While there is some Jewish disagreement on abortion, it is a duty if the mother's life is at risk

The assumption of the verse couldn’t be clearer – the term ‘harm’ doesn’t apply to the fetus. Only the pregnant woman is capable of being ‘harmed’.

The loss of the fetus is of value, but the loss of the fetus does not trigger the Biblical response ‘life for life,’ for the fetus is not a full life.

This clear assumption underlies Mishnah Ohalot 7:6.

If a woman has difficulty in childbirth, the embryo within her should be dismembered limb from limb, because her life takes precedence over its life.

Once its greater part [or head], has emerged, it may not be touched for one does not push off a soul for a soul. Rashi (on Sanhedrin 72b) explains this teaching as follows [The embryo is dismembered] limb from limb because as long as it has not emerged into the world it is not a human being – lav nefesh hu – and therefore it can be killed to save the mother.

Until birth, the fetus is understood by the Talmud (Sanhedrin 80b) as ‘a limb of the mother.’ This approach lines up neither alongside a claim that abortion is a ‘right,’ nor a claim that abortion is ‘murder.’

As the leading contemporary Masorti medical ethicist, Rabbi Elliot Dorff, wrote "Neither men nor women may amputate their thigh at will because our bodies belong to God, we have them on trust and hence we are forbidden to inflict injuries on ourselves. "

On the other hand, if the thigh turns gangrenous, then both men and women have the positive duty to have their thigh amputated in order to save their lives. Similarly, if the woman’s life or health is at stake, an abortion must be performed to save the life or the physical or mental health of the woman.

Where there are differences in Jewish approaches to abortion, they lie in an assessment of what level of threat to the mother justifies removal of the ‘limb.’ Most of these responses pay attention to the process of fetal development – Rabbinically an embryo under 40 days post-conception is considered ‘mere water’ (Yevamot 69b), and there is rabbinic unanimity that earlier abortions are more easily justified than late.

The first Sephardi Chief Rabbi of modern Israel, Rav Ben Zion Uziel (Mispetie Uziel C20 HM 3:46) articulates a maximalist position:

It is clear that abortion is not permitted without reason, but for a reason – even a weak reason – taam halush – such as to prevent her public shame, we have precedent and authority to permit it [even up to the point of labour!].

And the Ashkenaz founder of a systemic approach to Jewish medical ethics, Eliezer Waldenberg articulates a more minimal position permitting abortion up to three months ‘where there is reason to believe a child would be deformed or would experience pain,’ and at a later point only if defects are only detected at such a later point (Titz Eliezer 9:237).

Waldenberg doesn’t consider maternal mental distress in his response. The Masorti Committee on Jewish Law and Standards takes the position that:

Abortion is justifiable if a continuation of pregnancy might cause the mother severe physical or psychological harm, or when the fetus is judged by competent medical opinion as severely defective.

To which I would wish to add that, in the assessment of the psychological harm that pregnancy might cause the mother, ishah neemenet – the woman is to be believed..

I accept that women do not seek abortion frivolously and oppose the placing of obstacles before a person expressing distress when faced with a pregnancy they feel unable to carry to term with the love that all children deserve.