I'm not gonna rail on your husband, or get into the debate over sahm, wahm, pt working moms, or ft working moms. But something that would help ALL families, and what we should ALL do regardless of our situation, is pretty basic stuff. Know how much money you have and where it's coming from, and know how much money you spend and where it's going to. Always. I would suggest going through a few months statements and write it all out in categories. For the next month (today is perfect, day one of a new month!) write down every single thing that gets spent (don't let a coke go by without notice). You can average it all out and see where the money is going / month. Then average out all income per month. During this month, be actively working on your plan on how to cut back (you'll have an idea of this before the end of this month, because most of it is probably repetitive or habitual behavior for both of you and you'll see it while going through the last few months' statements). May 1: you have item #1--a list of your income and outgo. You have item #2--the new plan in hand (plan being a budget AND the things you're gonna try to change this). A budget is a list of all expenses you'll encounter and a realistic goal of how much you'll spend for each item listed. (NOT what you have been spending; that's item #1. As item #2, this is now the realistic goal that you should be spending). For things that may come up but you don't have a specific category on your budget list for it, that can go under "miscellanious".
At the top, take off the first 10% for tithes (IF you do that, just telling you what we do). The 2nd 10% goes to savings in a savings account. If you can't save that, then you need to figure out how to before trying for baby #2 or quitting a job, in my opinion. Once you've got that figured up and written on your budget, begin with the rest: mortgage payment, insurances, utilities, maintenances, food, gas, recreation / hobbies, etc. How much does it cost to go bowling every other weekend? I think that's fair. It can't be that much. Fishing, honestly, is not a lot of money......at least not the way we do it, lol. I would suggest he get to do a bowling or fishing trip every other week (and you do something fun and cheap for yourself), and the weekends he's not doing that, you plan for a SIMPLE, INEXPENSIVE date night for you guys. It's healthy. Just plan these things with your new goals in mind. Perhaps you can develop family-friendly hobbies and still have quality time. Develop the understanding that family stuff can be very fun. Kids love to bowl. Kids love to fish. Just tweak your interests and keep family in mind!
Now once you've got this new budget in place, it'll be great to see how the month of May turns out. Check it one day a week (Friday for me, but if you work maybe a Sunday would be better) to see if you're on track during the month. How much money did you save? Show your husband what you're doing. Tell him it's an experiment (I wouldn't mention that it's to see if you can be a sahm yet). If he's on board, cool. If not, don't let it derail you; go ahead and do the plan. When May is over and you've saved a bit, show him what you've done with your documented proof.
A few things I've done that changed things for us: first, I learned how to shop and cook. You can read other things I've written, or message me privately, for more detail on how to do the salespapers, coupons, make a menu, and do all the shopping in 1 day and stick to a BASIC menu. Some people don't feel like doing this and tell me (while crying about not having money) that they can't have a menu because what if something happens that day? Well, then it's a day that is changed. Don't be freakishly dogmatic about something or it won't work. But have a basic plan, posted, and go with it as well as you can. Sometimes I have Tuesday's dinner on Thursday, and vice versa. So what? You get the idea. I started saving about $30 every week just on groceries alone by sticking to this plan. $30/week x 50 weeks/year (Obviously Thanksgiving and Christmas are not the same as the other weeks of the year for us)......that's $1,500 a year just in food!!! Dropping my husband's cellphone plan and adding him on to me with that add a line for 9.99 thing saved us $20/month ($240/yr). Consolidating my trips to town and shopping so that I don't go back and forth to the same area all the time, but do the shopping on that side of the tracks the same day I take my son to storytime at the library and have a planned playdate with friends that same day......I've just done 3 things in one day and in the same 3 mile radius instead of making that trip 3 times in one week (gas) . Cutting off the TV when we're not actively watching, washing clothes in cold water, setting the thermostat for just 3 degrees higher and lower is gonna all save some money and not hurt your lifestyle. Seeking out free things (use the internet or a local free magazine!) to do in your community for fun instead of the same old dinner and a movie trap improves your spending habits AND you have fun changing things up a bit. There's a million ways to save money in weird little ways. I personally save probably $5-7/week in refraining from picking up a coke at the cooler by the cash register! Silly! Instead of buying individual gatorades for my husband, I can be a little green AND save some money by buying the bulk powder and mixing the water myself. Make a game of it. We don't do without anything, honestly. But we do live frugally. Sometimes we delay something we'd like to have, but we never have to do without altogether. You can do it.
