Are Twins Born on the Same Date?

  • Thread starter Thread starter pivoxa15
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Discussion Overview

The discussion centers around the question of whether two siblings born within the same year can be considered twins, exploring the definitions of twins, gestation periods, and the conditions under which siblings can be born in close temporal proximity without being twins.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • Some participants argue that twins must be born on the same date, while others clarify that siblings can be born within the same year without being twins.
  • It is noted that the gestation period for humans is approximately 275-280 days, allowing for the possibility of siblings being born in the same year but not as twins.
  • Several participants mention that conception can occur after the birth of the first child, leading to siblings born in the same year but at different times.
  • There is discussion about the possibility of twins being conceived from different fathers, which some participants find surprising.
  • Some participants express confusion about the terminology used, particularly regarding conception and gestation, emphasizing the importance of clarity in definitions.
  • One participant shares a personal anecdote about having a sibling born 14 months after them, illustrating the point that siblings can be born at different times.
  • There is mention of the phenomenon of heterozygote twins, where two different embryos are fertilized at the same time, leading to twins that may not share the same genetics.

Areas of Agreement / Disagreement

Participants generally agree that it is possible for siblings to be born within the same year without being twins, but there is no consensus on the definitions and implications of being a twin, leading to multiple competing views.

Contextual Notes

Some participants highlight the variability in gestation and conception timing, as well as the influence of factors like breastfeeding on ovulation, which may affect the likelihood of having siblings born close together in time.

Answer to question in OP

  • Yes

    Votes: 1 7.7%
  • No

    Votes: 12 92.3%

  • Total voters
    13
  • #31
fraternal twins are dizygotic twins - twins formed from two separate eggs combined with two separate sperm. Creates two individuals. Not necessarily the same sex and definitely not with the same genes.

identical twins are monozygotic - formed from a single egg combined with a signle sperm.
The zygote divides forming another identical zygote. Each one (total of 2) goes on to form a separate individual. You get 2 people of the same sex with identical genes.

-- just to clarify. You guys are throwing terms around and it is confusing to other readers.
 
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  • #32
pivoxa15 said:
Birth defects being the genes not properly transcribed and carried out?

When that happens at a minor level, the effects will show later in the baby's life?

What do you mean by degrade of sperm and egg?

fraternal twins being twins with different fathers?

"Birth defects" simply means any wrong development in the baby, whether caused by genetic damage, trauma (injury), or chemicals.

By "degrade" I mean genetic damage or possibly weak sperm (that can't swim well).

Fraternal twins mean twins that aren't identical.

The older the parent, the more likely the genes in the egg or sperm will be damaged (because cells have had longer to get damaged), and thus the less likely a fetus will be viable and if it does grow the more likely it will have genetic defects. Its a higher probability but still fairly low. Down syndrome is the classic example--the probability increases substantially as a mother gets into her 40's, but even then its something like 1/600 if memory serves me. Typically genetic damage is apparent early on--its affects aren't necessarily that delayed or hidden.

Xenoestrogens typically won't cause genetic damage in a fetus, however they can cause genetic damage in that fetus's offspring (by messing up the fetus's ability to create good sperm or eggs)! Xenoestrogens alter the development of the baby just like too much estrogen would. They collect in people and so are more dense in older people. Xenoestrogens cause feminization of male babies, damage to the fetu's ability to create sperm or eggs, early puberty in girls, and other things. They also pretty much explain why men's sperm counts have dropped so profoundly in the last few decades. Xenoestrognes in adults are the prime cause of some common cancers and other things.

Here's a good starting point to see all the studies that have been done that clearly show these things are happening. Also you'll see how doctors often treat patients with xenoestrogens thinking they will help certain problems when they simply exacerbate them (like menopausal symptoms). (Note that the pharmaceutical companies only push non-natural substances because they aren't allowed to patent natural substances, and that pharmaceutical salesmen are often the only source of information a doctor has because doctors are too busy to read the journals propounding the studies!)

Here's the link:
http://www.johnleemd.com/store/resource_references1.html

.
 
  • #33
Moonbear said:
It takes some time for ovulations to resume after one gives birth, though that time varies among individuals and whether or not one is breast feeding. But, still possible to have a baby born in January and another in December (especially if the second is a bit premature).

Even if it's the normal way that a woman recovers from childbirth this isn't always the case. I have two cousins who are roughly nine months apart. I don't remember their birthdays exactly but I know it's nine months & a week or two. Lol, the doctor told my uncle to let the stitches heal next time. Anyway, to answer pivoxa15's original question no, two babies born in the same year don't have to be twins.

pivoxa15 said:
Still, eggs produced within a period of time can be different to eggs produced at a later time. Same as sperms.

Actually women are born with all the eggs they will ever have, not 100% sure of the number but I think it's in the neighborhood of 40,000 eggs.
 

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