If this is a normal part of her job, they can certainly require it. If she is not able to fulfill the full job requirement, they do not have to treat her in any special way, they have the right to terminate her and hire someone who CAN do the full job.

I have to comment to jaydey: Yes, if a person becomes pregnant, in 99.9% of cases, it IS their fault, their choice. People have known for hundreds of years how to avoid pregnancy, if they choose to do so it IS their own responsibility (both parents)
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So…she wants someone else to do her share of the work? Is that it?? It WAS her choice to have a baby, and i assume she is a single mother?? What with having nobody to look after the baby at night??? She was foolish to take on motherhood when she was not in a stable relationship. Its not for the co-workers to pick up her slack.
EDIT: Its the truth Jaydee, If i choose to suddenly go on holiday, should all teh mothers who have had to stay at home for their kids have to come in to work to cover me?? If im hung-over because i chose to get drunk, should the parents who had to stay sobre have to come in to cover me?? Why should i suddenly have to enable these women to have babies if its THEIR choice???? Its not MY job to help them!! THEY wanted kids, they knew life would be hard, but they still did it.
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I think theyre allowed but its not right at all! I thinks its insensitive

and milky-joe thats a horrible thing to say and there are all sorts of reaosns why she could be a mother, sometimes accidents happen or maybe her relationship status changed during the pregnancy or maybe she has a partner but he cant look after the baby, if she got pregnant that isnt her fault and once someone is pregnant they cant do anything about it, i hope you never have children milky-joe if thats how you think about it
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If that’s a condition for everyone then she can’t be given preferential treatment. The onus is on her to fulfill her contractual obligations and organise child care. There was a time when I had to reduce my hours and therefore my income when I was bringing up my son. I didn’t bleat about not having someone to care for him because the responsibility was mine. Now I hear women whining about this problem and that rather than planning ahead for all contingencies. If you’re her friend you could offer to help out couldn’t you?
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