A news story this morning says that a woman has conceived two babies two and a half weeks apart. Extremely rare in humans but common in the animal world. Doesn’t say if she had taken fertility drugs. I wonder if that is what caused it.
I thought “twins” were two babies born on the same day. Does “conceived at the same time” have anything to do with it? If these babies are born on the same day (by Cesarean, for example) I would have called them twins, normally, had I not had the benefit of seeing this report.
Twinning does not necessarily imply splitting of one embryo. I myself am a twin, but a non-identical twin, born seven minutes before my brother. I don’t know anything about our conception times – thank God – but would I qualify as a case of what the report is describing?
I’m pretty sure most fraternal twins occur because two eggs were released at about the same time, and two different sperm fertilize them. So they’re no more closely related genetically than other siblings. This case seems to be special because one egg was fertilized, implanted, and then another egg was released about 2 weeks later and was also fertilized and succesfully implanted. Typically the body is supposed to halt further ovulation once the woman becomes pregnant, IIRC.
Twins are conceived at approximately the same time. These babies were conceived two and half weeks apart. One baby is due in Dec. 2009, the other is due in Jan. 2010.
There is one case on record where a woman had two babies born at the same time with two different fathers.
I believe the definition of twins is any two fetuses that share the uterus at the same time. But it’s not really worth arguing about, because this is such an extreme case you’d expect the definition to break down. In the past, fetuses with wombmates were always conceived at the same time, or close enough, so both parts of the definition were congruent.
Anyway, I wonder if the younger fetus will possibly wait out his older sibling’s labor and birth. I’m no obstetrician, but you have to figure they’re comin’ out at the same time.
–Cliffy
I’m with Cliffy, but that is by no means an expert opinion in any way. Just my personal opinion. I can see where the others are coming from, though.
On the occassions a woman ovulates twice in one month, it’s almost always within the same 24-hour period. Most fraternal twins are conceived within that time period.
At 2.5 weeks, the first embryo would already have implanted in the mother’s uterus, so she shouldn’t have ovulated a second time at all. This is, in fact, a really strange case.
They probably will generally be referred to as twins, but the circumstances are very unusual.
I know you can miscarry one fraternal twin, and not the other, so who knows?
I don’t know if there are any cases of one being born significantly later than the other, but since most fraternal twins are conceived so closely together, it’s not that likely to happen, anyway, since they’d be due at the same time.
Yo dawg I herd u liek babby…
Yeah - it’s quite rare. A friend of mine is reasonably certain it’s what happened with her twins, given a number of factors (including the fact that though both were somewhat premature, one exhibited significantly more symptoms of prematurity than the other, in line with being conceived 2+ weeks later). But of course they don’t have proof, this would be a very tough one to prove unless someone was being monitored pretty intensively around the time(s) of conception.
I wonder if it’s possible one wombmate can consume more of the resources, somehow slowing the development of the other?
Yes, that’s quite possible. Usually, though it’s at an earlier stage where one can win out over the other if you will for resources, and there’s only one baby produced, but even into later stages there can be nutrient competition.
“Superfetation?” There’s nothing super about it. I thought a nice thing about being pregnant was that you can have all the sex you want and not get pregnant again.
My wombmate kicked me in the chest. Don’t know if it slowed my development but I was born with an already-healed fractured rib. You can still feel the lump where the bone fused.
Bastard.
Would DNA tests be conclusive as to who fathered which baby?
I can’t get that video to work, do they say what they’re going to do for delivery? I’m curious. It seems like one would just have to be born a few weeks premature, but maybe they say differently?
Oh gee . . . I almost stopped reading after the word “consume.” It looked like you were going in an entirely different direction. :eek:
Nope. Twins can be born days apart.
BTW: When you link to an article, please try to find a way to do so where it won’t change, so later posters can still use it. In your case, you needed to search for the video on Yahoo! News. The link is
http://cosmos.bcst.yahoo.com/up/player/popup/?rn=3906861&cl=15717718&ch=4226723&src=news
Hee, like The Dark Half, with that eyeball in the guy’s brain?!? shudder
Well, that could provide clues in the case of a woman being certain she had sex with fellow A on the first, and fellow B on the 15th… in the case of my friend however, both babies were likely fathered by her husband 