Makena Side Effects, Safety & Effectiveness

Pregnant women who have a history of at least one spontaneous premature birth can reduce the risk of another preterm delivery before 37 weeks of pregnancy with the help of Makena (hydroxyprogesterone caproate) which was recently approved by the U.S. Food and Drug Administration (FDA).

Says Sandra Kweder, deputy director of the Office of New Drugs in the FDA’s Center for Drug Evaluation and Research, of the newly approved drug: “Preterm birth is a significant public health issue in the United States. This is the first drug approved by the FDA that is indicated to specifically reduce this risk.”

According to the FDA news release, treatment with Makena should begin at 16 weeks and no later than 21 weeks of pregnancy. It should be administered once a week by a health care provider via injection into the hip. The drug should not be used in women with a multiple pregnancy, such as a twin pregnancy, or other risk factors for preterm birth.

The agency approved the drug after a data review on the safety and effectiveness of Makena in a multicenter randomized double-blind clinical trial. The study included 463 women 16 to 43 years of age who were pregnant with a single fetus and had a history of a prior spontaneous preterm birth. The study found that preterm delivery among women who were treated with Makena is significantly lower (37 percent) than the control group who didn’t receive a similar treatment (55 percent).

Does the drug have any effect on the kids born to mothers who had a Makena treatment? According to the FDA, a separate study which focused on the development of children born to mothers enrolled in the controlled trial found that children ages 2.5 years to 5 years reached similar developmental targets regardless of the mother’s treatment.

As to the side effects of the drug, the most commonly reported are: pain, swelling, or itching at the injection site; hives, nausea and diarrhea. Serious adverse reactions were rare according to the FDA, this include one report of a blood clot in the lungs (pulmonary embolism) and another report on an infection at the injection site.

If you experience adverse reactions to the medication, you are encouraged to report them to FDA’s MedWatch program at 800-FDA-1088 or online at


For more entries related to this topic, check out our posts on the pregnancy risks for women aged 45 and above, the side effects of Ella day-after pills, as well as the side effects of Natazia birth control pills.