Review of the Marquette Breastfeeding Study
Reviewed by Rebecca Peck, MD
There are few NFP studies which examine the applicability of an NFP method during the breastfeeding and weaning stages of the postpartum period. NFP instructors have long known that this period can be especially challenging due to the woman’s unclear cervical mucus and temperature signs (Kennedy, Gross, Parenteau-Carreaus, Flynn, Brown, and Visness, 1995; Labbok, Stallings, Shah, Perez, Klaus, and Jacobson, et al., 1991). Some methods of NFP (during breastfeeding) overestimate the actual days of fertility and lead to long stretches of confusing mucus patterns and required abstinence. Moreover, the Basal Body Temperature (or BBT) shift will not be a helpful sign until after ovulation occurs, thereby limiting its usefulness during this period (Zinaman and Stevenson, 1991). The Lactational Amenorrhea Method (exclusive breast feeding during the first 6 months postpartum) is a highly effective way to avoid pregnancy but women still need help in identifying their fertile period during the weaning period (Tommaselli, Guida, Palomba, Barbato and Nappi, 2004). Typical efficacy rates of NFP studies during this period, therefore, are usually lower due to these challenges (Zinaman and Stevenson, 1991; Labbok, et al., 1991). Recently, for example, a Breastfeeding Bridge Method developed for Users of the Standard-Days Method of NFP, reported 16 unintended pregnancies per 100 women over 6 months of use (Sinai and Cachan, 2012).
A successful Marquette breastfeeding protocol was developed by Bouchard, Fehring, and Schneider (Bouchard, et al., 2013) for breastfeeding women that utilizes a hand-held urinary hormonal monitor in conjunction with an internet-based charting system. The breastfeeding protocol creates artificial cycles of 20 days during the postpartum amenorrheic period, whereby women test urinary estrone 3 gluconorate (E3G) and Luteinizing Hormone (LH) from days 6-26 on the monitor, i.e., the 20 days that the monitor will ask for a test strip and read it. If, during a 20 day interval, no LH surge has been detected, the monitor is retriggered to start a new 20 day interval. This method accurately signifies the onset of approaching fertility, which is known by increasing number of “highs” (which indicates the rise of urinary E3G from baseline), proceeding to an eventual “peak” (known by an increase of urinary LH), followed by ovulation and eventual resumption of the menses. Once the menses resumes, the monitor is used the traditional way, with urinary hormonal testing beginning on Day 6. Online instruction, charting and a users forum was available for study participants (see, http://nfp/marquette.edu).
The Efficacy of a New Postpartum Transition Protocol for Avoiding Pregnancy was a prospective, 12-month, longitudinal cohort study in which 198 postpartum women aged 20 to 45 years were taught the above protocol for avoiding pregnancy with either online or in-person instruction. Participants were instructed to avoid intercourse during the identified fertile period. Kaplan-Meier survival analysis was used to calculate unintentional pregnancy rates through the first 12 months postpartum. There were 8 unintended pregnancies per 100 women at 12 months postpartum. With correct use, there were 2 unintended pregnancies per 100 women at 12 months. The authors concluded that the online postpartum protocol may effectively assist a select group of women in avoiding pregnancy during the transition to regular menstrual cycles.
The authors acknowledge that their participants were largely white, married and Catholic which limits the generalizability of their study to the general population. Moreover, the cost of the monitor and testing strips may be perceived as too high by some. Finally, the lack of a control group is a real concern of this study as well as of the other existing NFP research pertaining to the postpartum period. However, the typical use efficacy rates found in this study are encouraging and among the lowest found in the existing postpartum NFP research. Randomized controlled trials will be needed to effectively compare the different methods
1. Bouchard, T., Fehring, R., Schneider, M. 2013. Efficacy of a new postpartum transition protocol for avoiding pregnancy. Journal of the American Board of Family Medicine 26: 35-44; see, http://www.jabfm.org/cgi/content/abstract/26/1/35.
2. Kennedy, K. I., B. A. Gross, S. Parenteau-Carreaus, A. M. Flynn, J. B. Brown, and C. M. Visness. 1995. Breastfeeding and the symptothermal method. Studies in Family Planning 26: 107-115.
3. Labbok, M. H., R. Y. Stallings, F. Shah, A. Perez, H. Klaus, M. Jacobson, et al. 1991. Ovulation method use during breastfeeding: is there increased risk of unplanned pregnancy? American Journal of Obstetrics and Gynecology 165 (Suppl): 2031-2036.
4. Tommaselli, G. A., M. Guida, S. Palomba, M. Barbato, and C. Nappi. 2000. Using complete breastfeeding and lactational amenorrhea as birth spacing methods. Contraception 61: 253–255.
5. Sinai, I., and J. Cachan. 2012. A bridge for postpartum women to Standard Days Method, I and II. Contraception 85 (3): 331-332.
6. Zinaman, M., and W. Stevenson. 1991. Efficacy of the symptothermal method of natural family planning in lactating women after the return of menses. American Journal of Obstetrics and Gynecology 165 (Suppl): 2037-2039.