Accuracy of ultrasound sex determination??

[kennedy]

Hi all,

I'm currently 24 weeks pregnant with my second child. At my 20 week anatomy scan, I was told that we were having another girl. I asked the tech how certain she was and she said that, while there are never any guarantees, she did see the infamous three white lines that typically indicate female genitalia. Having heard and read countless anecdotes of people who were told the wrong sex at their ultrasound, I'm wondering how confident I should be that I am in fact having a girl. I realize a lot depends on the sonographer's level of experience and the position on the baby, but how confident do/did others feel in what they were told at their anatomy scan? Thanks in advance for any feedback!

 

[Mara]

We were told at 12w and 15w we were having a boy and an amnio reported a boy. We also saw the genitalia at 15w pretty clearly.

If you are unsure and want more data points, what about having a 3D ultrasound around 30w? You should be able to see things pretty clearly at that point (well if the baby cooperates!!).

 

[qtiekiki]

With my first child, we were told that we were having a girl at the 20 weeks anatomy scan by the tech and again at around 28 weeks by my OB. When the tech told us it was girl, we didn't have any doubts. No doubts because it was our first, and it doesn't matter what gender she was. Basically we didn't even think to doubt it. With our second, I was told it was a boy. My DH wanted to be surprised, so the tech pull the curtain to keep him from seeing the monitor when she was checking in that area. She, then, wrote "boy?", then "girl", and then confirmed with a "boy". I was not confident that I was having a boy. I think it was because I knew DH and his parents wanted a boy. That pressure kind of made me think that I am just not going to get what they wanted, and that I didn't want to get their hope up, even though they were going to be surprised. I actually asked my OB to confirm on the gender. When he told me at 28 weeks that it is indeed a boy, I had no doubt. I ended up telling DH the gender.

I don't think our story and our confident level with our techs will change how you feel. You probably don't have confident with your tech because you wanted to hear the opposite of what you were told (I am assuming). I had heard of wrong gender guesses, so they are possible. I second Mara's suggestion of an elective u/s, or ask your OB to confirm on gender if your OB has a u/s machine in his office.

 

[cara]

At what age gestation, how good a look did the person get, and what are their qualifications? Well trained people that get a good look at 14 weeks gestation are 95+% accurate. Cant remember the exact percentage, but its high, they have done a study. The wrong predictions usually happen when someone gets a marginal-quality look at earlier gestation and isn't well-trained enough to know what they are looking at or that they didn't get the greatest look and/or for some reason doesn't convey their uncertainty etc. to the parents. (Including the possibility that the person *tried* to convey their uncertainty to the parents, but that didn't get heard after the boy/girl part of the information!)

At 19 weeks, my ultrasound tech wouldn't say the word (she was not authorized to tell you anything), but she lined it all up on the screen and said, "Looks clear to me, what do you think?" And it was pretty clear we had a boy on our hands.

I personally would want to see it for myself, but if a sonographer told me at a 20 week scan that they saw the three lines, I think that's pretty strong for team pink.

 

[kennedy]

Mara and Qtiekiki-- Thanks for your replies. It's helpful to hear that they got it right!

I should have said in my original post that I won't be getting any more ultrasounds assuming all continues to go well (knock wood!). As much as I would like to know for certain that I'm having a girl, I wouldn't feel right getting another ultrasound just to satisfy my curiosity. There seems to be some doubt about the absolute safety of ultrasound use in pregnancy, so I don't want to expose my baby to more than is medically necessary.

By the way, I'm actually hoping that the tech is right as I very much want another girl....but of course must add that what I want most of all is a healthy baby.

 

[kennedy]

At what age gestation, how good a look did the person get, and what are their qualifications? Well trained people that get a good look at 14 weeks gestation are 95+% accurate. Cant remember the exact percentage, but its high, they have done a study. The wrong predictions usually happen when someone gets a marginal-quality look at earlier gestation and isn't well-trained enough to know what they are looking at or that they didn't get the greatest look and/or for some reason doesn't convey their uncertainty etc. to the parents. (Including the possibility that the person *tried* to convey their uncertainty to the parents, but that didn't get heard after the boy/girl part of the information!)

At 19 weeks, my ultrasound tech wouldn't say the word (she was not authorized to tell you anything), but she lined it all up on the screen and said, "Looks clear to me, what do you think?" And it was pretty clear we had a boy on our hands.

I personally would want to see it for myself, but if a sonographer told me at a 20 week scan that they saw the three lines, I think that's pretty strong for team pink.

Thanks, Cara, that's very helpful. I've tried looking up statistics, but haven't found anything terribly convincing.

To answer your questions, I was 20 weeks 2 days (measuring 20 weeks 5 days, if that matters) at the time of the scan. I'm not sure what the sonographer's qualifications were other than that she was working at the imaging center. I asked her how sure she was and she told me that it's impossible to be 100% certain with ultrasound, but that she saw (and showed us) the three lines that they look for when determining the baby is female. I can't say it looked like much to me, although I did see the three lines she was referring to. How experienced she is, I don't know, but it seems like she got a good look.

