Postpartum Use of Long-Acting Reversible Contraception in a Military Treatment Facility

Introduction

An estimated 54% of all pregnancies in the U.S. military are unintended. ¹ An integral time period to initiate safe and reliable contraception is in the postpartum period. This timeframe offers many advantages for women, including access to care and high motivation. ² The reasons for choosing a specific type of contraception are multi-factorial; examples include future fertility desires in the short-term and long-term periods, socioeconomic considerations, age, and marital status. The World Health Organization (WHO) and the American College of Obstetricians and Gynecologists (ACOG) have developed guidelines to assist providers and patients in contraception decision-making. ^3,4

Long-acting reversible contraception (LARC) refers to the levonogestrel intrauterine device (LNG-IUD), copper intrauterine device (Cu-IUD), and the progestin-only implant (Implant). ⁵ In the postpartum period, these methods of contraceptives offer no risk (Category 1) or the advantages of use outweigh theoretic or proven risks (Category 2). ⁶ Additionally, ACOG has initiated the Long-Acting Reversible Contraception Program which “provides information and guidance on LARC methods, specifically the contraceptive implant and IUDs, to reduce unintended pregnancy and increase women's access to the full range of contraceptive methods (pg. 1).” ⁷

The goal of our study was to determine our institution's LARC desire and initiation in the postpartum period. Our primary outcome was to determine the difference between LARC desire prior to hospital discharge and the rate at which LARC was actually utilized within 12 weeks postpartum. Secondary outcome measures included an analysis of characteristics of patients that utilized LARC and a determination of the compliance rates of the women who initiated any contraception within 12 weeks postpartum.

Methods and Materials

This investigation was approved by the Chief, Navy Bureau of Medicine and Surgery, Washington, DC, through the local institutional review board at Naval Medical Center Portsmouth (NMCP), CIP#P09-0032. We followed 400 consecutive postpartum patients discharged from our facility from January 2009 to March 2009. At the time of admission to labor and delivery, patients' inpatient medical records were used to determine initial postpartum contraception desires because this information is routinely listed on the admission history and physical paperwork. Prior to discharge, this information was confirmed by the discharge team consisting of staff and resident and intern obstetrician gynecologists.

After discharge, data was collected at 12 weeks postpartum using the global military outpatient medical record documenting system (AHLTA). Contraception utilized during this timeframe was recorded. If no postpartum visit was recorded by that time, the patient was deemed lost to follow-up. Given a population size of 4000, a sample size of 273 was required to produce a 95% confidence interval equal to the sample LARC uptake plus or minus 0.025 when the estimated LARC uptake was assumed at 0.05.

Categorical data was analyzed by chi square and Fisher's exact tests. Influence of maternal characteristics on utilization of LARC within 12 weeks postpartum was investigated using logistic regression analysis, and their effects were summarized using odds ratios (OR) and their 95% confidence interval (CI). Relative risks were calculated from the estimated ORs using the formula RR=OR/(1 − P0+P0×OR), where P0 was the probability of outcome in the reference group. ⁸ All hypotheses were considered two-sided, and p<0.05 was considered statistically significant. SPSS statistical software (version 15, SPSS Inc., Chicago, IL) was used for data analysis.

Results

Data from 400 consecutive patients were obtained at two time periods; prior to discharge from the hospital and at 12 weeks postpartum. Three hundred twenty-nine out of 400 patients had a documented postpartum visit within 12 weeks, giving an overall compliance rate of 82.3%. Three patients had become pregnant within 12 weeks postpartum, resulting in an overall pregnancy rate of 0.75%. Of those who became pregnant, one woman desired no contraception, another progestin-only pills (POP), and one LNG-IUD prior to postpartum discharge from the hospital.

Maternal characteristics of our study population are summarized in Table 1. Simultaneous factors in the immediate postpartum period associated with desire for LARC included maternal age, African-American ethnicity, and delivery via caesarean. Compared with women between ages 25 and 34, women under 25 years of age were more likely to desire LARC prior to discharge, and women 35 years of age and over were less likely to desire LARC postpartum prior to discharge. Compared to women of all other ethnicities, African-American women desired LARC more often prior to discharge. Caesarean delivery was associated with an increased likelihood of LARC desired prior to discharge but not within 12 weeks postpartum (Table 2).

