O-Negative Blood Type & Pregnancy
Berkeley Parents Network >
Pregnancy & Childbirth >
O-Negative Blood Type & Pregnancy
I just learned that I am O neg. blood type and my husband is a
positive blood type. Evidently, there is some risk that the baby
will have the positive blood type and my body will see it as a
foreign invader and attack it somehow. some shot is supposed to
take care of it. if anyone knows anything about this, i would
A mismatch in blood types can be dealt with. Is this your first
preganancy ever (i.e., no previous pregnancies that ended in
miscarriage or termination)? If it is, then all you need is a
shot of Rho-gam at a mid-point in the pregnancy and then again
after the baby is born. Rho-Gam puts TEMPORARY RH-factor anti-
bodies in the mother's blood so her body doesn't product its
own, and the next baby gets a clean slate and you start the Rho-
GAM shots over. If you've already had a pregnancy, make sure
your doctor knows, because your blood will need to be tested for
Rh-antibodies. You will still need the Rho-GAM shots for this
pregnancy, but additional monitoring of anti-bodies may be
required. The baby's blood will be typed at birth. If your
husband is carrying a recessive gene for Rh-negative, you may
end up with an Rh-negative baby anyway, in which case you won't
need the second (post-birth) Rho-GAM shot. That's what happened
to me. My ex-husband is O-positive and I'm O-negative and both
our kids are RH-negative. Rho-gam has been around since the mid-
60's, so your doctor should be aware of it. Just make sure the
doctor knows about your RH discrepancies.
My husband and I also have different RH factors. It is fairly
common, and your doctor will know when you need the Rhogam (sp)
shot, so don't worry about your body rejecting the baby. During
my first pregnancy, I believe I was given a shot at some time
during the pregnancy and again after birth- basically anytime
your blood might mix with the baby's. I miscarried once and was
given a shot after that as a precautionary measure to be sure
that my body would not reject future pregnancies. Now, I am
pregnant with number 2, and I received a shot after my
amniocentesis. I expect they will have another for me after this
baby is born.
I am O neg and my kids' father is O positive. It turns out that
my children are O positive which is no surprise given his blood
type. The shot you need is called Rogam (spelling??). I had
them in the middle of both pregnancies, at the end of the
pregnancies, and after my two miscariages. It is extremely
important you get these shots -- they are one of the wonders of
modern medicine. It seems weird that pregnancy, which people
now harp about how natural it is, naturally has this serious
potential problem for O negative women with O positive mates.
As recently as my mother's generation, O negative women
sometimes lost their babies because of the incompatible blood
type (I believe these were called ''blue babies'' because of how
they looked when they were born.) So get your shot -- it's in
the bottom by the way, but no big deal and I am a shot whimp.
You'll be getting a Rhogam shot at 28 weeks and then right after
the birth. I had the same thing. It's not a big deal, but I
understand that Rhogam contains thimerosol (mercury
preservative) so for my next baby I will ask the doctor about
that (I think there is a Canadian company that makes it without
Congratulations on your new baby!
I also have negative blood- my husband positive. Get the shot-
RH I think it's called. I did not hear any negatives about it
when I was pregnant last year nor did I read any. Good luck-
and no worries!
My mother has O- blood and I am AB+. I am also her only child. Apparently,
she had no problems carrying me to term, but she could not have any more
children *after* me (except with a partner who also had O- blood type),
because she was sensitized by her pregnancy with me. So, I don't know if you
have to have a shot of any kind the first time -- it was fine for my mom - it
might be fine for you! You might just need to consider your options if you want
a second child. Then again, I'm no doctor, so maybe my mother's experience
Best of luck!
I too have 0 negative blood and my husband was positive. If your child
is born with positive blood, you will be given a shot to prevent your
blood from being tainted for future babies. Our first child was 0 positive,
I was given the shot. I recently gave birth to our second child who is 0
negative. Our ob assured us that we had nothing to worry about (of
course I didn't entirely believe him during our first pregnancy...but now I
know I was needlessly worrying). Best of luck-
i am 0-negative as well. I got the shot a few weeks before
pregnancy and then one right after i gave birth and everything
was fine with me and my baby. i think as long as you get the
shots everything is fine. good luck with the birth!
This condition is referred to as Rh-incompatibility. It is NOT
an issue in 1st pregnancies (miscarriages & abortions do count
as pregnancies). If you are O negative they'll give you a
RhoGam shot in your 3rd trimester, or if you are getting an
amnio or CVS. In most pregnancies, mama & baby blood don't mix,
it is just a precaution.
Here is a link to more information:
http://www.babycenter.com/refcap/1480.html. It is also talked
about in pretty much all the pregnancy books.
another O neg mama
Don't worry! I am AB-negative (apparently the rarest blood type),
and have had two children. After each birth I was given a Rho-gam
shot and everything was fine. Back in the old days, having a
negative RH-factor could have been a problem for a pregnancy, but
these days it shouldn't be a worry. Just be sure you talk to your
Dr. about it, too.
