Hi there,
Congrats.
I can sympathise a little with how you will be feeling as I am expecting baby number 2 in a couple of months.
I think for us girls this is a hard decision no matter what profession you are in, but because engineering is typically male orientated anyway, there is not the support around you that perhaps in other professions you might get. (There is no way in my comany when there are 50 males and 2 female engineers that I am in a strong position to push for subsidised day care or paid maternity leave).
I took 3 months off to have number one, and then when she was 11 weeks old I went back to work full time. This was a personal choice for a number of reasons including: I love my job (I am not a stay at home coffee group kind of girl I need more stimulation than that), the money is pretty useful (although not totally essential - we could survive on one income) and the main reason for me is my father died when I was very young, leaving my mother with 4 kids, no money, no life insurance and no job. I decided it was very important that I could support my family by myself.
My daughter gets far more stimulation and experiences in daycare than she would at home with me. Sure there are days she doesn't want me to leave her, and times I have to leave a screaming child at the window because I have an urgent meeting to go to (and although I feel rotton I know that in 2 minutes if I peak through the window she is off with her friends having a good time). Generally though, as a working mum I love daycare - to me daycare is easier than having kids at school - you drop them off at 8.00, pick them up at 5.00, whereas school is only from 9.00am until 3.00pm). My daughter's daycare arranges lots of extras like swimming lessons, haircuts etc. I am more worried what I will do when my daughter goes to school in another year.
I would recommendation having a go at working part time if your employer is willing to let you. (I am amazed the number of females I know who DEMAND that they come back part time, without even discussing this - some jobs it is not possible). This would enable you to stay in the work force such that in a few years time you can go back full time if you wish (especially since chances are you'll have more than one child so that will mean 7 or 8 years out the work force, not 5). You'll most likely not get the best and biggest projects to work on but it would keep you current and in the field. Engineering is not a field you learn (or relearn) in a couple of weeks.
Realistically, don't kid yourself that you can work from home, or undertake extensive volumes of study - the only way I can work from home typically is if my daughter is somewhere else.
When number 2 comes along, I will again take 3 months off, before returning to work fulltime. I am currectly working on some pretty big projects so I want to keep in the loop regaarding these (and there really is no one else to do so) so I hope to work a few hours a week from home.
In the end the choice has to be one you are happy with - if you want to stay at home, then do so - don't worry what other people think. As long as you and your husband and baby are happy with the way things are, forget everyone else - we all have different opinions, and you can never keep everyone happy so keep yourself happy. As I saw written somewhere, "the past is gone, the future is unknown, live for now, it is a gift, that is why it is called the present".
Enjoy your baby whichever decision you make.