"Question 4. Is it permissible to give a mother in extreme illness medicine to expel a fetus? Reply. Firstly, it is certain that it is not permissible for a mother outside of danger of death to take medicine for expelling even an inanimate fetus, since directly impeding the life of a human being is a grave sin, and a still graver one if the fetus is animate. It is certain, secondly, that it is not permissible for a mother even in danger of death to take medicine for expelling an ensouled fetus directly, since this would be procuring the child's death directly. The question is rather whether it is permissible for a mother to take a medicine absolutely necessary to save her life when it involves danger of expulsion of the fetus. The reply is that, if the fetus is inanimate, the mother may certainly ensure her life, even though, unintentionally on her part, expulsion of the fetus results, an expulsion for which the mother is not responsible, since she is only using her natural right to preserve her life. If the fetus is animate, it is generally held that a mother may take a medicine whose direct purpose is to save her life when nothing else will save it; but it is different in the case of medicines that of themselves are directed to killing a fetus, which it is never permissible to take" ((Latin)Alphonsus Maria de Ligorio, Theologia Moralis (Bassano 1831), vol. 1, pp. 247-248); lihat pula (Inggris)Timothy Lincoln Bouscaren, When Mother or Baby Must Die (originally published in 1933; reprint: Tradibooks 2008 ISBN 978-2-917813-01-0), p. 61.
(Inggris) Johnstone, Brian V. (March 2005). "Early Abortion: Venial or Mortal Sin?". Irish Theological Quarterly. 70 (1): 60. doi:10.1177/002114000507000104. An excerpt can be found here.
(Inggris) Johnstone, Brian V. (March 2005). "Early Abortion: Venial or Mortal Sin?". Irish Theological Quarterly. 70 (1): 60. doi:10.1177/002114000507000104. An excerpt can be found here.
"Question 4. Is it permissible to give a mother in extreme illness medicine to expel a fetus? Reply. Firstly, it is certain that it is not permissible for a mother outside of danger of death to take medicine for expelling even an inanimate fetus, since directly impeding the life of a human being is a grave sin, and a still graver one if the fetus is animate. It is certain, secondly, that it is not permissible for a mother even in danger of death to take medicine for expelling an ensouled fetus directly, since this would be procuring the child's death directly. The question is rather whether it is permissible for a mother to take a medicine absolutely necessary to save her life when it involves danger of expulsion of the fetus. The reply is that, if the fetus is inanimate, the mother may certainly ensure her life, even though, unintentionally on her part, expulsion of the fetus results, an expulsion for which the mother is not responsible, since she is only using her natural right to preserve her life. If the fetus is animate, it is generally held that a mother may take a medicine whose direct purpose is to save her life when nothing else will save it; but it is different in the case of medicines that of themselves are directed to killing a fetus, which it is never permissible to take" ((Latin)Alphonsus Maria de Ligorio, Theologia Moralis (Bassano 1831), vol. 1, pp. 247-248); lihat pula (Inggris)Timothy Lincoln Bouscaren, When Mother or Baby Must Die (originally published in 1933; reprint: Tradibooks 2008 ISBN 978-2-917813-01-0), p. 61.
(Inggris) McIntyre, Alison. "Doctrine of Double Effect". Dalam Edward N. Zalta. Stanford Encyclopedia of Philosophy (edisi ke-Summer 2006). Diakses tanggal 2007-08-18.