O- Blood type.

[AshleyMorgan]

So, when I went for my seven week ultra sound, i found out that i have a O- blood type. They told me that i have to get some kind of shot at 23 weeks. What exactly is this shot for? I'm confused and kinda scared!

Also, how likely is the posibility of being a few weeks farther along than what they tell you? In my last ultra sound i was 6w6days. I posted some pictures. But i saw the heart beat! I feel like i might be a tad bit father along than they think. The baby is 7.7cm now!

[MissmyAngel]

cocacolapanda is right. They give you the shot, because if your baby happens to have a + blood type, your immune system can attack the baby's during birth. The shot prevents your blood from doing that. It is really important to get the shot if you are unsure, because if you dont, your body will become sensitized to the shot for life.

[cocacolapanda]

I'm also 0-, it ***** as you can only get 0- blood, yet you can donate your blood to anyone.  As for the pregnancy thing, if you have any spotting before you get your Rogam shot you need to see the dr with in 72 hours and get a shot (I learned this with my miscarriage last pregnancy).  They give you a shot at the 23 weeks to help so there are no issues with birth, then when you deliver if your baby has positive blood you need another shot with in 72 hours of labor.

Now if the father of the baby also has negative blood it's impossible for the baby to have positive blood so the shots aren't necessary, but if your not 100% positive don't turn down the shot.

AND make sure they give it to you in the but, not the arm!  

As far as being off by a week or two, it's hard to say, it's possible if you have irregular periods, or had a late/long cycle.  

[alaysha]

I was wondering the same thing since your blood is separated from the baby so it shouldn't be an issue what your blood type is unless your rh negative.

[claud9]

Are you O rh negative? Is that why they are giving you the shot?

[alaysha]

At this stage in pregnancy it is impossible to be a couple weeks off. In the first 13 weeks of pregnancy all babies develop at the exact same rate. That is why the use early ultrasounds for dating purposes. After 13 weeks babies start developing at their own rate and then they can measure a couple weeks either way. But if you have 2 ultrasounds that are saying the same thing then that is how far along you are. Congrats on your pregnancy! I was 19 the first time I got pregnant and she is the light of my life! :)

[AshleyMorgan]

I do not know if the length of my baby is correct. On the ultrasound it says 1.0/7.7cm/36Hz
i guess that is the size of the baby? or idk.