Have you lost your maternal instinct?

Do you think maternal instinct is an absolute instinct that every women will have after they have a child?. I saw some realities about some mother that kills their offspring in their pregnancy and other kills their newly born baby. Do you think maternal instinct really exist for all women?,do you think that certain instinct will last long?. I know the main reason they’ve killed their child because of financial problem or frustrated for being left by irresponsible man who made them pregnant. I know some mother who go through this situation but still let their child alive and even taking good care of their child despite they’re faced with this reality.

Optional question:
Do you think that maternal instinct maternal instinct could/will be worn off as time passed?(e.g. when your child has became an adult and move out from your house). What about you? (please be honest).