A woman who provided ova to her lesbian partner so that the partner could bear children by means of in vitro fertilization was a parent of those children, despite her waiver relinquishing any claim to offspring born of the donation. Family Code section 7613, subdivision (b), which provides that a man is not a father if he provides semen to a physician to inseminate a woman, does not apply when a woman provides her ova to produce children who will be raised in their joint home. Here, it was undisputed that K.M. and E.G. lived together and intended to bring the children into their joint home and raise them together. Their situation does not present a true egg or sperm donation situation. K.M.’s genetic relationship with the children is evidence of a mother-child relationship under the Uniform Parentage Act. Her signed waiver did not affect the determination of parentage given the particular facts of this case.