May one take the morning after pill if they have a Heter from a Rav to be on birth control and for whatever reason did not use a contraceptive?[1]

There are two main types of morning-after pills available for emergency contraception. The first is a pill which prevents ovulation and conception, while the second is a pill that aborts a conception. While the first type of pill is permitted to be taken by one who has a regular Heter to be on a contraceptive in the event of an emergency. The second type of pill, which aborts the fetus and conception may only be taken under very strict circumstances of potential Pikuach Nefesh and under the strict guidance of a Rav.

Examples of permitted morning-after pills: Levonorgestrel-based pills, such as Plan B One-Step, Take Action, and My Way, and Postinor in Israel are permitted.[2] Another type of permitted pill is the ulipristal acetate pills, such as Ella, which contain ulipristal acetate, a selective progesterone receptor modulator which delays ovulation to prevent fertilization.[3]

Examples of forbidden morning-after pills: Mifegyne, known in the U.S. as Mifeprex and in Israel as מיפג’ין and generically as Mifepristone, is a medication used for the medical termination of pregnancy. Commonly referred to as an abortion pill, it works by blocking the hormone progesterone, which is essential for sustaining pregnancy.

[1] See Asia Journal 15 p. 380; Rofei Uman p. 361; Asher Chanan 6:7

[2] These pills contain levonorgestrel, a synthetic hormone similar to progesterone, and work primarily by delaying or preventing ovulation. They may also alter cervical mucus or the uterine lining, but they do not impact an existing pregnancy. Levonorgestrel pills are most effective when taken within 72 hours of unprotected intimacy, though they can work up to five days afterward, with their effectiveness decreasing over time. These pills are readily available over-the-counter and do not require a prescription.

[3] These pills are more effective at delaying ovulation even if the luteinizing hormone surge has begun, making them suitable for use within 120 hours (five days) after unprotected intimacy. Unlike levonorgestrel-based pills, ulipristal acetate pills require a prescription to obtain.