In The Netherlands it's pretty normal to bring kids to daycare from 3 or 6 months.
In the end, there is often a salary hit though. My wife started working less. Also, there is no extra time anymore - on working days, we always go home at 17:00 sharp.
That's still not that huge a portion of a typical ~40 years career (unless you have a lot of children - I think the average for western Europe is somewhere between 1 and 2 kids) and you'd get parental leave payments during that time.
So sure it probably hurts your combined income but I think it's very rarely a 50% reduction as suggested by OP saying he needs to double his salary to stay at the same level.
Sources: http://www.bls.gov/emp/ep_table_303.htm and http://stats.oecd.org/Index.aspx?DatasetCode=LFS_SEXAGE_I_R
Where I come from this is extremely uncommon.