Sen. Duckworth will be penalized for taking any maternity leave

[onenote]

99. It's the same because the rule is you have to vote in person and you have to present a bill

for introduction in person.

If you aren't present for a vote, it doesn't matter why -- voluntary, involuntary absences are the same. If you can't make it because you are giving birth, or recovering from a difficult labor, or nursing your child or taking them to their first day of school or their high school graduation or their wedding or the birth of your grandchild or visiting a sick relative or attending a funeral for a parent or child or anyone else, or if you're in a coma, or you simply decided to go scuba diving or take a long lunch -- no distinctions are made. The only procedure for voting is to show up and cast your vote in person. And the only way to introduce a bill is to show up and give it to the presiding office who hands it to the clerk.

And nothing prevents a Senator from drafting a bill or signing on to someone else's bill as an original co-sponsor: you don't have to be present to do those things.