Twins that do not have the same birthday are known as “counter-part twins”. These types of twins are the result of two separate fertilized eggs that are released from the mother’s ovaries at different times.
Since the eggs were released at different times and gestated for different lengths of time, the babies are born on different days. Counter-part twins are also known as fraternal or non-identical twins as they do not share a placenta, which is the case with identical twins.
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What are the 4 types of twins?
There are four main types of twins: Identical (or monozygotic) twins, Fraternal (or dizygotic) twins, Mixed Chromosome (or Polar Body) twins, and Half-Identical (or sesquizygotic) twins.
Identical (or monozygotic) twins occur when a single egg is fertilized by a single sperm, leading to a single embryo that then splits into two embryos. As this occurs in the very early stages of embryonic growth, they share the same genetic material, meaning they are the same sex and have similar physical characteristics.
Fraternal (or dizygotic) twins occur when two different eggs are fertilized by two different sperm, leading to two embryos. As these develop separately, they have different genetic codes which will affect their physical appearances and genders.
Mixed Chromosome (or Polar Body) twins occur when an egg splits into two unequal parts before fertilization, resulting in two embryos that do not share the same genetic material. This type of twinning is very rare.
Finally, Half-Identical (or sesquizygotic) twins occur when two separate eggs are fertilized by two sperm from the same person. This results in two embryos that share one-third of the same genetic material.
This means that the two embryos will share physical characteristics from both of the parents, but will not match as twins usually do.
In summary, the four main types of twins are Identical (or monozygotic), Fraternal (or dizygotic), Mixed Chromosome (or Polar Body), and Half-Identical (or sesquizygotic).
What is a birthday twin?
A birthday twin is someone who shares your birthday, meaning they were born on the same day and in the same year as you. This could be someone you know or a stranger you’ve never met, and can even be across the world.
Some people refer to birthday twins as birthday soulmates and believe that certain things are predetermined by the date of birth, so there is often an emotional and spiritual connection shared between them.
With some even helping to arrange meetings and reunions.
Can twins have different due dates?
Yes, twins can have different due dates. This is known as being late splitting twins, and it occurs when twins’ placentas become separated after initial implantation in the uterus. Due to this delay, the twins can be born at different times, often with a difference of a week or even more.
Typically, the baby that initially implanted later is born first.
This phenomenon is relatively rare, occurring in just 5-25% of twin pregnancies. Factors that may increase the risk of late-splitting twins include multiple gestations, an increase in prenatal care, and an increased maternal age.
Symptoms of this phenomenon include a longer waist circumference, a larger blood volume in one twin, and advanced fetal growth in only one of the twins.
Because this phenomenon is so rare, it is important for mothers carrying twins to receive close medical monitoring throughout the entirety of their pregnancy in order to detect any potential differences in development or growth.
Additionally, mothers of twins can be reassured that both of their babies will have similarly healthy outcomes.
Can a twin be born years later?
Yes, it is possible for a twin to be born years later. This type of delayed twin birth is referred to as Superfetation. Superfetation occurs when two separate eggs are released during ovulation and are fertilized separately.
This results in siblings of different gestational ages within the same pregnancy. It is estimated that the frequency of superfetation is approximately 1 in 20,000 to 1 in 80,000 births. Superfetation can result in a wide age gap between siblings, with one twin being born weeks, months, or even years after the other.
The vast majority of medically reported cases of superfetation occurred in human pregnancies, but cases have been seen in animals as well. The phenomenon of late-term superfetation is very rare and it may not be detected until after birth.
What are twins called that are 11 months apart?
Twins born 11 months apart are known as “Irish Twins” because in the early 19th century, Irish families often had children close together in age due to the country’s poverty. Irish Twins don’t have to be of the same gender, but they could both be boys or both be girls.
However, if the twins have different genders, they would technically be siblings rather than twins. Additionally, the term “Irish twins” is more of a colloquialism and not technically correct, as it implies twins are born within the same calendar year, which is not necessary.
What are Eskimo twins?
Eskimo twins, also known as dizygotic twinning, is the term used to refer to twins who are born at the same moment but are not identical. These twins are fraternal in nature, meaning that they develop from separate eggs that have been fertilized by separate sperm.
This type of twinning is more common than monozygotic twinning (AKA identical twins) and is also more common among certain ethnicities, including that of the Eskimos. While the exact cause of Eskimo twins is unknown, researchers point to certain environmental and genetic factors as potential causes.
