Levonorgestrel (LNG) is a synthetic progestational hormone with actions similar to those of progesterone and about twice as potent as its racemic or (+-)-isomer (norgestrel). It is used for contraception, control of menstrual disorders, and treatment of endometriosis. It is usually supplied in a racemic mixture (Norgestrel, 6533-00-2). Only the levonorgestrel isomer is active. Within an Intrauterine device (IUD), sold as Mirena among others, it is effective for long term prevention of pregnancy. The local mechanism by which continuously released LNG enhances contraceptive effectiveness of Mirena has not been conclusively demonstrated. Studies of Mirena and similar LNG IUS prototypes have suggested several mechanisms that prevent pregnancy: thickening of cervical mucus preventing passage of sperm into the uterus, inhibition of sperm capacitation or survival, and alteration of the endometrium. Mirena has mainly local progestogenic effects in the uterine cavity. The high local levels of levonorgestrel lead to morphological changes including stromal pseudodecidualization, glandular atrophy, a leukocytic infiltration and a decrease in glandular and stromal mitoses. Ovulation is inhibited in some women using Mirena. In a 1-year study, approximately 45% of menstrual cycles were ovulatory, and in another study after 4 years, 75% of cycles were ovulatory. There has been much debate regarding levonorgestrel emergency contraception's (LNG-EC's) method of action since 1999 when the Food and Drug Administration first approved its use. Proponents of LNG-EC have argued that they have moral certitude that LNG-EC works via a non-abortifacient mechanism of action, and claim that all the major scientific and medical data consistently support this hypothesis. However, newer medical data serve to undermine the consistency of the non-abortifacient hypothesis and instead support the hypothesis that preovulatory administration of LNG-EC has significant potential to work via abortion. The implications of the newer data have important ramifications for medical personnel, patients, and both Catholic and non-Catholic emergency room protocols. In the future, technology such as the use of early pregnancy factor may have the potential to quantify how frequently preovulatory LNG-EC works via abortion. The latest scientific and medical evidence now demonstrates that levonorgestrel emergency contraception theoretically works via abortion quite often. The implications of the newer data have important ramifications for medical personnel, patients, and both Catholic and non-Catholic emergency room rape protocols.

Etynodiol (used in a form of diacetate) is a steroid that was used as a contraceptive drug. Etynodiol diacetate and etynodiol are rapidly metabolized to an active metabolite, norethisterone, which binds to progesterone receptor and modulates its activity.

Norethisterone (INN, BAN), also known as Norethindrone (USAN) (brand names Micronor, AYGESTIN, numerous others) is a synthetic progestational hormone (progestin) with actions similar to those of progesterone but functioning as a more potent inhibitor of ovulation. It has weak estrogenic and androgenic properties. The hormone has been used for the treatment of secondary amenorrhea, endometriosis, and abnormal uterine bleeding due to hormonal imbalance in the absence of organic pathology, such as submucous fibroids or uterine cancer. AYGESTIN® is not intended, recommended or approved to be used with oncomitant estrogen therapy in postmenopausal women for endometrial protection. Progestins diffuse freely into target cells and bind to the progesterone receptor. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. Once bound to the receptor, progestins slow the frequency of release of gonadotropin releasing hormone (GnRH) from the hypothalamus and blunt the pre-ovulatory LH surge. Allergic reaction could be: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing.

Norethisterone (INN, BAN), also known as Norethindrone (USAN) (brand names Micronor, AYGESTIN, numerous others) is a synthetic progestational hormone (progestin) with actions similar to those of progesterone but functioning as a more potent inhibitor of ovulation. It has weak estrogenic and androgenic properties. The hormone has been used for the treatment of secondary amenorrhea, endometriosis, and abnormal uterine bleeding due to hormonal imbalance in the absence of organic pathology, such as submucous fibroids or uterine cancer. AYGESTIN® is not intended, recommended or approved to be used with oncomitant estrogen therapy in postmenopausal women for endometrial protection. Progestins diffuse freely into target cells and bind to the progesterone receptor. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. Once bound to the receptor, progestins slow the frequency of release of gonadotropin releasing hormone (GnRH) from the hypothalamus and blunt the pre-ovulatory LH surge. Allergic reaction could be: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing.

