John Councilman, president of AMC Mortgage, says any leave of absence often prevents a person from obtaining a mortgage.

Expectant parents shopping for a home are not the only ones concerned about the date of the baby’s arrival.

Mortgage lenders are taking a harder look at prospective borrowers whose incomes have temporarily fallen while they are on leave, including new parents at home taking care of a baby. Even if a parent plans on returning to work within weeks, some lenders are balking at approving the loans.

“If you are not back at work, it’s a huge problem,” said Rick Cason, owner of Integrity Mortgage, a mortgage firm in Orlando, Fla. “Banks only deal in guaranteed income these days. It makes sense, but the guidelines are sometimes actually harsher than they need to be.”

Back in the days of easy credit, lenders were more likely to overlook the fact that a parent was out on maternity or paternity leave.

But now that lenders have become more conservative, they are requiring new parents to jump through more hoops to prove their income will be enough to cover the mortgage.

So before some prospective parents start spending their Sundays at open houses, they should be prepared to deal with some complications. They may have to delay the purchase, deal with the banks’ bureaucracy (and requests for extra paperwork) or buy a home they can afford on one salary.

“Maternity leave or any other leave of absence often prevents a person from obtaining a mortgage,” said John Councilman, president of AMC Mortgage in Fallston, Md. “There are some who long for the days when such strict proof of income was not required.”

The lenders’ new attitude can be traced, in part, to new loan quality-control measures that went into effect earlier this year. Fannie Mae and Freddie Mac, the two quasi-governmental mortgage giants that buy the bulk of conventional loans from lenders, have not changed their rules for qualifying for a mortgage. But the system of checks and balances has been tightened, making lenders increasingly skittish.

Fannie, for instance, now requires lenders to recheck a borrower’s financial situation right before the loan closes. That includes calling an employer to verify employment. Before, lenders required only a statement in writing. Fannie’s new rules went into effect on June 1. Freddie’s similar rule took effect in January.

Both Fannie and Freddie have always required that borrowers have enough income to pay for the loan on closing day — and the lender must document that the income is likely to continue for at least three years.

But here is how some lenders are interpreting the guidelines for, say, a new mother receiving short-term disability insurance for a couple of months (new mothers may receive disability payments while on maternity leave, though the amount and length depend on state law and company policies).

Since the disability payments will not continue for three years, these lenders will not count it as qualifying income, brokers said, and will require the new mother to reapply for the mortgage once she returns to work. (The same logic may apply to an injured employee receiving worker’s compensation.)

Janis Smith, a spokeswoman for Fannie Mae, said there was nothing in its guidelines that would prohibit a borrower on maternity or paternity leave from qualifying for a mortgage, as long as the borrower had proof at the time of the closing that his or her income would be adequate upon returning to work. Letters from a doctor (with a return date) and the employer (stating the return date and salary) should be enough, she added.

Loans backed by the Federal Housing Administration follow a similar protocol. Brad German, a spokesman for Freddie, said its guidelines required underwriters to make sure the borrower’s income was stable and could be expected to continue for at least three years.

But, brokers said, many lenders are clearly reading those guidelines through an increasingly conservative lens.

“Lenders are picking and choosing what part of the Freddie and Fannie guidelines they want to use and how they will interpret them because one bad loan could put a company out of business,” said Jeffrey Jaye, president of the Upfront Mortgage Brokers Association, a trade group for brokers who disclose their fees upfront.

For some lenders, that may mean approving a loan only after the borrower is back at work. “There is no real assurance that the new mom will come back to work after she has the baby,” said Marc Savitt, president of the Mortgage Center, a brokerage in Martinsburg, W.Va. “It’s just prudent underwriting to go ahead and approve the loan, but she has to be back before closing.” (Lenders cannot ask a woman if she is pregnant, brokers said, but they can ask borrowers if they expect their employment or income situation to change.)

Indeed, if Fannie or Freddie learn that a loan does not meet its underwriting requirements, it can require the lender to repurchase the loan. Both companies are performing more quality control checks on the loans they buy or package and sell as securities. And, perhaps not surprisingly, the number of repurchase requests has risen sharply.