For instance, a mother’s diet, her age, and her reproductive history might all be factors in the occurrence of Eskimo twins. Interestingly, while the rate of Eskimo twins vary significantly across different populations, Eskimos (the native people of Siberia, Alaska, and Canada) tend to have higher rates of dizygotic twinning.
What birth defects are common in twins?
Twin pregnancies may present various risks which can lead to various types of birth defects, such as those related to preterm birth, growth restriction, birth asphyxia and others. Some of the most common birth defects in twins are prematurity, twin-twin transfusion syndrome (TTTS), intrauterine growth restriction (IUGR), hydrops fetalis, congenital diaphragmatic hernia (CDH), Cerebral Palsy, and anomalies of the nervous system.
Prematurity is one of the most common birth defects experienced by twins. This can sometimes be the result of preterm labor or preterm rupture of the membranes. TTTS, where the blood flows from one twin to the other twin, is also common.
This can lead to a variety of complications, including birth weight discrepancies, and can also increase the risk of prematurity. IUGR is another common birth defect in twins, where one or both twins experience restricted growth in the womb.
Contrary to common belief, it’s not always one twin that is affected, but sometimes both. babies born with IUGR are at higher risk of experiencing other birth defects, such as hydrops fetalis, a set of signs and symptoms that reflect fluid accumulation, Cerebral Palsy, and anomalies of the nervous system.
This is also known as Rh isoimmunization.
The risk of birth defects is higher in multiple pregnancies, so it’s important to make sure that you receive regular, thorough prenatal care to check for potential problems.
Which twin is conceived first?
The twin that is conceived first is determined by the point of fertilization. If the egg splits after fertilization then both babies will be the same age, but if it splits before, the twin that was conceived first will be slightly older.
As for which baby is actually conceived first, this is dependent on the timing of the egg’s release from the ovary and the timing of the sperm cells that reach and fertilize the egg. The medical community avoids the concept of a “first-conceived” twin because it entirely depends on the exact timing of ovulation and insemination, which is impossible to accurately determine.
Is fraternal twin pregnancy high risk?
Yes, fraternal twin pregnancy can be considered high risk. This is because multiple pregnancies often come with more health risks than a singleton pregnancy. There is an increased risk of preterm labor due to the excess weight of the two babies in the womb, and there is an increased risk of the mother developing high blood pressure and gestational diabetes.
Additionally, due to the extra space each fetus needs, there may be an issue with the placenta not providing enough nutrients to both babies. Also, when twins are in the same amniotic sac (monochorionic pregnancy), this can lead to scenarios whereby one twin absorbs nutrients from the other, leading to Issues such as twin-to-twin transfusion syndrome.
Having fraternal twins may also come with longer hospital stays for both mother and babies, as well as specialized care for neonatal intensive care. Therefore, it is best to have a doctor closely monitor any twin pregnancy from the start.
What is the chance of miscarriage with twins after seeing heartbeat?
The chance of miscarriage with twins after seeing a heartbeat varies from individual to individual. Generally, the first trimester (the first 12 weeks of pregnancy) is considered the highest risk period for twins, with a higher risk for early miscarriage and other complications compared to singleton pregnancies.
When twins are seen on an ultrasound and a heartbeat is detected, this can be interpreted as a positive sign, although it is important to note that no pregnancy is ever 100% guaranteed and the risk of miscarriage still exists even after a heartbeat has been noted.
A study conducted by the Institute of Mineromic Sciences found that 33% of women carrying twins experienced a miscarriage after detecting a heartbeat.
It is important to heed the advice of your healthcare provider if you are expecting twins. They can provide you with tailored information regarding the risks associated with your own particular case and can equip you with the knowledge and support you need.
How early can you safely deliver twins?
It is recommended that twins are delivered at 37 weeks of gestation, which is considered full-term. Most twins have slightly higher rates of preterm labor due to the added strain on the body. It is important to monitor fetal well-being closely and to plan for delivery when need be.
It is safe to deliver twins as early as 36 weeks, although the risks for infant morbidity and mortality increase with each passing week after 32 weeks.
In some cases, delivery may need to be induced or an immediate c-section may be needed if there are signs of distress from either baby. It is important to follow the direction of your health care provider and to be attentive to any signs of preterm labor such as regular contractions, vaginal bleeding, or leaking or gushing of fluid.
Close monitoring is important to ensure the health of both babies and mother.
