Postpartum contraception: a missed opportunity to prevent unintended pregnancy and short inter-pregnancy intervals

This review provides an update of previous estimates of first-year probabilities of contraceptive failure for all methods of contraception available in the United States. Estimates are provided of probabilities of failure during typical use (which includes both incorrect and inconsistent use) and during perfect use (correct and consistent use). The difference between these two probabilities reveals the consequences of imperfect use; it depends both on how unforgiving of imperfect use a method is and on how hard it is to use that method perfectly. These revisions reflect new research on contraceptive failure both during perfect use and during typical use. Copyright © 2011 Elsevier Inc. All rights reserved.

Insertion of an intrauterine device (IUD) at different times or by different routes during the postpartum period may increase the risk of complications. We searched Medline, Lilacs and Cochrane Collaboration databases for articles in any language, between database inception until December 2008, which compared outcomes of postpartum IUD insertion time intervals. Search terms included postpartum, puerperium, postcesarean delivery, cesarean section, IUD(s), IUCD(s), intrauterine device(s) and insertion. From 297 articles, we identified 15 for inclusion in this review: all studies examined the outcomes from copper IUD insertions within the postpartum time period compared to other time intervals or compared routes (vaginal or via hysterotomy) of postpartum insertion. No studies of levonorgestrel IUDs were identified. Immediate IUD insertion (within 10 min of placental delivery) was safe when compared with later postpartum time periods and interval insertion. Immediate postpartum IUD insertion demonstrated lower expulsion rates when compared with delayed postpartum insertion but with higher rates than interval insertion. Immediate insertion following cesarean delivery demonstrated lower expulsion rates than immediate insertion following vaginal delivery. Poor to fair quality evidence from 15 articles demonstrated no increase in risk of complications among women who had an IUD inserted during the postpartum period; however, some increase in expulsion rates occurred with delayed postpartum insertion when compared to immediate insertion and with immediate insertion when compared to interval insertion. Postplacental placements during cesarean delivery are associated with lower expulsion rates than postplacental vaginal insertions, without increasing rates of postoperative complications.

To estimate, from the literature, when nonlactating postpartum women regain fertility. We searched PubMed and Cochrane Library databases for all articles (in all languages) published in peer-reviewed journals from database inception through May 2010 for evidence related to the return of ovulation and menses in nonlactating postpartum women. Search terms included "Fertility" (Mesh) OR "Ovulation" (Mesh) OR "Ovulation Detection" (Mesh) OR "Ovulation Prediction" (Mesh) OR fertility OR ovulat* AND "Postpartum Period" (Mesh) OR postpartum OR puerperium AND Human AND Female. We included articles assessing nonlactating women's first ovulation postpartum. Studies in which women breastfed for any period of time or in whom lactation was suppressed with medications were excluded. We identified 1,623 articles; six articles reported four studies met our inclusion criteria. In three studies utilizing urinary pregnanediol levels to measure ovulation, mean day of first ovulation ranged from 45 to 94 days postpartum; 20%-71% of first menses were preceded by ovulation and 0%-60% of these ovulations were potentially fertile. In one study that used basal body temperature to measure ovulation, mean first ovulation occurred on day 74 postpartum; 33% of first menses were preceded by ovulation and 70% of these were potentially fertile. Most nonlactating women will not ovulate until 6 weeks postpartum. A small number of women will ovulate earlier, potentially putting them at risk for pregnancy sooner, although the fertility of these early ovulations is not well-established. The potential risk of pregnancy soon after delivery underscores the importance of initiating postpartum contraception in a timely fashion.