Free β-hCG and PAPP-A levels and baby's gender

These studies are showing the link between free β-hCG and PAPP-A levels in mothers blood and baby's gender. Values tend to be higher in women pregnant with girls.
Average ( desired) value is 1 MoM.

Also NT ( nuchal translucency) and AFP can be expressed in MoMs.

If you're pregnant with a boy, those values tend to be a bit higher, but close to 1 if it's a normal, healthy pregnancy ( otherwise it could be an indicator for chromosomal issues). If you're carrying a girl, values tend to be a bit lower then 1 ( but close to 1 for the same reasons).

Those hormones are done from the blood ( 'double test') usually during the first trimester and they are interpreted with ultrasound pictures in order to show the probability that the baby might suffer chromosomal problems ( mostly trisomy 21, 18,15).

My ob/gyn orders double test only if the future mommy is older then 35 and/or u/s is indicating something might be wrong.

These studies were like the punch in the face, burying my last hope for a baby boy ( hey, I've almost convinced myself this baby can turn into a boy :sad: )

Here are the studies: The impact of fetal gender on first trimester nuchal translucency and maternal serum free β-hCG and PAPP-A MoM in normal and trisomy 21 pregnancies - Cowans - 2009 - Prenatal Diagnosis - Wiley Online Library ( The impact of fetal gender on first trimester nuchal translucency and maternal serum free β-hCG and PAPP-A MoM in normal and trisomy 21 pregnancies)
Gender impact on first trimester markers in Down syndrome screening - Larsen - 2002 - Prenatal Diagnosis - Wiley Online Library

There are more studies on this subject and they are all showing the same, unfortunately :worry:

Here are my double test results at 12 weeks 6 days:

free beta hCG: 1.21 MoM
PAPP-A: 0.96MoM
NT: 0.96 MoM

Girl, eh? :sad:

Here's the link to the study about NT values The effect of fetal gender on nuchal translucency at 10–14 weeks of gestation - Lam - 2001 - Prenatal Diagnosis - Wiley Online Library

NT for female fetuses was 0.98 MoM compared to 1.o3 MoM for male fetuses.

This is so unbelievebly exciting!!! I've found another study for the first trimester with actual values for free beta hCG and PAPP-A
http://www.fetalmedicine.com/fmf/2009_11.pdf

Free β-hCG 0.95 MoM for boys
1.09 MoM for girls

PAPP-A 0.96 MoM for boys
1.02 MoM for girls

Free β-hCG is 14.74% higher if the fetus is a girl ( considered significantly higher) and PAPP-a is 6.25% higher in girls.

Of to find AFP values for the 2nd trimester! http://yoursmiles.org/psmile/science/p0316.gif

And yes, there is a link between AFP levels ( α - fetoprotein) and baby's gender!

Reproductive factors and extreme l... [Acta Obstet Gynecol Scand. 2004] - PubMed - NCBI
Women who gave birth to a girl had AFP levels that were 5% lower than those of women who had a boy.

2nd-trimester maternal serum human chorionic gonadotropin and alpha-fetoprotein levels in male and female fetuses with Down syndrome.

I'll try to find some numbers.

Cut-off for AFP is 2-2.5 MoM

Role of fetal sex in amniotic fluid alphafetoprotein screening - Knippel - 2002 - Prenatal Diagnosis - Wiley Online Library
This is the conclusion from this study: " Adjusting the cut-off MoM to 2.5 for male and to 2.0 for female fetuses halves the false positive rate from 3.4 to 1.7% without affecting the detection rate of 95%."

I can't believe no one else finds this interesting? :confused:

Hey Z I know nothing about all this, sorry!!

Quote:

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Originally Posted by TTC5

Hey Z I know nothing about all this, sorry!!

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Oh, don't be sweeti! :)
I was so thrilled when I've found it. I'd be even more so if I was in the boy range :rofl:

If we go for no.4 :pray: my ob/gyn will have me do double and triple tests just like that bcos I'm going to be closer to grandma age lol! So I'll know very, very soon that I ( most likely) failed again.

I have read this before but I only had one NT scan and that was with DS. I never got any of my levels from the 16 week scan.

All I know is, my AFP tests were very positive for DD2 (1:19) and she was (obviously) a girl, and has no downs syndrome. The same test with my son was positive too, but just barely--1:240. He was healthy as well. This time around I got a result of 1:200, not sure if it was the same exact test--I think they said it was the quad screen? Not sure. DD1 all I know is I "passed" but not sure what the result was. I was only 30 then, so that may have helped.

Not sure of the exact levels of things and don't know what MoM is.