# two babies not twins **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [September 24, 2009, 12:12pm UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360 "2009-09-24T12:12:01Z")\ **Posts on this page:** 12\ **Page:** 2
**Author:** ![wolfstu](https://avatars.discourse-cdn.com/v4/letter/w/d6d6ee/32.png) [@wolfstu](https://boards.straightdope.com/u/wolfstu)\ **Post date:** [September 25, 2009, 3:43pm UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360/21 "2009-09-25T15:43:11Z")
> [@Sailboat](#): > > My wombmate kicked me in the chest. > . . . > Bastard. There’s something amusing about insulting the parentage of someone you shared a womb with. 😉 ---
**Author:** ![purplehorseshoe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/purplehorseshoe/32/2996_2.png) [@purplehorseshoe](https://boards.straightdope.com/u/purplehorseshoe)\ **Post date:** [September 25, 2009, 3:59pm UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360/22 "2009-09-25T15:59:38Z")
> [@Ro0sh](#): > > 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. A friend of mine is half of a set of fraternal twins, and she said her twin brother was born much bigger and robust than she was, plus she’s always had asthma and a few other chronic medical issues, while he’s healthy as the proverbial horse. ---
**Author:** ![Arglefraster](https://avatars.discourse-cdn.com/v4/letter/a/3bc359/32.png) [@Arglefraster](https://boards.straightdope.com/u/Arglefraster)\ **Post date:** [September 25, 2009, 4:03pm UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360/23 "2009-09-25T16:03:40Z")
> [@MissIntent](#): > > 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? If the mother carries to term, it shouldn’t be an issue. From what I’ve read, most babies can be born up to 3 weeks early with no issues whatsoever, and from 4 to 8 weeks early with only minor problems. ---
**Author:** ![gigi](https://avatars.discourse-cdn.com/v4/letter/g/a587f6/32.png) [@gigi](https://boards.straightdope.com/u/gigi)\ **Post date:** [September 25, 2009, 6:07pm UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360/24 "2009-09-25T18:07:49Z")
> [@purplehorseshoe](#): > > A friend of mine is half of a set of fraternal twins, and she said her twin brother was born much bigger and robust than she was, plus she’s always had asthma and a few other chronic medical issues, while he’s healthy as the proverbial horse. In a sad example of a FOAF, her one girl’s blood supply had to pass through the other girl first. Second girl’s heart had to pump doubly hard and little girl of course didn’t grow normally. They were delivered super-early and little girl died. ---
**Author:** ![Cliffy](https://avatars.discourse-cdn.com/v4/letter/c/59ef9b/32.png) [@Cliffy](https://boards.straightdope.com/u/Cliffy)\ **Post date:** [September 26, 2009, 7:19am UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360/25 "2009-09-26T07:19:53Z")
> [@Sailboat](#): > > 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. Just be glad your twin wasn’t Professor X! > [@Ruby](#): > > Would DNA tests be conclusive as to who fathered which baby? If the parentage were in doubt? Sure, unless the two potential fathers were identical twins. > [@gigi](#): > > In a sad example of a FOAF, her one girl’s blood supply had to pass through the other girl first. Second girl’s heart had to pump doubly hard and little girl of course didn’t grow normally. They were delivered super-early and little girl died. Awful. Sounds to me like they were identical twins, though. Fraternal twins have their own placentas and blood supply, because those structures are formed from the fertilized egg. –Cliffy ---
**Author:** ![gigi](https://avatars.discourse-cdn.com/v4/letter/g/a587f6/32.png) [@gigi](https://boards.straightdope.com/u/gigi)\ **Post date:** [September 29, 2009, 6:11pm UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360/26 "2009-09-29T18:11:47Z")
> [@Cliffy](#): > > Sounds to me like they were identical twins, though. Fraternal twins have their own placentas and blood supply, because those structures are formed from the fertilized egg. :smack: Of course you’re right. ---
**Author:** ![Broomstick](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/broomstick/32/246_2.png) [@Broomstick](https://boards.straightdope.com/u/Broomstick)\ **Post date:** [September 29, 2009, 10:01pm UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360/27 "2009-09-29T22:01:56Z")
> [@silvermist](#): > > 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 seem to recall hearing she had NOT taken fertility drugs. Sometimes stuff just happens with no clear cause. In actual fact, this may be more common than realized - prior to the late 20th Century we had no way to look inside the womb prior to birth or so closely determine conception dates. This might have happened rarely but regularly throughout human history and we’d never know - they wouldn’t appear any different than regular fraternal twins at birth, even with different sizes, because twins are not uncommonly of different size and weights at birth. ---