After you made these lifestyle changes, you will be in a better position to know what you can and cannot afford, and if you can or cannot quit working. You can then go on to some more planning: what am I going to do to be a great sahm, and not turn into a bum? I AM a sahm, so don't freak out on me for saying that! Some women are amazing, and I just shake my head watching them. Others are totally lazy and make things hard on the rest of us, because those husbands are talking! What will you be doing when staying at home? I personally like the old "homemaker" term better than "stay at home mom" because #1 it's a JOB and #2 I so do not stay at home much at all.
Next, price things as if you were having a baby. (I think it's best to go "worst case scenario and price the formula even if you plan to breast feed) Insurance copays: what does your plan cover? Baby stuff you already have, what you may need---would you be willing to shop on craigslist.org for a lot of it? Price things and see how much it'd cost to get set up. Now pretend the baby is here: $22.50-25.97 for a thing of formula, wipes, diapers every week. Copays for wellbaby visits. Baby soaps and lotions every so often. How much money have you been saving monthly with this new budget and the new savings plan? This will help you see if you can afford a baby now, or if you need to make some more changes first. In the meantime, I would put the money you are saving into the savings account since you have no real debt to pay off. It's just a good practice. We've payed off our cars, but we still make the payments, this time to a high interest account we found. Everyone, working or not, baby or not, needs to have several months worth of living expenses saved up, so this is good practice regardless of what your husband thinks right now about you staying home.
And finally, I had worked my whole life (since 13 years old!) and when dating my husband I worked as an inspector and would put in 84-104 hours a week, no lie!!! I changed careers to get married, and the whole first year of marriage (and pregnancy---got pregnant 6 weeks after the wedding) I worked 2 jobs. 40 hours/week M-F at one job, and a retail job Sat-Sun for 12 hours/week. Honestly, we did not know I was not going to return to work after our baby was born. But here he is, beautiful, perfect, totally dependant on us, and a PREEMIE so we were a little more protective than normal. I asked my husband if it'd be ok if I didn't return to work, and he was ok with that (because we already knew our financial situation and we had the habit of living below our income). But I was well aware of the fact that this was my JOB and I made sure to make my home.....a home! Dinner on the table, lunches packed so he wasn't eating out, learning to cook and budget and all of it, the house decent (never perfect, but not embarassing if guests came over unexpectedly), the boys thriving and growing in every way. I made a weekly AND daily routine (used flylady.com to help me with the idea) to make sure everything gets done. It's all printed in a folder, that and my menu and shopping stuff, the children's lesson plans that I come up with to make sure I touch on things my preschooler needs to learn in every area, etc. It's all there and I "presented" it to my husband as if I was presenting something to a boss or a partner. It made him recognize that I take this seriously and will be a good steward of my time, and he respects that and can encourage me whole-heartedly. Another part of "the plan" I presented to him: I am currently studying now to refresh and catch up on school stuff. In the summer, I will begin going back to school; online classes, about 2 at a time (it's been 15 years!). When my youngest (4 months old) is old enough for mother's day out (about 3 yrs old) I will schedule it for days that I will spend MORE time in school. When he starts real school, I will either be finished with my own schooling and begin working, or go to school full time to finish up by the time the year is out. I'll start working then, a 7-3 shift is what I'll be looking for, so I can still be home as much as possible. I know this is probably too long. But I hope that you can utilize some of what I've mentioned (or at least it give you ideas) so you can do what you need to do in your own family and situation. Good luck!