Totally agree with peeples, keeping a loving relationship after kids may need some planning and postponing and work, but is totally possible.
Kids are a joy, and if the couple lives parenthood positively, all the sacrifices are bearable.
It gets easier when you have family nearby willing to babysit - you can have dates without spending a fortune for babysitter and getting out - you can actually say in ;).
Anyway my answer is yes, the romance after kids is possible (I even wrote a hub about it) but it's not easy peasy. It requires dedication.
And if there are already problems within the couple, having kids makes it harder.