It's interesting that pregnancy has opened your eyes to problems that were there all along. Many people say that they suddenly feel differently about their stepkids once they have their own, but in this case, you've suddenly become more honest with yourself about the problems that exist in your marriage.  I don't know if that's hormonal, or because you now have another life to protect, or what.

It's unlikely, it seems to me, that you will be able to put the blinders back on. Now would be the time to start setting limits and addressing these issues with your DH, but prepare to meet a lot of resistance, since you seemed okay with these issues before. But that doesn't mean you shouldn't address the issues.

Like tog says, the pregnancy has caused you to remove the blinders.  Big things like this have a habit of making us reevaluate our lives.   Time to have some frank conversations with your DH. 

I think when you are pregnant too, huge maternal instincts kick in about protecting your own child.  And, I’m even talking about DNA kicking in going way back when.  When you look at the mammal world, for instance, there are many critters who will just take off to avoid trouble.  But, if they are mammas with babies, they’ll fight to the bitter end to protect their own.  Given that, these feelings are very natural.

Where the issue comes in for some SMs, however, is that they may find themselves pregnant in a less-than-ideal family situation.  Sure, lazy husbands can be out and about everywhere.  However, lazy and uncooperative children and ones not the fruit of your loins, generally only exist in step-situations.  Because these SKs are children, it gets tricky for a SM.  You hear all the time about how SMs favor their own kids over the SKs.  People just seem to assume that SM is a be.atch whenever this occurs.  They don’t stop to think that a) SM as a mom is just feeling/ doing what every other mom does, b) young children, particularly infants always get more attention, and c) we’re talking about natural maternal instincts here, a million plus years of DNA kicking in.

So, I think your feelings are very natural.  As adults we can make decisions for ourselves to stay in difficult situations; however, for mothers in particular, it is quite a different story “forcing” that decision on children.  Yep!  Have a Coming to Jesus discussion with your DH.  Ideally, you’d want to bring everyone around on this and have your DH and SS feel a part of the birth of this child.  But that is yet again, putting the bulk of the burden on SM.  What usually winds up happening, is SM starts to disengage and focus on her own children.  Which, yes, that probably going to garner her the Evil SM label from her SS, but on the other hand, we are talking about a million plus years of DNA here vs. an unruly child whose own father won’t own up to.

It's always hard with children, because obviously they are innocent.  And, everyone always seems to think that SM is supposed to somehow be able to turn her SKs around and make everything hunky-dory for all in the family.  I’m more realistic, and see all of the stereotypes and sexism and archaic thinking that goes into putting all of this pressure on SM.  I see SKs as their mom and dad’s children and a by-product of mom and dad’s environment and choices.  It is not a SM’s responsibility to clean up a familial mess that was put into place, more than likely, long before she came along.  A SM’s own maternal instincts are going to be way more powerful than any “obligation” she may feel to clean up another family’s disaster not of her own creation.

That if DH was this great husband, friend, partner, parent.  He would still be with BM.  Living the happy family.   There are reasons that that marriage failed.   Reasons not talked about .  
You are seeing the real DH. He not going to change 

It normally takes many years to start seeing that.  You have to make sure you parent your own child. He is not going to do it. 

I'm in a very similar situation. Pregnant with my first, married for 7 years, tween step daughter. I have definately had some mood issues. Personally I am atributing the mood changes that pass in less than a day to hormones. The reasons for my changing moods as others have said are certainly not imagined but it does feel like I am less able to cope with issues that were there before or legitimate worries about a new baby. When the hormones are surging I feel like I cannot contain my emotions over it and they overwhelm me to some extent and come out somehow in beign extra snappy or even tears and depressed moments. 

All that is to say, as others have above, the issues you are spotting now are most likely not a figment of changing hormones but real issues that you had the ability to ignore up until now. I would wait until you feel calm and in control and start conversations with your husband about how you want to be treated during pregnancy and how you would like life to look for your family once the baby arrives. Try to work together to make this work given the circumstances that you are in. 

