Ulipristal Acetate (Contraceptive)

Ulipristal acetate is a selective modulator of progesterone receptors. It inhibits or delays ovulation and alters the endometrium.
It is used as an emergency contraceptive for up to 120 hours (5 days) after intercourse and in the treatment of uterine fibroids.

This entry reports on its use as AN EMERGENCY ANTICONCEPTIVE.

Its high percentage of plasma protein binding explains the very small transfer to milk observed, which is at its maximum during the first day: 0.013 mg in total (EMA 2013: 5.2) or 0.023 mg/L (HRA Pharma 2015: 8.3), decreasing to one-seventh in the next 24 hours and still much less over the next 4 days (HRA Pharma 2015: 8.3, EMA 2013: 5.2).

As an emergency contraceptive it is a medication for limited and occasional use and the total relative dose ingested by the infant would be less than 1% in 5 days.

Intestinal absorption by the infant of the low dose excreted in breastmilk would be hindered, since oral bioavailability decreases up to 45% if administered with fat-rich foods, such as breastmilk.

The World Health Organization believes that it can be used as an emergency contraceptive during breastfeeding (Batur 2016, WHO 2015), but its recommendation to interrupt breastfeeding for a week (Sridhar 2017, WHO 2015 p72) is surprising, as it is based solely on the manufacturer's information.

Given the minimal excretion of the product in breastmilk and the absence of adverse effects recorded during breastfeeding, it is difficult to justify the recommendation proposed by other authors or health agencies such as CDC to interrupt breastfeeding for 24 hours (Curtis 2016 Table J1 p93) or 36 hours (Mansour 2009).

See below the information of this related product:

• Ulipristal Acetate (treatment of Myomas, Fibroids) (Fairly safe. Mild or unlikely adverse effects. Compatible under certain circumstances. Follow-up recommended. Read Commentary.)