[1].     Igros Kodesh of the Rebbe Rayatz, Vol. 9, p. 290. Likkutei Sichos, Vol. 12, p. 178. Igros Kodesh of the Rebbe, Vol. 3, p. 387; Vol. 4, p. 112; Vol. 5, p. 221; Vol. 7, p. 303; Vol. 8, p. 193; Vol. 11, p. 278.

[2].     Likkutei Sichos, ibid.; Igros Kodesh of the Rebbe, Vol. 8, p. 209 (with the addition that one may all tell one’s children about it); Vol. 11, p. 278.

[3].     Cf. Igros Kodesh of the Rebbe Rayatz, Vol. 9, p. 284: “The accepted practice is that until three months of pregnancy it is concealed even from very close relatives...”

[4].     Igros Kodesh of the Rebbe Rayatz, Vol. 9, p. 451.

[5].     Alter Rebbe’s Siddur. Likkutei Sichos, Vol. 22, p. 59, note 36:

We need not be concerned about the possibility of twins (as Bach writes ibid. quoting Mordechai Katan 43) — since that is a rare occurrence, and we are only dealing with a custom.

These days the situation requires further clarification, for many times it is known with certainty that she is carrying twins. Since we rely on this knowledge regarding questions of life and death etc., should she also act accordingly with regard to kapporos, or should we say that [she may still ignore it] because it is rare; and especially here, where in any case some authorities say that several males can discharge their obligation with a single rooster.

[6].     In Likkutei Sichos, ibid., par. 6, the question is asked — why would an unborn fetus require any atonement...? He explains that if the woman ate forbidden food while pregnant, this has been transformed into her own blood and flesh and for this, she requires atonement — the food becomes blood in the woman’s heart, and also in the heart of the fetus... (see source at length, and references cited there).

[7].     Ibid., note 34:

This is the opinion of the AriZal cited in Magen Avraham, loc. cit., quoting Shaloh (beg. of p. 236b), second opinion in the Alter Rebbe’s Shulchan Aruch (605:3), and Bach, loc. cit.: “I have discovered a text quoted from Mordechai Katan stating that a pregnant woman requires three kapporos, and this also appears to be the opinion of Darkei Moshe, loc. cit. (par. 2): ‘furthermore, it is customary to take for a pregnant woman two hens and one rooster, since we are in doubt whether she will give birth to a son or a daughter’; we find the same thing in Eliyahu Zuta, loc. cit. (par 4), and Eliyahu Rabbah, loc. cit. (par. 8).”

Ibid., note 35:

This is the text of the Alter Rebbe in his Siddur, “Procedure for Kapporos,” where he does not cite the first opinion. Examine the exact wording of the text in the above sources, and in Shaar HaKavannos in Siddur HaAriZal, Pri Etz Chayim, and Shaloh, ibid.

[8].     Likkutei Sichos, Vol. 22, p. 58ff. The explanation appears in par. 4:

It is written in Shulchan Aruch in regard to the “Custom of Kapporos on Erev Yom Kippur” (that is the chapter title in Shulchan Aruch, and that of the Alter Rebbe in 605:3) that (in addition to the hen for her own kapporoh) a pregnant woman takes a rooster for the kapporoh of the fetus...

Accordingly, we may infer with regard to our case of a pregnant woman [serving as kvatterin]: the Jewish custom is that there should be exactly two, a man and a woman (or else two of each), and thus it turns out that we would have three people accompanying them or serving as kvatters; also, the number of males and females would not be equal, and perhaps this is also important.

One might ask: the one who accompanies, or the kvatterin, is actually the mother (not the fetus); so why is it different from other people who are standing there, about whom we are not concerned? The difference is obvious: other people are not present in the role of accompanying or of kvatterins, but the fetus is a part of its mother, and thus must also be counted as part of the accompaniment or the kvatters.

Likkutei Sichos, ibid., note 27:

See Ibn Ezra on Shemos 4:5: “It is the custom of women to call a male child chosson when he is circumcised.” The child is also dressed in fine clothing, as on the day of his marriage.

The Sichah concludes that both instances constitute a single custom. In note 28, Michtav Oz of the Minchas Elazar is cited.

[9].     Igros Kodesh of the Rebbe, Vol. 18, p. 51, with the addition: “On the other hand, since your wife’s family does have such a custom, obviously you should not prevent her from doing this. Of course, it should be done only with the physician’s permission.” See also Otzar HaBris 1:7:12.

[10].   Igros Kodesh of the Rebbe, Vol. 3, p. 387; Vol. 5, pp. 105, 220, and 327, with the addition: “She should add eighteen pennies each time, to what she has been giving until now to the charities of R. Meir Baal HaNess before candle-lighting.” See also Vol. 7, pp. 108, 303, and elsewhere. Otzar HaBris 3:7:6 cites Iggeres HaTeshuvah of Rabbeinu Yonah, sec. 82 and others.

[11].   Igros Kodesh of the Rebbe, Vol. 5, pp.105, 220; Vol. 7, p. 303. This is in reply to someone who inquired about special procedures during the months of pregnancy. This reply was given as one of these procedures.

[12].   Igros Kodesh of the Rebbe, Vol. 4, pp. 454, 492; Vol. 5., pp. 105, 220. Cf. Likkutei Mahariach, Vol. 3, quoting Midrash Talpiyos (section on women giving birth), that this psalm should be recited silently (there, it refers to the time of the actual delivery).

[13].   Sichah of 19 Kislev 5747 (edited) — regarding care to be taken with a woman giving birth, including at the hospital (printed in Hisvaadiyos 5747, Vol. 2, p. 37; Teshuvos U’Biurim BeShulchan Aruch, p. 446).

[14].   See sources cited in Otzar HaBris 3:7.

[15].   Hisvaadiyos 5750, Vol. 3, p. 179.

[16].   See Rama, Yoreh De’ah, end of Ch. 198; see also Shach, ibid.; Likkutei Sichos, Vol. 25, p. 310.