Guam - Women on birth control pills should be warned: pharmaceutical giant Pfizer has ordered the recall of at least a million oral contraceptive packets of Lo/Ovral-28 and its generic brand. Pfizer indicates that the pills may not be potent enough to prevent pregnancy due to mispackaging.

Guam obstetrician and gynecologist Dr. Thomas Shieh told KUAM News, "For patients who are on these pills, lo oval, which is a low-dose birth control pill they should get off it and they use a non-hormonal birth control method at least for now until they get their menstrual cycle. So for those who are on it, they should check their package. I think it's between March 2013 to July 2014 - that's the expiration date. So talk to the pharmacist to make sure that it's not part of the recall list if they are they should probably use condoms for now."

Dr. Shieh advises that despite the recall, women should understand that birth control effectiveness is not guaranteed and ranges from 97.5% to 99% effective. Dr. Shieh adds that the island delivers 3,000 babies a year.