The effect of levenogesterol (Norplant) contraception on coagulation as measured by antithrombin-III levels

Abstract

Purpose: To determine the effect of contraception given immediately postpartum on coagulation as measured by antithrombin III.

Study design: In this prospective study, parturients (n = 85) self selected three means of postpartum contraception: levenorgesterol implants, oral contraceptives, or a barrier method.

Results: Baseline coagulation was assessed by antithrombin-III levels in each of the 85 women within 48 hours of delivery (100.35 +/- 1.61%) and at one (109.1 +/- 1.89%) and six (105.51 +/- 1.71%) weeks postpartum. There was a rise in antithrombin-III after delivery but there were no significant differences between the groups.

Conclusion: The levenorgesterol implant system did not cause a decrease in antithrombin-III in normal parturients.

PIP: The effect of postpartum Norplant implant use on coagulation factors was investigated in a prospective study conducted in Mississippi, US. 85 postpartum women were given a choice of 3 contraceptive methods: levonorgestrel implants (n = 25), oral contraceptives (n = 38), or a barrier method (n = 22). Antithrombin-III (AT-III) levels were measured on the day of discharge from the hospital after delivery, 7 days after delivery, and 6 weeks after delivery. There was no significant difference between groups in the initial AT-III level (mean, 100.35 +or- 1.61%). At the end of the first postpartum week, AT-III levels rose significantly to 109.1 +or- 1.89%, but again, there were no significant differences according to contraceptive method. By the 6-week follow-up, AT-III levels had stabilized at a mean of 105.51 +or- 1.71%, with no significant between-group differences. AT-III levels in pill users declined more markedly between the first and sixth postpartum weeks than those in the 2 other groups. These findings indicate that subdermal implant use does not affect coagulation, and these devices can be inserted safely during the postpartum period.