Does a Disintegrated Fetus Defile a House?

The Tannaim debate whether a miscarried placenta without a discernible fetus imparts corpse impurity to a house, or if the dissolved embryo is nullified.

The Case of the Empty Placenta

A woman miscarries an afterbirth (שליא) inside a house, but no formed fetus can be seen within it. Under biblical law, a dead human body imparts severe ritual defilement (טומאת מת, corpse impurity) to the roofed room sheltering it.

The Mishnah records an essential dispute regarding the status of the building. Does a hidden fetus that has decomposed inside the placenta impart impurity, or has it lost its legal status?

The Chachamim: Impurity Persists

The majority of Sages (חכמים, the Chachamim) rule that the house becomes ritually impure. They establish a firm biological presumption: no placenta ever emerges without an offspring.

Although no physical body can be detected, we presume that an embryo was present and broke down. Because an offspring was certainly conceived, the fetus remains unnullified and continues to defile the room.

הַשִּׁלְיָא בַּבַּיִת — הַבַּיִת טָמֵא. לֹא שֶׁהַשִּׁלְיָא וָלָד, אֶלָּא שֶׁאֵין שִׁלְיָא בְּלֹא וָלָד.

If the afterbirth is in the house, the house is impure; not that the afterbirth is an offspring, but that there is no afterbirth without an offspring. (Bekhorot 22a:4)

Rabbi Shimon: Liquidated and Nullified

Rabbi Shimon rules that the house remains ritually pure. He concedes that a fetus originally existed in the mother's womb.

However, Rabbi Shimon argues that the offspring disintegrated before it was expelled. Once its tissue broke down into fluid, the fetus became nullified in the placenta fluids under the rule of majority nullification (ביטול ברוב). Because it dissolved into liquid before emergence, it lacks the substance to impart defilement.

רַבִּי שִׁמְעוֹן אוֹמֵר: וָלָד נִימּוֹק עַד שֶׁלֹּא יָצָא.

Rabbi Shimon says: The offspring disintegrated before it emerged. (Bekhorot 22a:4)

Rabbi Yochanan's Parallel in Bekhorot

The Gemara cites this dispute to explain a ruling regarding an animal that miscarries a congealed mass of blood (חררת דם). That mass does not defile by contact, yet must be buried to publicize that the mother is exempt from the law of the firstborn (בכורה).

Rabbi Yochanan explains that the miscarried animal mass is indeed an offspring, but its carcass impurity is nullified in the surrounding fluids. Rabbi Yochanan points out that Rabbi Eliezer ben Yaakov and Rabbi Shimon apply the identical logic of nullification in a majority to discharge at birth.

אָמַר רַבִּי יוֹחָנָן: מִשּׁוּם בִּיטּוּל בְּרוֹב נָגְעוּ בָּהּ.

Rabbi Yoḥanan says: It is due to the nullification in a majority that they touched upon it. (Bekhorot 22a:2)

The Halachic Decision

The halacha is decided in accordance with the Chachamim. The Rambam rules that when a woman miscarries a placenta, the house is definitely impure.

The legal presumption remains absolute that no placenta appears without a child. Although an animal's expelled blood mass is nullified according to the Rambam, a dissolved human fetus defiles the surrounding house despite its disintegration.

While Rabbi Shimon holds that a dissolved fetus is nullified in the placenta's fluids, the halacha follows the Chachamim that an expelled placenta definitely imparts corpse impurity.

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