I think perhaps your friends and family are worrying about your fertility. I’m sure you’re aware that it declines with age. And yes to whoever said that the physical act of being pregnant is so much easier under the age of 35.
I think the biggest issues you will find to impeding your career and being a mother is a) what sort of father your partner is willing to be b) how willing you will be when baby arrives to give up primary carer roles. More women (and men) need to have these conversations before marriage and before they are trapped into depressing and possibly abusive lives.
You cannot have it all unless you have a supportive partner or some serious support from grandparents.
I have learnt a lot from studying successful men. They have supportive partners who want to be primary carers and the men themselves never get the call from school or take p/t roles. They have no parental guilt for choosing to pursue a career for the mutual benefit of their families.
It’s not always easy to share the primary parenting role with your partner, nor is it wrong to change your mind on that score, but if you end up partnering with a man who expects you to default as primary carer and be the one to take all the parental leave, then your career is much likely to suffer.
My DH and I shared parental leave with our first, then for my second I changed my mind, I just wanted to be home with them. My employer had pigeonholed me and were very clearly managing me out of the workplace. I became a sahm in my late 30s and had my last child. When going back to work I never mentioned my children and my DH became the default go to person for childcare and school. We are prioritising my career now and he is happy to do that.
So look at your partner, If you are both the ‘alpha’ type one of you is going to be disappointed. You by essence of biology will be more likely to be pushed into primary carer role because of the nature of infants and being pregnant and recovering from birth. You will be at your most vulnerable, and you will soon see how vulnerable in society new mothers are.
My DH is thankfully not an alpha career type and I joke but it’s true, is more housewife than I right now. I have absolutely no mum guilt for pursuing a career again. I am like I was at 29, I am upset I lost a decade to the patriarchy but the consolation price was my children (not all bad).