Are Twins Born on the Same Date?

  • Thread starter Thread starter pivoxa15
  • Start date Start date
Click For Summary
The discussion centers on the misconception that siblings born within 365 days of each other must be twins. It clarifies that while twins are conceived simultaneously, siblings can be born within the same year without being twins. The typical human gestation period is about 275-280 days, allowing for the possibility of one child being born in January and another conceived shortly after, resulting in a December birth. Factors such as breastfeeding can delay ovulation, but it is still possible for siblings to be born in the same year. The conversation also touches on the rarity of certain phenomena, such as superfetation, where two embryos develop from different ovulations. Additionally, it highlights that non-identical twins can look quite different, similar to siblings born years apart, due to genetic variation and environmental factors. The discussion concludes with insights on the impact of parental age on egg and sperm quality, emphasizing that older parents may face increased risks of genetic defects in their children.

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.
 
Biology news on Phys.org
  • #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.
 

Similar threads

  • · Replies 31 ·
2
Replies
31
Views
3K
  • · Replies 12 ·
Replies
12
Views
5K
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 10 ·
Replies
10
Views
5K
  • · Replies 35 ·
2
Replies
35
Views
3K
  • · Replies 20 ·
Replies
20
Views
3K
  • · Replies 47 ·
2
Replies
47
Views
4K
  • · Replies 7 ·
Replies
7
Views
6K
  • · Replies 5 ·
Replies
5
Views
10K