Although there is no narration or tradition to forbid a woman from breastfeeding her child while she is in the state of ritual impurity (i.e. janabat), it is better for her to avoid breastfeeding it insofar as she has not performed ghusl. Those women who attached importance to educating and proper upbringing of their children made sure to breastfeed their children in the state of ritual purity or even in the state of wudhu. There are instances of successful men and women whose mothers have said to have never breastfed their children without wudhu (minor ablution).
Hence, as is the apparent cleanness of things including the milk is important and effective on the child's health, so is the external purity (wudhu and ghusl) which should not be neglected. 
Also, there is no problem in having sexual intercourse with one's spouse in a room in which there is a child, if the child is not discerning (mumayyiz). However, if the child is awake, having sexual intercourse close to it or in the same in which the child is sleeping is abominable and disapproved (makrooh). It has been narrated that: "If a woman and a man have sexual intercourse near a wakeful child, this will lead the child to become an adulterer in future."[1] There is no doubt that what has been stated in these narrations do not necessarily imply perfect causality and a universal rule. That is to say it is not true to say that all children who have been breastfed while their mothers have been in the state of ritual impurity will end up becoming adulterers. In fact, it means that ritual impurity can be a precursor to moral deviations and one should not allow such a precursor (or preliminary) to come into being. On the other hand, if parents have conjugal relationships at a place where there are no children, it does not mean that they won't fall into error of any kind but they are, of course, less likely to commit such sins.
It is therefore very appropriate for parents not to have sexual intercourse even in the presence of their breastfeeding children.

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