**Author:** ![elfkin477](https://avatars.discourse-cdn.com/v4/letter/e/a9a28c/32.png) [@elfkin477](https://boards.straightdope.com/u/elfkin477)\ **Post date:** [September 30, 2009, 7:13am UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360/28 "2009-09-30T07:13:29Z")
I wonder how this story will turn out. Every other time I’ve heard of this happening, it’s been revealed to be a hoax. ---
**Author:** ![velvetjones](https://avatars.discourse-cdn.com/v4/letter/v/5f9b8f/32.png) [@velvetjones](https://boards.straightdope.com/u/velvetjones)\ **Post date:** [October 1, 2009, 6:30pm UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360/29 "2009-10-01T18:30:24Z")
How are they so certain of the conception dates? I remember when I was pregnant (admittedly, more than 20 years ago) the conception date was a best guesstimate based on the estimated window of ovulation based on what I remembered being the first day of my last period. Not an exact science if you ask me. Do they do it differently now? ---
**Author:** ![Mama\_Zappa](https://avatars.discourse-cdn.com/v4/letter/m/71e660/32.png) [@Mama\_Zappa](https://boards.straightdope.com/u/Mama_Zappa)\ **Post date:** [October 1, 2009, 6:35pm UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360/30 "2009-10-01T18:35:32Z")
> [@velvetjones](#): > > How are they so certain of the conception dates? I remember when I was pregnant (admittedly, more than 20 years ago) the conception date was a best guesstimate based on the estimated window of ovulation based on what I remembered being the first day of my last period. Not an exact science if you ask me. Do they do it differently now? They do an initial estimate based on LMP of course, but also early ultrasounds are common nowaways (I had them at 6 weeks with both kids, as I’d had miscarriages and they wanted to determine viability / heartbeat). If a later ultrasound had showed 2 fetuses, well, they might argue that they simply missed one the first time, or they might say superfetation had occurred. Presumably “missed one” is far more common. They also can use the ultrasound for size estimates to try to determine gestational age, though as the pregnancy progresses, normal variation in growth patterns would make it less accurate. So an ultrasound at 5 months, showing one fetus at 20 weeks and one at 22 weeks size-wise wouldn’t prove anything. ---
**Author:** ![elfkin477](https://avatars.discourse-cdn.com/v4/letter/e/a9a28c/32.png) [@elfkin477](https://boards.straightdope.com/u/elfkin477)\ **Post date:** [October 2, 2009, 5:30pm UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360/31 "2009-10-02T17:30:52Z")
> [@gigi](#): > > I wonder if it’s possible one wombmate can consume more of the resources, somehow slowing the development of the other? Look up Twin-to-Twin Transfusion Syndrome. Nancy Grace’s kids didn’t have it because they’re not identical (m/f twins) and her daughter was half the size of the son, so even without TTTS there can be big differences between twins. ---
**Author:** ![Velma](https://avatars.discourse-cdn.com/v4/letter/v/85e7bf/32.png) [@Velma](https://boards.straightdope.com/u/Velma)\ **Post date:** [October 2, 2009, 8:06pm UTC](https://boards.straightdope.com/t/two-babies-not-twins/511360/32 "2009-10-02T20:06:27Z")
> [@velvetjones](#): > > How are they so certain of the conception dates? I remember when I was pregnant (admittedly, more than 20 years ago) the conception date was a best guesstimate based on the estimated window of ovulation based on what I remembered being the first day of my last period. Not an exact science if you ask me. Do they do it differently now? If twins are suspected (if hormone levels are higher than expected for one baby, for example) they will indeed do an early ultrasound. They are pretty accurate. In the first few weeks when there is rapid growth a difference of 2 weeks would be evident. ETA: I am guessing there was a change in hormone levels after the second egg was fertilized. That would create a hormone shift that would be different than regular twins also. [Previous page](https://boards.straightdope.com/t/two-babies-not-twins/511360.md?page=1)