Clogestone Acetate (AY-11440) is a steroidal progestin that was synthesized in 1964 and was investigated as a progestin-only contraceptive but was never marketed.

Nisterime is a dihydrotestosterone derivative. Nisterime acetate (ORF-9326) was shown to inhibit implantation in several species. It is also interrupts the postimplantation stage of gestation.

Dimethisterone (brand name Secrosteron) is an orally active progestational agent. It was developed by the British pharmaceutical company British Drug Houses and was first reported in the literature in 1959 with introduction for medical use as Secrosteron. Relative to ethisterone, it is 12 times as potent orally as a progestogen in animals (Clauberg test). It has an oral LD50 in mice of 7.65 g/kg, no apparent anabolic, androgenic properties and no significant effect on sodium, potassium or water excretion in saline loaded rats. Dimethisterone was introduced in the United States as an oral contraceptive for birth control in combination with ethinylestradiol under the brand name Oracon (25 mg dimethisterone, 100 ug ethinylestradiol) and was produced by Mead Johnson & Company (Evansville, Indiana) in 1974. This preparation was eventually found to be associated with a substantially increased risk of endometrial cancer in women, and is now no longer marketed.

Chlormadinone acetate (CMA) is a derivative of naturally secreted progesterone that shows high affinity and activity at the progesterone receptor. It has an anti-estrogenic effect and, in contrast to natural progesterone, shows moderate anti-androgenic properties. CMA acts by blocking androgen receptors in target organs and by reducing the activity of skin 5alpha-reductase. It suppresses gonadotropin secretion and thereby reduces ovarian and adrenal androgen production. CMA shows high contraceptive efficacy by inhibiting ovulation due to its ability to suppress or disrupt endogenous gonadotropin secretion and, by this, inhibits follicular growth and maturation. In addition, it suppresses endometrial thickness and increases the viscosity of cervical mucus. Chlormadinone acetate was withdrawn from the market in the USA, but it is still being used in Europe under the name Belara.

Phenylmercuric ammonium acetate is a fungicide and bactericide. It is used for the seed treatment.

For people with MTHFR gene variations, supplementing with the already activated form of folate (5-MTHF/5- METHYLTETRAHYDROFOLATE/LEVOMEFOLIC ACID) is far more effective in providing this form of folate than introducing the pre-converted form to the body through typical folate supplements. L-Methylfolate (5-MTHF) supplements provide the active form of folate naturally present in the body and available for biological action. 5-MTHF—the “active” form of folate that is able to pass the blood brain barrier. However, without a properly functioning methylenetetrahydrofolate reductase, MTHFR this conversion cannot take place and folate is not converted to forms that can cross the blood brain barrier. That is where 5-MTHF supplements come in. Levomefolate calcium is structurally identical to L-5-methyltetrahydrofolate (L-5-methyl-THF), a metabolite of vitamin B9. Mean baseline concentrations of about 15 nmol/L are reached in populations without folate food fortification under normal nutritional conditions. Orally administered levomefolate calcium is absorbed and is incorporated into the body folate pool. Peak plasma concentrations of about 50 nmol/L above baseline are reached within 0.5 – 1.5 hours after single oral administration of 0.451 mg levomefolate calcium. Steady state conditions for total folate in plasma after intake of 0.451 mg levomefolate calcium. In red blood cells, achievement of steady state is delayed due to the long lifespan of red blood cells of about 120 days. Levomefolate calcium is a part of contraceptive tablets: SAFYRA. Safyral is an estrogen/progestin COC (Combined Oral Contraceptive) containing a folate, indicated for use by women to: prevent pregnancy and raise folate levels in women who choose to use an oral contraceptive for contraception. COCs lower the risk of becoming pregnant primarily by suppressing ovulation. Other possible mechanisms may include cervical mucus changes that inhibit sperm penetration and endometrial changes that reduce the likelihood of implantation.