Contraindications
Contraindications of OHPC include previous or current thrombosis or thromboembolic disease, known or suspected breast cancer, past or present history of other hormone-sensitive cancer, undiagnosed abnormal vaginal bleeding unrelated to pregnancy, cholestatic jaundice of pregnancy, liver tumors or active liver disease, and uncontrolled hypertension. A few relative contraindications also exist for OHPC. Side effects
OHPC is generally well tolerated and produces relatively few side effects. Injection site reactions such as pain, soreness, swelling, itching, bruising, and lumps are the most common side effect of OHPC. In contrast to large doses of progesterone however, which produce moderate-to-severe such reactions, OHPC is relatively free from injection site reactions. Side effects of OHPC that occur in greater than or equal to 2% of users include injection site pain (34.8%), injection site swelling (17.1%), urticaria (12.3%), pruritus (7.7%), injection site pruritus (5.8%), nausea (5.8%), injection site nodules (4.5%), and diarrhea (2.3%). Numerically increased rates relative to controls of miscarriage (2.4% vs. 0%), stillbirth (2.0% vs. 1.3%), admission for preterm labor (16.0% vs. 13.8%), preeclampsia or gestational hypertension (8.8% vs. 4.6%), gestational diabetes (5.6% vs. 4.6%), and oligohydramnios (3.6% vs. 1.3%) have been observed with OHPC in clinical trials in which it was given to pregnant women to prevent preterm birth. Overdose
There have been no reports of overdose of OHPC. In the event of overdose, treatment should be based on symptoms. OHPC has been studied in humans at high doses of 2,000 to 5,000 mg per week by intramuscular injection, without safety concerns.
Follow-up of other babies exposed in utero to vaginal progesterone would be helpful in determining whether the increased rate of some renal, gastrointestinal, and respiratory complications is a real effect or a type I error. The journal reviewer Richard Lehman, senior Research Fellow at the Department of Primary Health Care at the University of Oxford, made the following notable commentary on the OPPTIMUM study: "Thats it. This story is ended, and nobody need ever use vaginal progesterone again to prevent preterm birth. "A Cochrane review on progestogen for preventing preterm birth concluded that there was little evidence that either vaginal or intramuscular progesterone helped to reduce the risk of preterm birth in women with a multiple pregnancy. Gynecological disorders
OHPC is used in the treatment of threatened miscarriage, gynecological disorders such as dysmenorrhea, premenstrual syndrome, fibrocystic breast disease, adenosis, and breast pain. In addition, OHPC is used in the treatment of endometrial cancer and has been found to be significantly effective in extending life in both premenopausal and postmenopausal women with the disease. The medication was used widely in the 1950s through the 1970s for such indications, but OHPC more recently has received the most attention in the prevention of preterm birth. Birth control
OHPC is available in combination with estradiol valerate as a once-monthly combined injectable contraceptive in a few countries. Other uses
OHPC has been used as a component of menopausal hormone therapy in women.OHPC has been used to treat benign prostatic hyperplasia in men, although evidence of effectiveness is marginal and uncertain.