Preventing Unintended Pregnancies by Providing No-Cost Contraception, a study carried out by Dr. Jeffery Peipert and the team at the Contraceptive CHOICE Project, provided women with free contraceptives, including the more initially expensive long-acting reversible contraceptives (LARCs) such as IUDs and implants. During a three-year period, their study group of almost 10,000 women in the CHOICE project had abortion rates statistically significantly lower than women in the greater metropolitan area.

So do free contraceptives, especially LARCs, lower abortion rates? Let me show you how I examined the study and why I think not.

What kind of study is this?

There are different kinds of medical research. An ecological study looks at two or more variables across a population (e.g. the BMJ study associating OCP use with prostate cancer). Ecological studies provide the weakest evidence for causation, since innumerable factors could confound the link. A cohort study provides a slightly stronger level of evidence. Cohort studies select a population of patients who are exposed to a particular variable of interest and studies them over time (e.g. Sexual Behavior and OC: A Pilot Study).

What kind of research is Dr. Peipert’s study? At first I labeled it a cohort study: it’s watching an exposed group over time for a variable (numbers of unintended pregnancies). But the study itself reads:

the analysis comparing repeat abortion in the St. Louis region with that in Kansas City and nonmetropolitan Missouri is essentially an ecological study. There may be several factors that affect the rates of repeat abortion, such as the economic recession, federal changes in Title X funding for family planning, and Missouri state laws that limit access to abortion.

So, it’s more than likely that the study is is a hybrid of the lowest standard of evidence for causation and a slightly higher one.

Are there confounding variables?

Patient self-selection is may be a factor. The CHOICE project was advertised by ”newspaper reports, study flyers, and word of mouth,” and participants were either self-referred, or ”recruited from the two abortion facilities in the St. Louis region and through provider referral….”

It’s not inconceivable that patients who had a pre-existing desire for LARC joined the study to have these relatively expensive methods provided at no cost. The CHOICE project counseling that patients at WUSTL received heavily emphasized LARCs, even before patients were enrolled in the study. There are no controls for women’s baseline interest in LARCs or their relative motivation to avoid pregnancy in the study.

What did they do? 

To learn more about the CHOICE project, I read the study describing how the CHOICE project enrolled and counseled patients. Enrollment as described here did not include a medical records review other than a history; there was no physical exam by the contraceptive prescriber; participants were interviewed by a trained counselor who often did not have a healthcare background; and there were no follow-up face-to-face interviews or exams (participants were followed up by telephone at three and six months after enrollment, and every six months thereafter).

I am also mystified by the hazy quantification of the key outcome (unintended pregnancies). I imagined that participants would be asked “were you pregnant in the last six months” and (if yes) “did you mean to get pregnant?”

But instead, Peipart et al. report proxies of unintended pregnancies like repeat abortions, abortions, and teen births. Repeat abortions were counted by the abortion facilities working with the CHOICE project; teen births were counted by state vital statistics records. The study does not detail how abortions were counted, so I contacted the corresponding author. Were abortions or unintended pregnancies measured directly in any way, such as by questionnaire or medical record review? His reply:

Outcomes were measured by telephone interview and asking each participant if they experienced a pregnancy or if they missed a menstrual period. [Awesome! I thought that would do it!] If they did miss a period (or were late), we would encourage them to come in for a pregnancy test.  Some (but not all) pregnancies were validated with a medical chart review, when available. [Oh. That sounds...not very rigorous.]

First: how can the direct assessment of the key outcome variable be so unimportant as to not be included in the paper? An entire paper was published detailing how many women chose IUDs and implants, but I had to contact the author about the key variable in CHOICE’s pinnacle study??

Second: why didn’t the team include all their data in the study? A table quantifying missed periods, true and false positive pregnancy tests, and possible pregnancies lost to follow up would have been completely appropriate. In fact, I expected it and became wary when I didn’t find it.

What are the results?

As I stated above, the abortion rates for the CHOICE project participants were lower than for the surrounding area. These results were measured over three years, which I consider slightly premature given that 75% of the participants chose LARCs, which last 3 to 10 years (3 for an implant; 5 to 10 for an IUD). What happens to these women long-term? There is evidence to show that contraceptives reduce abortion rates and unplanned pregnancies in the short-term and increase them in the long run.

We at 1Flesh care about our patient’s long-term, cost-effective reproductive health. We’re into excellent medicine, continuity of care, and healthy and beautiful sex for her, her spouse, her daughters, and her whole community.

How should a doctor change her practice based on this?

Even if this study had impeccable design, eliminated all confounding variables, was carried out over ten years, and was reproducible, it wouldn’t matter to a doctor who practiced evidence-based medicine. A physician who bases her practice on solid research doesn’t allow vogues to replace a true gold standard. The true gold standard for avoiding unintended pregnancy is (and always will be) avoidance behavior, which Creighton and other NFP methods have described and quantified short and long-term.

In short…

Free contraceptives, even LARCs, may lower abortion rates short-term, but I can’t find this study completely conclusive. Although I could hope for cleaner study design, more of the collected data, and long-term results, why wait when effective and superior family planning techniques exist?