are pregnant with twins sharing a placenta need to be checked more often than women with twins with separate placentas. Frequent checks can pick up early on any potential complications. Twins sharing an inner sac monoamniotic are also at a higher risk of complications during pregnancy because of the chance that their umbilical cords might tangle and cut off their blood supply. These twins are checked even more closely.

Medical professionals often recommend that these twins are born earlier than other types of twins. Medical professionals use ultrasound to work out how many placentas twins have. The earlier the ultrasound, the more accurately it can say how many placentas there are. It gets harder to work out later in pregnancy.

After the birth, the placentas should be looked at to confirm or determine what type of twins they are. Fraternal twins can be of the same or different sexes. Identical twins are also called monozygotic twins. They result from the fertilization of a single egg with a single sperm. And as those cells divide and multiply, at some point very early in embryonic growth they split into two individuals.