As a generalization it's usually better, tax wise, for a married couple to file jointly as opposed to filing separately. That's because of restrictions imposed on married couples who do file separately. You can read about the advantages and disadvantages of the two filing methods here: https://turbotax.intuit.com/tax-tools/tax-tips/IRS-Tax-Return/Should-You-and-Your-Spouse-File-Taxes-...
The article does point out that there can be occasions where filing separately is better from a tax perspective and one of those occasions does involve large out of pocket expenses for medical bills.
If you are really using a desktop version of TurboTax you can make the determination easily: simply prepare 3 income tax returns, one for joint filing and 2 for each spouse filing separately. Then actually file the joint or 2 separate income tax returns depending on which method works best. (If you use "online" TurboTax you need to use 3 different accounts to achieve this comparison as each online account is good for only one income tax return. You can then abandon the income tax return or returns that you don't use.)
Tom Young