You'd think it was Christmas. Elisa has thought and talked about nothing else than our big Wednesday morning plans -- the 20-week ultrasound.

This is the big one -- the one where we can see a baby that actually looks like a baby. Chances are (and I've got my fingers crossed) that we won't have a lizard-boy-looking creature in Elisa's womb any more (the last ultrasound was creepy -- the baby actually hissed at us!). It's likely evolved past that point.

But we won't be counting toes or fingers, we'll be staring squarely at that baby's groin area. We'll be looking for that particular sign that will tell us whether Elisa will be giving birth to Aristotle or Elisandra (hint: it's a penis). We'll be transfixed. I don't think we'll notice if the baby has three arms and two heads, until we can ascertain, for sure, that we can't tell what sex the baby is.

And we won't ask for help.

We've actually gone back and forth on this, but ultimately, we're determined to save the surprise for November 10 (or thereabouts). This is a big step for Elisa. A few years ago, while we were both at Boston University, my mother sent me Christmas presents. They arrived a few weeks early, and I stacked the two or three wrapped gifts in a corner of the room. It almost killed Elisa (the paramedics had to revive her). Every day Elisa would beg me to open the presents: "I won't tell your mother you opened them!" or "Open them already before I stab you with this rusty pen!" Calmly, I waited for Christmas Day before opening the presents. Our relationship barely survived that trauma.

It's so bad with Elisa that I can't tell her when I buy her a present. She'll pester me to death and turn our house inside out trying to find out what I have bought her.

And now this surprise -- the biggest one of both our lives -- will somehow remain secret. How? Reverse psychology. I said, "I bet you can't keep it a secret."

"Yeah I can", she said.

My response was a very calm, a very cool, "prove it". So Elisa is between a rock and a hard place -- find out the sex of the baby and lose her bet with me, or win the bet but have to wait four more months to unwrap this present.

It's killing her. There's a reason why she's used every Old Wive's Tale in the book to try and divine the baby's sex. And now she'll be so close, SO close to the answer, and -- well, I don't know what she'll do. I bet she's hoping our baby has a really big penis so there's no mystery.

The pressure is intense for us to learn the baby's sex. Our best friends here in Berkeley are having a baby as well, lagging Elisa by two weeks. But they're doing their 20-week ultrasound tomorrow as well, and tomorrow night they'll know their baby's sex. Elisa's friends want to know for baby-shower purposes (blue or pink).

But I want to savor this experience, and I feel that knowing the baby's sex somehow shortchanges it. The vast majority of expectant parents would beg to differ, and I respect them for it, but for me, this is important. I don't want to know who won this game, the X or Y chromosome, before it's over. I don't want anyone spoiling the end of this movie for me.

I don't want any more lame metaphors that say the same thing: I'm waiting until November.