For the past few weeks, we’ve been trying to answer this FAQ: How long will it take to get pregnant after stopping birth control? We looked at how the Pill and IUDs affect the time it takes to conceive. Today, we’ll look at fertility and other popular birth control methods such as Depo, Implanon, Ortho Evra Patch and Nuva Ring.
The bulk of information about conception after Depo-Provera is based upon the older 150 mg deep muscle injection version. While the metabolites of Depo-Provera 150 may leave the body between 55-440 days, the mean time for the synthetic progesterone to be no longer detectable is about 160 days. When testing for actual return of ovulation, the range can be 77-425 days with a mean time of 211 days, or seven months (Fotherby, 1986). You may recall that I point out there is a recorded case of an 18-month delay in return to fertility. This is relatively uncommon, but the mean time to conception after stopping Depo-Provera 150mg injections is about 10 months (Pardthaisong, 1980).
What about the newer version Depo-Provera 104mg subcutaneous injection? In a very small study, the majority of women ovulated within a year, but the average time was 10 months (package insert). Mischell and colleagues (2004) conducted a head-to-head comparison of the two doses of Depo-Provera. In this controlled trial, women were given one shot only, then watched to see when ovulation returned. In the Depo-Provera 150 group, the average time to ovulation was 183 days, while the Depo-Provera 104 group had an average 212 days. These are both small studies but this early data seems to suggest that, on average, both doses of DepoProvera delay return of ovulation until 6 to 7 months after the last dose.
Implanon also contains a synthetic progesterone (etongestrel), but of a different type than Depo-Provera (medroxyprogesterone acetate). While it may take five months for the metabolites of Depo to clear the body, etongrestrel is not found after 7 days following Implanon removal (Huber, 1998). Return to ovulation and fertility can occur at about 3 months (Kiriwat, 1998 & Funk, 2005).
ORTHO EVRA PATCH
Like the combination oral contraceptives mentioned above, the Patch contains both synthetic estrogen and progesterone. This method of hormonal birth control is too new to have any long term studies on time to pregnancy. Studies have shown that it takes about six weeks for ovarian hormones to return to normal levels (Pierson, 2003).
The Ring contains both synthetic estrogen and progesterone. This birth control method has one small study where 15 women were followed after two cycles of Ring use. Return of ovulation after discontinuing the ring ranged from 13 days to slightly over a month – the average time being 19 days (Mulders, 2002). With several decades of utilization, we may have a more detailed picture of pregnancy rates after the NuvaRing.