If a woman had a miscarriage, and estimates that the fetus was between 2-3 months, and furthermore the pregnancy was Ectopic.
Does the child born after require pidyon haben ? Does he require it without a b’racha ?
A pidyon ha-ben should be performed.
See below for more details.
The Mishnah (Bechoros 8a) writes that a firstborn that is born after a miscarriage is considered to be a firstborn with regard to inheritance, but not with regard to pidyon ha-ben. The Mishnah explains that this refers to a miscarriage after forty days of pregnancy; if the fetus is less than forty days old, the child born after the miscarriage has the full status of a firstborn.
This principle is ruled by the Shulchan Aruch (Yoreh De’ah 305:23).
If there is a doubt as to the precise age of the fetus at the time of the miscarriage, the firstborn child is exempt from pidyon ha-ben, out of doubt (Shulchan Aruch 305:13).
However, the Rema (23) adds that if the limbs of the fetus are yet unformed, the firstborn child that follows him is obligated in pidyon ha-ben (based on Maharik 143).
The simple understanding of thie ruling does not refer to a case where the miscarried fetus was not checked, but to a case where it was checked, and no limbs could be discerned (see Chacham Tzvi 104, who explains that where the fetus was not checked, we assume that it’s limbs were regularly formed).
However, the Pischei Teshuvah (39) cites several authorities who understand, based on the Maharik, that where the fetus was not checked, we assume that the following firstborn is obligated in pidyon ha-ben (the fetus is assumed to not have developed limbs; this is because of an assumption (chazakah) that the womb has not yet “become exempt” from pidyon ha-ben).
See especially Noda Biyhuda, Tinyana, Yoreh De’ah 188, who writes that until the end of the first trimester (first three months), the fetus cannot be assumed to have formed limbs, and the following firstborn is obligated in pidyon ha-ben. See also Shivas Tzion (46).
Therefore, one can conclude as follows:
1) If forty days have not passed since conception, the fetus does not exempt the subsequent firstborn from pidyon ha-ben.
2) If forty days have passed, but the first trimester (meaning the first three months of the pregnancy) was not reached, the pidyon ha-ben must be performed out of doubt, but no berachah should be recited.
3) If the miscarriage was after three months of pregnancy, no pidyon ha-ben is performed for the subsequent firstborn.
The fact that the birth was ectopic strengthens the obligation of the next child, because the first child is not a peter rechem. See: Shevet Ha-Levi (8:239); Nishmas Avraham (Yoreh De’ah 305:5); Mishnah Halachos 7:199.