Simultaneous factors predictive of LARC utilized within 12 weeks postpartum included maternal age and African-American ethnicity. Compared with women less than 25 years and women aged 25–34 years, women aged 35 years and over were less likely to utilize LARC within 12 weeks postpartum. Compared with women of all other ethnicities, African-American women were more likely to use LARC within 12 weeks postpartum (Table 2).

Amongst 329 women with data available at both time points, 36 women (10.9%) changed from LARC desired immediately postpartum to another form of contraception utilized within 12 weeks postpartum. Compared with those over age 25 years, those subjects under age 25 years had an increased likelihood of changing contraception from that initially desired within 12 weeks postpartum (16.8% vs. 7.1%, RR=2.37, 95% CI 1.28–4.11) The single factor associated with a change from desire for non-LARC contraception at discharge to LARC utilized within 12 weeks postpartum was African-American ethnicity compared to non–African-American ethnicity (10.5% vs. 4.4%, RR=2.40 95% CI 1.05–5.06).

No effects of “member status” (active duty, dependent spouse, dependent daughter) were evident with respect to contraceptive desire immediately postpartum (univariately or with adjustment for other covariates) or utilization within 12 weeks postpartum. Being a dependent spouse lowered the likelihood of desiring or utilizing LARC, but the likelihood was no longer significant when the adjustment for age and African-American ethnicity was made.

Table 3 summarizes postpartum contraceptive desire and utilization of our study population. Amongst the 132 women (33.0%) who desired LARC prior to discharge, 79 utilized LARC within 12 weeks postpartum, with 36 women switching contraception to another method. Twenty-one women who initially desired contraception other than LARC at discharge received either an IUD or Implant within 12 weeks postpartum. Of the 329 women with data on contraception received within 12 weeks postpartum, 100 women (31%) utilized LARC (88 IUDs vs. 12 Implants, 27% and 4%, respectively).

Discussion

Initiating contraception in the postpartum period offers the advantage of high patient motivation and has a profound effect on contraceptive priorities and desires. ⁹ Women have more access to their health-care provider, which allows an assessment of contraceptive needs, taking into account personal choice, sexual activity, breastfeeding patterns, menstruation, and medical and social factors. ¹⁰ Despite this access, there remain barriers to initiating postpartum contraception and close clinical follow-up in this time period is critical. ^11,12,13

In the military healthcare system, all forms of postpartum contraception are available to all patients eligible to receive care in the system without co-payment. We report 30% LARC utilization within 12 weeks postpartum. While not a perfect comparison, our utilization compares to approximately 5.5% overall LARC utilization reported in 2006–2008 National Survey for Family Growth (NSFG). ¹⁴ The reason for our high LARC utilization in this time period is not known, however, our findings may confirm that LARC becomes more appealing as the costs of initiating these forms of contraception are eliminated. ¹⁵

The identified characteristics increasing the likelihood of utilizing LARC in the postpartum period at our institution include a younger maternal age, African-American ethnicity, and cesarean delivery. Secura et al. ¹⁵ demonstrated age less than 25 years as predictive of LARC utilization when initiating a new form of reversible contraception at no cost. In contrast to their demographic analysis, we note that African-Americans were more likely to initially desire LARC at discharge and switch from non-LARC contraception to LARC within 12 weeks postpartum. While our study did not look into the reasons women desired and eventually utilized LARC, additional inquiry may add further insight into why women of certain demographics are more or less likely to choose this type of contraception in the postpartum period.

A weakness of our study may be that 71 women (18%) did not have a recorded postpartum appointment within 12 weeks after delivery. One factor unique to a military population that may impact the compliance rate is frequent relocation to new duty stations. Because several military duty stations do not offer obstetric services, patients requiring obstetric care are referred to civilian providers. This information is not available in the outpatient military documentation system and may not have captured a postpartum visit for those relocated.

Of paramount interest are those subjects who initially desired LARC prior to discharge from the hospital yet did not receive this desired contraception in the postpartum period. Despite our high LARC utilization, only 63% (77/132) of subjects who desired LARC prior to discharge were utilizing it within 12 weeks postpartum. This study did not explore the qualitative reasons for this discrepancy, but this could certainly be an area of future inquiry.

An intervention that may improve this outcome may include immediate placement of LARC prior to discharge from the hospital. Additionally, it has been suggested that a shift from the routine postpartum visit after 6 weeks to a 3-week postpartum appointment may be more appropriate to address women's contraceptive planning. ¹² This timing may also improve patient compliance and decrease the number of women lost to follow-up, particularly in our military patient population in which frequent relocation can compromise appropriate follow-up.