I was surprised when I was pregnant to find out about this as
well. I have A- blood type and my husband is O+. I was given a
shot in, I believe, about the last month of pregnancy in case my
child had RH+ blood type. My doctor also gave me a card that
stated I was RH- and I informed the doctors and nurses about it
when I went in for labor. I was so out of it during the birth
that I'm not really sure what they did about it. It turned out
that my son is RH- so it wasn't a problem. My doctor made me
feel that it was not a huge deal. Just something they needed to
know about and deal with at the time of labor. If you're
feeling unsure, I would ask your doctor for more details about
what the possible risks are.
Good Luck with the new baby!
O negative means you need a couple of Rhogam shots during your
pregnancy. Your OB should know all about it and at what point
you need them done. I got them from my OB and it is totally
routine and standard. Get the shots, it's not a big deal.
Check out this article, it should tell you all you need to know
and if you have further quesitons you should ask your OB about it.
I am o-negative too, and pregnant with my second. It's really no
big deal anymore because of the shot your doctor told you
about. You get a shot (at the drs office) of Rhogam (sp?) at 28
weeks, then another one right after the birth of the baby
(within the first day or so), and then forget about it until you
get pregnant again. Being o-negative and pregnant used to be an
issue, but with the shot, it's not anymore. On the plus side,
blood donation centers are always excited to see you...
I am A negative and my husband is positive, and I have had 2
children. It is important that you understand the potential
problem here, because it is very important that you know you
are getting the appropriate treatment. First, this is only a
problem AFTER the placenta barrier has been broken (by
abortion, birth, amnio, or perhaps - I don't know for sure - by
miscarraige) AND the baby in question has positive blood. Once
the barrier is broken, the baby's positive blood causes your
body to produce antibodies defending itself against the
positive blood that has entered your system. (This is the same
reason why people with negative blood can only have
transfusions of negative blood and so should be regular blood
donors if they can.) It is these antibodies that will fight any
future introduction of POSITIVE blood in SUBSEQUENT pregancies.
If this were allowed to happen, these antibodies essentially
fight or ''kill'' the SUBSEQUENT baby's blood, thereby requiring
intervention to save the baby (e.g. transfusions to the unborn
baby and premature induction). The good news is that A) the
production of antibodies in the mother is completely
preventable (via a shot of Rhogam within 72 hours of the
breaking of the placenta barrier) and B) the first baby may
also be negative (so that you do not produce antibodies) and/or
the second baby may be negative (so that your body does not
fight its blood). How might your baby be negative? This may be
simplistic, but it is basically this: You get a + or a - from
each of your parents. Therefore, you and your husband, and
every person out there, either has a positive/positive
combination, a positive/negative, a negative/positive, or a
negative/negative. Because negative is recessive, only the
negative/negative combination manifests itself as negative
overall (so you must have negative/negative, but your husband
could be one of the other 3 combinations - i.e., he may CARRY a
negative to give to your babies). If he passes on a negative,
your baby will be negative. If he passes on a positive, your
baby will be positive. It is up to him. As a case in point, my
first baby was negative, but my second baby is positive. Of
course they don't know what blood type the baby is until the
baby is born. So, what do you do to monitor your care? You make
sure that you get that Rhogam shot after the amnio if you get
one and within 72 hours of the birth and you remind everyone
who will listen that you are negative. In the US, they also
give you a ''booster'' at 24 weeks or so, but in other countries
(I had my 2nd baby in France) they don't. In my experience all
of this is monitored very closely. When they told me that my
first baby was born negative so I didn't need the shot, you bet
I was wanting to see it on his chart, and that it had been
confirmed and reconfirmed, because mistakes can be made. They
won't give you the shot ''anyway just in case'' because it can
cause jaundice (rare) I understand. Anyway, make sure you get
it and be informed so you understand what the doctors are
telling you. There is no need to be worried. Good luck! E-mail
me if you would like to ask anything else.
I'm in the same situation. I was given a shot of Rhogam after an
earlier miscarriage, and am now planning to have a dose at 28
weeks, then another after childbirth. According to my OB, they
think that Rhogam is effective for at least 12 weeks in
preventing your body from becoming sensitive to Rh-positive
blood, which would only happen if the baby is Rh-positive and
your blood mixes.
Don't worry. Things are much better these days. Yes, there
is a risk, and you should mention it when you see your
doctor or any other care provider. But it's not that big a
problem now. And it's always been less of a problem witth
first babies than with subsequent pregnancies. You'll get a
couple of shots over the course of your pregnancy that will
help your body cope with your baby if he or she is Rh + .
Check with your doctor about the shots and when to take
them, and then relax and enjoy your pregnancy.
