A word about breasts.

A lot of men out there are obsessed with them, which makes pregnancy the utopian ideal for a red-blooded male, because suddenly everything revolves around them. But it’s also the worst kind of catch-22, because your wife’s boobs are so sensitive you’re not allowed to touch them. Or point at them. Or look at them. I can’t stress this enough: Do not toy with your pregnant wife’s breasts.

This notion is bleak for most of us men, and worse than that, it’s completely wrapped in guilt. We’ve got to come to terms with the fact that her breasts, while still beautiful, are no longer playthings; they have life-giving functions far beyond our childish fondling. Soon, I’ll be sharing those breasts with someone who needs them considerably more than I do.

Sarah’s chest has recently ballooned to such an unnatural size, we’ve started calling them her “porn star boobs.” If I even brush up against one of them-like I can even avoid them at this point-she yelps in agony. Her epic battles with her poor, undermatched bras are not sexy. They’re disturbing.

Last night we went out for a nice dinner with Ben and Ursina. They had been reluctant to go out, because she had been nursing Lillie every couple of hours, but they finally felt comfortable leaving the baby with a sitter. We four went to Naha, a quiet, tasteful restaurant in River North. Ursina looked miserable for most of the meal. About halfway through entrées, she disappeared to the bathroom.

“She OK?” I asked.

“Expressing,” Ben said, barely looking up between bites of his pan-seared halibut.

I had no idea what this meant, but I understood that it was some weird New Mother Stuff, and didn’t ask for further details. Like his sister, Ben has never had much use for privacy, and he explained that Ursina’s breasts had been producing so much milk that the very sound of a crying baby, whether hers or someone else’s, sent milk shooting out. When she was without her baby, the pressure twisted to such unbearable levels that the only way she could alleviate the pain was by squeezing the milk out. “That’s expressing,” Ben said, and went back to his halibut.

Before Ursina returned, Ben told us, apropos of nothing, that he had tasted Ursina’s breast milk. “It’s just always kind of there,” he said. “Eventually you start wondering what it tastes like.”

So?

“It’s sweet and viscous.”

I pushed my plate away, horrified. My sister-in-law, a woman I thought I knew, has just gotten up in the middle of her venison medallions to shoot sweet, viscous milk from her breasts into a bathroom sink. While unfathomable, this oddity also made sense in the big picture, because it helped to explain why women take so long in the bathroom: There are thousands of bizarre biological possibilities for their visits. (For men, there are only two.)

When she returned to the table, she looked a lot happier, and went back to the venison nothing had ever happened. Later that night, Sarah further dumbfounded me: when breastfeeding mothers drink alcohol, it takes about an hour to enter their breast milk, so the woman uses a breast pump-a ghastly contraption that looks like the thing the Iraqis tortured Mark Wahlberg with in Three Kings-and then throws away the alcohol-infected milk. The whole process is called “Pump and dump.”

That night was the first time I’d ever had a bad dream regarding breasts. It would not be the last.