Miscarriage

Be not grieved and afflicted for this calamity which hath befallen thee; nay, rather, rejoice that God hath favored (thy babe) with His heavenly gifts. Truly, I say unto thee, wert thou informed of that felicity which thy babe hath attained in the worlds of God, thy breast would be dilated and thy soul would be purified. Truly, I say unto thee, thy child will be fostered from the breast of the gift of God in the Exalted Kingdom and will be nursed in the bosom of mercy in the Supreme World of God. Therefore, be filled with delight, for the favor of thy Lord is very great! I beg of God to pour on thee becoming patience, so that thy heart may be consoled with the fragrance of His mercy and that thy breast may be dilated with His favors, that thou mayest attain to the spiritual states which are lasting forever and ever. Thou oughtest to bear it with becoming patience. Again, thou oughtest to patiently bear this calamity which hath flowed thine eyes with tears and hath greatly afflicted thee.

‘Abdu’l-Bahá, Tablets of ‘Abdu’l-Bahá v1, p. 139-140

From a Bahá’í point of view, the soul is present from conception and therefore the foetus, no matter how young, should not be treated with disrespect and carelessly discarded into an incinerator, if this can be prevented. The House of Justice knows of nothing in the writings specifically referring to the burial of embryos, and, in previous instances, has left such details to the discretion of the parents. In one case it was reported to the world center that the parents had buried the foetus in a corner of their own garden and had said a few prayers for the progress of their child's soul.

Universal House of Justice, Lights of Guidance, p. 195