Congratulations on being the universal donor! I am Rh- (B-) also and
have had two healthy pregnancies. I was given a shot or Rhogam (sp?)
at 28 weeks pregnant with both pregnancies. With my first child, who is
Rh+, I was also given a shot of Rhogam in the hospital. The shots are
not too bad, only the location of the injection is not fun - in the rear end
(however after giving birth twice getting a shot in the bum is not big
deal). If this is your first pregnancy, you have nothing to worry about. An
Rh- mother builds antibodies that would attact a second, third, etc.
pregnancy if the first (or any other) child is Rh+. I now have two healthy
children, one AB+ and one B-, and because the second one was Rh-, I
did not have to get the shot in the hospital.
I too am an O-negative, and my husband has a positive blood
type. We have a healthy baby that was born 18 months ago. He
himself has a positive blood type too.
I remember the concern I felt when I found out what my blood
This is how it works:
First at the very early stages of the pregnancy your doctor
should check to make sure you don't have anti bodies for
positive blood type.The anti-bodies developed as a result of
contact with a positive blood type. So, if this is your first
pregnancy, there is a very slim chance that you have them,
unless you were ever given positive blood type (what are the
chances of that...) or something of a sort.
There is almost no risk to reject the baby on the first
pregnancy. That is because until the actual delivery there is no
contact between the mom's blood and her baby. Only in cases of a
major bleeding the doctor will look into it.
In our modern world, there is a great invention that is
called ''Anti D''. This vaccine shot will be given to twice during
the pregnancy: you when you reach the 28th week of your
pregnancy (at which point they will check again that you didn't
developed any anti-bodies, which you won't), and within 72 hours
of the delivery. The vaccine destroys the baby's white blood
cells before the mom's immune system can identify them and
reject them, and so no anti bodies are created. The vaccine only
lasts a few weeks though.
So basically for the first pregnancy there's little to worry
about. For your next pregnancies, you should just make sure you
get the shot on time and all will be fine.
Being a O negative, as you know, you can give blood to anyone,
but can receive only from O negative (even more specific than O
positive that can give blood to all but O negative). I often
wonder if our blood type has more indication of who we are than
we seem to think...
If you have any further questions, please feel free to email me.
I didn't notice anyone mentioning something that happened to
both me and my sister with newborn babies... We are both O- and
married positive blood husbands. We had the rhogam.. and that
is no big deal. But, both of our newborn babies were more
susceptible to newborn jaundice. In the case of my sister, she
left the hospital early (before 24 hours after the birth) and
nobody caught the jaundice (because it often doesn't kick in for
24-48 hours). Her baby had to go back to the NICU for a couple
of days because it had progressed to very high levels at home.
It was really hard for her to have to bring her baby back to the
hospital and keep it under lights when all she wanted to be
doing was bonding at home. Also, she had to pump, right when
her milk came in which was very painful. Knowing this, I stayed
longer at the hospital and we monitored our baby very closely.
She did get jaudice but we spent a lot of time with her
undressed in near a sunny window and breastfeed more than
typical (which is VERY frequent anyway with a newborn, I think I
was breast feeding about 15 hours a day for the first week!)
Anyway, I'm not a doctor so my medical understanding of this is
sketchy at best, but I did read somewhere that babies born with
incompatible blood types as their moms are more susceptible to
newborn jaundice. It's really not that big a deal, if
monitored, and hopefully you can keep low through natural
measures before it reaches elevated states.
Congrats on your baby!
Someone mentioned that Rhogam contains thimerosol
(mercury preservative), and I wanted to urge you to MAKE
SURE if you get the Rhogam shot that it does not contain
thimerosol. They might be making it only without thimerosol
now, but I'm not sure. Mercury can have a serious adverse
effect on your baby, though you may not have any idea that
it's related to the shot. We are pretty sure this happened to
our son, who has a mild neurological problem that has
nonetheless had a significant impact on our lives. I wouldn't
want him to be any different from what he is, but still, to
make life a bit easier for him, I wish I knew then what I know
now. See previous Mothering magazine articles on the
subject if you don't know what I'm talking about (some are
probably on their web site). Much of the info is in their
articles on the Mercury-Autism connection.
As a student of Biomedical Engineering, I would like to clear up a few misconceptions on this board:
1- this "blue baby" phenomenon has nothing to do with blood types A, B, AB, and O. It only concerns the + and - markers (called antigens). Only worry if the mother is - (negative) and the father is + (positive). This can be done by a simple blood test.
2- AB+ is NOT the rarest blood, but it is the 'universal acceptor' because it can take A and B and + antigens(O and - are actually a lack of antigens, and all immune systems accept 'nothing' on blood cells). O- is the 'universal donor' because it has no antigens, so it's accepted by all immune systems.
Also, the long post by Jennifer is GREAT. Read it twice.
this page was last updated: Nov 18, 2006
The opinions and statements expressed on this website
are those of parents who subscribe to the
Berkeley Parents Network.
Disclaimer & Usage for
information about using content on this website.
Copyright © 1996-2013 Berkeley Parents Network