It’s a wise child, they say, that knows his own father, but by the time the Human Tissue and Embryos Bill comes into force, his chances will be that bit poorer. This Bill, which will be going through Parliament in the next session, is a hair-raisingly complicated affair, involving issues like the creation of animal-human hybrids (half-hamster embryos, anyone?), research on embryos, human cloning and, for good measure, abortion (though it was never intended to be about that).

You wait ages for a chance to deal with developments in bioethics, then you get more than you can handle in one go. If the Government has sense, it will make the entire Bill a matter for free votes.

Today we got the report of the parliamentary committee that scrutinised the draft Bill, a group composed of a range of nice, decent people, from Professor Robert Winston to the Bishop of St Albans. It’s especially interesting how it deals with fathers. Formerly, being a father was a brutal matter of biology – the father begot the baby and, with a bit of luck, this fact was registered on the birth certificate. Ideally, of course, he would also do his bit to rear his child and if he didn’t, why, the Child Support Agency would be after him. Now parenthood is becoming a more nebulous affair.

One statement from the report is especially suggestive: “The draft Bill seeks to take a new approach to parenthood, moving towards the concept of parenthood as a legal responsibility rather than a biological relationship.”

What’s that meant to mean? Potentially, it is the reworking of the whole idea of a family. Can one half of a lesbian couple be named on a baby’s birth certificate as the “father” of a child? That was one scenario raised by the Bill and it still hasn't been discounted – which would make a birth certificate less a statement of fact than a record of aspiration. Is the lesbian partner of a child’s biological mother its social parent? At present, a lesbian who approaches an IVF clinic to have a baby does so as an individual; the new law will enable two lesbians to do so as a couple – a mother and a quasi-father.

Does such a woman have to have account of her prospective baby’s “need for a father”? That used to be the case by law. Now the committee says that what she actually needs to take into account is its need of a second parent. Or, as the committee put it: “We have found persuasive evidence that a loving, supportive family network is more important than the gender of the second parent . . . in an area such as this, the law has symbolic value. Ultimately, the issue is one of what is in the best interests of the child.”

Well, quite so, but most of us would instinctively feel – from a combination of common sense, biology and tradition – that a parent of each sex is precisely what is in the child’s best interests. Of course, the existing provision that women wanting an IVF baby should have to consider the child’s need for a father is largely a matter of form. It hasn’t stopped lesbians becoming mothers but at least it recorded that a father was necessary for a child. It seems extraordinary that at a time when it has never been easier to establish through DNA testing who is the biological father of a child, we’ve turned the whole concept of fatherhood into something abstract and unimportant.

On the credit side, one excellent aspect of the report is that it recommends that birth certificates should record that a child was conceived from donor sperm. In that way, the State will not be party to a deception – at some point, these children will know how they came into being and at the age of 18 in any case they will have the right to approach the donors of sperm to ask whether they can meet up.

Biology is fundamental to our sense of who we are. My own father was adopted when he was a day old and adored his parents but he was always curious about his natural parentage – all he ever got to know was that his natural mother’s husband was not his father. Tom Ellis, a donor-conceived man who appeared before the committee, argued that the partner of a child’s natural mother or father should not be referred to as its parent, but as an “adoptive” or “step” parent. That’s truthful, unlike most things to do with IVF.

Can’t we just say it: that a child flourishes best when it has a parent of each sex, better than if both parents are the same sex? I’m equally persuaded that a mother is necessary for a child’s wellbeing. And mothers, like fathers, could yet be optional. Even with great strides in IVF we’re still limited by biology to the extent that we need an egg from a mother and a sperm from a father in order to produce an embryo, which will have to be implanted in a woman’s womb. The time, however, isn’t be far off, when those constraints will seem quaint.

In the next half century, we will have the means to make artificial wombs. More importantly, we will be able to fiddle with sperm and egg cells in order to make it possible for two gay men or two lesbian women to be both the genetic parents of a baby. The committee refers to this distant scenario by insisting that “if the technology became available to create an embryo only from the genetic material of two women without the need for fertilisation by a sperm, any question of whether such an embryo should be allowed to be inserted into a woman should be a matter for Parliament to decide”. If? When, more like.

Of course, the obvious objection to all these concerns is that there’s nothing we can do about them. If these developments don’t happen here, why, they will happen somewhere else. True, but as the committee points out, the State is involved, whether we like it or not, in what happens in IVF clinics. It funds treatments; it helps to fund the research. The State has to act, if you like, as the prospective child’s guardian, a protector against the destructive whims of people hell-bent on becoming parents at whatever cost to the potential baby. That includes, I think, protecting that baby’s need for a father. And a mother.

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