A Life Worth Living ICSI: A new challenge to human life

Mar 31, 2011

As reproductive technology advances even farther into uncharted waters, questions regarding “beginning-of-life ethics” grow more complicated.  In particular, with new methods of in vitro fertilization (IVF) on the rise, pro-lifers are now being forced to grapple with previously unthinkable moral problems: e.g., what do we do with “discarded embryos”; and is frozen embryo (a.k.a. “snowflake”) adoption morally okay?

One such problem, intracytoplasmic sperm injection (ICSI), has some “life begins at conception” advocates severely worried.  What’s particularly tricky is that it blurs the line between pre- and post-conception life. And because of that, it’s worth a quick look.

Let’s start with some facts. The biological process of fertilization is pretty simple: a male sperm cell comes into contact with a female egg cell (called an ovum), and a new cell – called a zygote – is formed.  In short, the two gametes (i.e., the sperm and the ovum) combine so that each no longer exists as it did before.  In fact, neither exists anymore at all.

This formation of a new, totally unique cell – the zygote – is the beginning of a new human life.  With all the biological material in place, and with the epigenetic programming properly enacted, the newly created zygote constitutes a new human being.

Naturally, fertilization of an ovum occurs via sexual intercourse.  But with modern science, it is also possible to fertilize an ovum using in vitro techniques – literally “in the glass.”  This entails artificially introducing male and female gametes in a laboratory, in the hopes of producing a healthy zygote.

While in vitro fertilization is itself morally illicit because it treats human life as a “product” rather than as a gift – and because it separates the procreative and unitive dimensions of human sexuality – the ethical result is fairly simple: as long as a sperm and ovum unite and form a completely new cell (zygote), a new human life is created.  End of story.

Intracytoplasmic sperm injection makes the IVF problem a little fuzzier.  In ICSI, lab workers use a micro-thin syringe to inject a single sperm cell into the female ovum.  Unlike natural conception or traditional IVF, where a sperm’s fusion with the ovum from the outside prompts a series of chemical changes that initiate the zygote phase, ICSI drops a whole sperm cell right into the ovum’s cytoplasm.  In other words, the first step of natural fertilization is bypassed.

The problem here is simple: in natural fertilization, the moment the sperm and ovum fuse membranes (one of the first steps in fertilization, occurring within microseconds), neither the sperm nor ovum any longer exists.  Instead, the former-ovum begins to harden over (preventing other sperm from penetrating) and take on a life of its own.  This change marks the beginning of the zygote – of new human life.

With ICSI, membrane fusion doesn’t occur.  How could it, since the sperm is dropped inside the ovum?  Likewise, the regular biological processes are short-circuited; and right now, we have no way of telling just when the sperm and egg cease to be, and the zygote begins.

As confusing as ICSI makes things, the basic principles of beginning-of-life ethics never change: when two cells are present – sperm and egg – there is no new human life; but when the two cells join (usually marked by membrane fusion), a new life exists.

Without initial membrane fusion, however, the problem is indeed fuzzy.  The principles still remain in effect: as long as we can still extract a living, functioning sperm cell from the ovum, a new life was never present.  We know this much.  But since ICSI is an unnatural process, the details of when gametes “fuse” are unclear.  Is it when the cytoplasm first mixes?  Or when the nucleus of the sperm is released past it’s own cell walls?

The simple answer is that we don’t know, because it doesn’t usually happen this way.

Despite this uncertainty, however, the ICSI case is a good reminder to us as Catholics that although science progresses at seemingly warp speed, solid principles are always solid principles.  In other words, even if we can’t tell immediately, by observation, when new life begins as a result of ICSI, we know at least that “new life” always means the fusion of two cells into a single, self-directed zygote.  And this is a strong leg to stand on.

As long as we hold onto our solid principles, illicit scientific progress will never get the better of us.  If we aim to understand science, and work logically through it’s processes, we can make morally defensible claims about ICSI, embryo adoption, and embryonic stem cell research that stand up against popular criticism.

And with moral principles on our side, we as defenders of human life and dignity can be confident that our position is a strong one – even in the face of continuing human error.