How long to take off for baby? Couples can't agree

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The cost of raising a child is nothing to sneeze at, but for many expecting couples, it's the financial consequences of maternity leave that have them rattled.

How soon to go back to work for additional income is the top fight pregnant women have with their spouse, according to a new NerdWallet survey of 604 pregnant women and 613 mothers with teenage children. Among the women surveyed, 31 percent of pregnant women and 30 percent of experienced moms cited it as their most frequent fight. Other common fights revolved around related issues such as whether to leave work to spend more time with the child (18 percent of expectant moms and 17 percent of experienced moms) and the cost of child care (14 percent of moms in each category).

"Having a baby is a wonderful event," said certified financial planner Harriet J. Brackey, co-chief investment officer of GSK Wealth Advisors in South Florida. "Being pinched for money at the same time isn't exactly what you want."

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As a result, duration of maternity leave is also the topic most pregnant women want to know more about, with 49 percent having questions pertaining to either staying at home or going back to work immediately, according to NerdWallet. A little more than a quarter of experienced moms said they wished that as a new parent, they'd received advice "to stay home as long as they can with their child," while 6 percent said they wish they'd been told to head back to work ASAP.

The good news if you're expecting? You've got several months' notice to figure things out and make a few financial changes that could make the decision easier.

Start by exploring policies to see how long you can stay home on paid leave, said Brackey. U.S. law doesn't require employers to offer paid maternity leave, although under the Family and Medical Leave Act, eligible employees are entitled to 12 work-weeks of unpaid, job-protected leave to care for a newborn child. It's common for workers to cobble together paid leave through a combination of short-term disability policies, paid time off from the company and unused vacation days, she said. Three states—California, New Jersey and Rhode Island—also provide for some paid family leave for residents.

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Then take a hard look at your budget. "Are both salaries important to cover all the expenses?" asked certified financial planner Victoria Fillet, founder of Blueprint Financial Planning in Hoboken, N.J. That answer, and your ability to sock away extra cash as a "maternity emergency fund," will be key factors in how much unpaid time off you can afford to take, she said. Resist the urge to have your regular emergency fund do double duty for maternity leave savings, she added—that way, other unexpected financial expenses like car repairs or health care won't force you back to work earlier than expected.

Reduce what expenses you can now so that living off that reduced income won't be such a jolt after giving birth, said Elizabeth Scheiderer, a certified financial planner with NCA Financial Planners in Cleveland. "You don't want to stay home at a rate of 19 percent on your credit card," she said.

If you'll give birth before the end of the calendar year, file a new W-4 with your employer's payroll department now to increase your number of personal allowances, said Brackey. Baby does mean extra tax breaks. Making the adjustment ahead of time will mean a smaller refund come filing time, but more money in your paycheck now—when you can set it aside for savings.

Bear in mind when considering expenses that the baby will bring his or her share of new costs, some of them harder to estimate than others. "You won't go out as much, but now you have diapers and baby food," said Fillet. Plus health care and college savings, among others. Depending on the income of the family, costs for baby's first year range from $9,480 to $21,430, according to the U.S. Department of Agriculture's Expenditures on Children by Families report released in 2014.

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Costs of child care can complicate plans further. Child care fees vary widely, with residents in Mississippi paying an average $5,496 per year and those in Massachusetts paying an average $16,549, according to a 2014 Child Care Aware America report. The cost to send an infant to day care is higher than the cost of in-state college tuition and fees in 31 states, they found.

Researching those costs in advance can help you plan, Fillet said. High costs could be a reason to head back to work sooner, or to stay home longer. "Get creative, innovative," she said. If both spouses get some paid leave, switching off that time can help delay that expense. So can contributing to a pretax flexible spending account for child care. You might also explore options to reduce your day care needs, such as free child care help (hi, grandma!) or a partial work-from-home arrangement with your boss.

If you're leaning toward staying home for an extended period, weigh the full costs of doing so, said Scheiderer. Yes, you'll be saving money on child care, but the financial loss is more than your salary—you won't get an employer match on your retirement savings or be making contributions toward your Social Security benefits.