Is it permissible for a wife to leave her house without obtaining the permission of her husband, and not to come back unless he divorces her co-wife?

It is forbidden for the wife to leave without obtaining her husband`s permission, and it is impermissible for her to ask him to divorce her co-wife as this inflicts harm on the latter and such an act is forbidden in Islamic law.

Is it a condition that the meat of the Eid sacrifice should be distributed in order for the sacrifice to be accepted by Allah?

The poor and needy should be given from that sacrifice , even if it be a small portion,(One kilo for example) as raw meat so that they would cook it the way they want. The remainder of that sacrifice is either distributed, eaten, or offered to people in a banquette .

Is prayer nullified by having thoughts while performing it?

Prayer isn`t nullified by having thoughts while performing it, provided that the praying person offers all of its pillars and meets all of its conditions. However, the reward decreases significantly in the absence of reverence since a praying person is rewarded according to the attentiveness of his/her heart during prayer.

I am pregnant with four twins since two months although I didn't have childbearing potential during the last four years. In addition, the doctor specialized in reprusccusions, already has notified me about the possible reprusccusions as a result of being pregnant with four twins as follows: abortion, Metrorrhagia, Premature birth, high blood pressure, gestational diabetes and the like. What is the ruling on aborting some of the aforementioned embryos? A medical report was attached in which the status of my question is clarified.