As for your step son being called a big brother that is a pretty usual response for outsiders to try to help siblings feel included in a pregnancy and accept a new sibling. Your step son will be a big brother, so it is not untrue. It might be worth contemplating for a while why these comments disturb you and what your real concerns are. 

The problems have always been there, but maybe now that you sense the problems may negatively impact YOUR child there is more concern. 

I believe that you're just really concerned and you want all the best for your future child, it happens naturally, as guys above have mentioned, however I think that you need to explain to your husband and your ss that now it's gonna be difficult to deal with everything on your own, you need help and care. Moreover, just talk to your husband honestly and say what exactly bothers you. He will reanalize his behavior, I suppose

I'm also pregnant with my first. Sd14. I can't even stand her anymore. So lazy and messy. I feel like I'm just so done w all of her crap. She's wanting attention and she's jealous of the stuff we're doing /getting for the baby. I want to say oh u just wait!!!! 

I am pregnant with my first and have DS11(use to be SS). My situation is a little different but I will say hormones play alot into everything you are feeling. At this point just like me your focus is on having this baby and bringing them into a very happy stable home. All normal. My DH who I love very much has been annoying me with some of the things he does. I for the last few years have done more parenting of DS 11 but I am forcing him to do more as I just do not have the energy anymore.

DS behavior has also changed and we have had to go to therapy to work through a lot of things for him self and as a family. I will say I am was on edge with him lately because I can never tell anymore if we are going to argue over the dumbest things or if he is going to have smart mouth. I am having a hard time compared to normal keeping my cool.

If you are feeling this way you need to have a serious talk with your DH about everything and force him to do more. If not you will still feel this way after baby and it will probably be much worse if you feel you are not getting the help you need from him or the support.

The last one about congratulating on being a big brother well reality is he is going to be. You may see a different side of it but they are still related and share the same dad. While it is normal that DH has been through this before and you are feeling you do not get to have those first with him you really need to put that in its place. You knew this when you got married and when you two decided to have a baby. You need to spin it and put a different perspective on it. This is your first together. It will be different as you are a different person. No matter what every child is different every baby is different no two humans are alike. He has been through the experience but the he has for you are different and the emotions he will have for this baby will be new for him as it is a new child.

Best of luck.

I am with you 100%! I feel though you have a DH problem more than SK. I am also expecting in April. There will be almost 11 years between SD and our baby. SK also struggles with the exact same things... lazy, entitled, self-centered, bratty, rude... etc. The list goes on! I think the difference though here is that I have been fortunate enough the my DH has "seen the light" when it comes to his daughter now. No longer does he live in denial. He knows she is lazy, unhygenic and manipulative. He knows she is incredibly rude and talks back. He lets her spend extra time at her BM because in his exact words "She is just like her mother." He knows that she just makes everything more difficult when she's around and more stressful for everyone involved. Of course he loves her, but he no longer views her as an innocent sweet angel. For this I am very thankful!

When DH had his daughter with BM, they went to the court house when they found out she was pregnant. He then deployed to Afghanistan and returned 8 months later when she was born... home for two weeks, then deployed right back. At not even 2 years old, he filed for divorce because she was cheating. I think my situation is different though, because DH truly wasn't around. No doctor's appointments with her, no nursery decorating, etc. This is the first time he's been able to do that stuff. He is also THRILLED it's a boy. Our first child and his first boy. So there is a "first" for both of us. Sounds weird to some placing so much emphasis on the gender... but in step parent world I think people get it. Especially when almost EVERYTHING else we are "second" to. 

I also find my self wanting to "protect" our baby. I don't want her negative energy, talking back, etc. to even be in his presence. I also find it uncomfortable when people say "Congrats to ____ on being a big sister!" "How is ____ taking all of this?" SD10 wants NOTHING to do with her little brother and I am MORE than okay with that. She says thinks like "He will be annoying. I don't want to share my bathroom with him. It's not my job to read to him! I don't want a brother. I don't want him taking attention." etc. etc. etc. SD is treated like a BFF when she goes to BM house. It's just the two of them. I have a gut feeling that when the baby gets here SD will be spending more time at her mom's. If that's how your SK truly feels, I bet the same will happen with you, especially if your DH doesn't enforce a schedule.