 

[Sha]

I was told 'girl' at our 20 week scan, and we saw the three white lines too - they were pretty clear. We did have a girl!

 

[curlygirl]

With my first, I was told girl at around 19 weeks and it was confirmed via amnio. With my 2nd, I was told girl at 15 weeks and the amnio confirmed it as well so I think it's safe to say you are having another girl. Congratulations!!!

 

[taovandel]

I was told girl at 20 week anatomy scan....then boy at 24 week ultrasound. Super fun! haha. We did in fact have a little boy.


This time around I was told girl from the get go and every u/s since she has remained a she.

 

[MichelleCarmen]

I'm pretty sure I read somewhere that if the ultrasound shows what looks like a boy, the baby for sure is a boy. Girls aren't always 100%

With my first son, I convinced the gal to check at 16 weeks and we could tell he would be a boy. With second baby, it was the same (ultrasound around 18 weeks).

If the baby appeared to be a girl, I'd probably want to confirm w/a second ultrasound. In a book I read about 10 yrs back, it said that ususally women's intuition is 97% correct re: what sex the baby is. Who knows if that's right!

 

[kennedy]

I was told girl at 20 week anatomy scan....then boy at 24 week ultrasound. Super fun! haha. We did in fact have a little boy.


This time around I was told girl from the get go and every u/s since she has remained a she.

Do you mind if I ask a quick question? When you were told girl at the 20 week anatomy scan, were they basing that on an absence of a penis or the presence of what appeared to be female genitalia (i.e. the three white lines of the labia)?

Based on other's responses, it sounds like most of the time they get it right, but I do think the margin of error is slightly larger with girls.

 

[taovandel]

She said she didn't see a penis...and then gave me what she said was a "potty" shot..meaning showed girl bits. But I really think she was basing it completely on not seeing a penis (it was blocked by the cord...) I later posted those pictures on ingender.com and they said they had no clue why the lady was so sure it was a girl based on the pictures....she said she was 98% sure it was a girl.

 

[Pandora II]

If you saw the 3 white lines then I think you can be confident that it is definitely a girl.

I think the problem comes when techs guess girl based on NOT seeing boy bits rather than on seeing the girl bits - ie a prediction based on negatives rather than positives.

We saw the 3 white lines for Daisy at 20 weeks and both sonographers said definite girl - and she was...

 

[packrat]

With London we were told girl, but the tech was going a hundred miles an hour and didn't stop and show us anything. When we asked if that was a definite answer she said no, that she had told once that a couple was having a boy but the baby was turned in such a way and wouldn't move, that it just looked like a boy. We did neutral stuff, and the u/s was correct. (I *knew* anyway that we were having a girl). With Trapper, we had a male tech and he took his time and while we were watching the screen, it was so obvious that we were having a boy (which I knew already haha). The tech laughed and was like "There is NO mistaking this baby is a boy".

 

[NakedFinger]

my friend was told at 24 weeks that her twins were going to be two boys. Since she wanted at least one girl, and was slightly bummed she asked the tech "are you sure?". To which she received the condescending response "I've been doing this a long time, its definitely two boys".

Turns out, she had not one girl, but two girls.

 

[Sha]

my friend was told at 24 weeks that her twins were going to be two boys. Since she wanted at least one girl, and was slightly bummed she asked the tech "are you sure?". To which she received the condescending response "I've been doing this a long time, its definitely two boys".

Turns out, she had not one girl, but two girls.

Oh my! That must've been a shock! A happy shock, hopefully?

That's a lot of clothes to have to send back to the store!

 

[Dancing Fire]

not very accurate...our second daughter suppose to be a boy.

 

[qtiekiki]

Kennedy - I think you are feeling the same way I was with my second. What was your gut feeling on the gender before the u/s? With my second, I had a dream, right before I found out I was pregnant, that I gave birth to twins, one girl and one boy. A couple days later, I found out I was pregnant and I thought "oh, maybe the dream means that I am having a boy this time since I already have a daughter". That was my gut feeling, even though my feeling went back and forth between the genders throughout the pregnancy. Our minds can definitely convince us otherwise, but what do you feel without thinking about it?

DF - I think u/s had greatly improved since you had kids.

 

[Kay]

We were told our second is a girl at 15 weeks when the tech saw the "3 line sign." The amnio confirmed.

 

[janinegirly]

Our 20 wk u/s told us it was a girl. I was constantly worried it was wrong (I like 100% accuracy!) and people often stopped me in the street to say I was definitely having a boy based on how I was carrying. After she was born all I saw was a baby and a big cord and said "is it a girl???" hehe. Of course it was, thank goodness .

Kay - why did you decide on an amnio this time around? sorry for the sidebar.

 

[partgypsy]

I think it's pretty accurate. I'm sure it happens, but I don't know anyone my age or younger having children who were told an incorrect answer from the ultrasound.