Accuracy of Gestational Age Estimated by Menstrual Dating in Women Seeking Abortion Beyond Nine Weeks

Short-Term Adverse Outcomes After Mifepristone-Misoprostol Versus Procedural Induced Abortion : A Population-Based Propensity-Weighted Study

BACKGROUND

Prior studies comparing first-trimester pharmaceutical induced abortion (IA) with procedural IA were prone to selection bias, were underpowered to assess serious adverse events (SAEs), and did not account for confounding by indication. Starting in 2017, mifepristone-misoprostol was dispensed at no cost in outpatient pharmacies across Ontario, Canada.

OBJECTIVE

To compare short-term risk for adverse outcomes after early IA by mifepristone-misoprostol versus by procedural IA.

DESIGN

Population-based cohort study.

SETTING

Ontario, Canada.

PATIENTS

All women who had first-trimester IA.

MEASUREMENTS

A total of 39 856 women dispensed mifepristone-misoprostol as outpatients were compared with 65 176 women undergoing procedural IA at 14 weeks' gestation or earlier within nonhospital outpatient clinics (comparison 1). A total of 39 856 women prescribed mifepristone-misoprostol were compared with 8861 women undergoing ambulatory hospital-based procedural IA at an estimated 9 weeks' gestation or less (comparison 2). The primary composite outcome was any SAE within 42 days after IA, including severe maternal morbidity, end-organ damage, intensive care unit admission, or death. A coprimary broader outcome comprised any SAE, hemorrhage, retained products of conception, infection, or transfusion. Stabilized inverse probability of treatment weighting accounted for confounding between exposure groups.

RESULTS

Mean age at IA was about 29 years (SD, 7); 33% were primigravidae. Six percent resided in rural areas, and 25% resided in low-income neighborhoods. In comparison 1, SAEs occurred among 133 women after mifepristone-misoprostol IA (3.3 per 1000) versus 114 after procedural IA (1.8 per 1000) (relative risk [RR], 1.87 [95% CI, 1.44 to 2.43]; absolute risk difference [ARD], 1.5 per 1000 [CI, 0.9 to 2.2]). The respective rates of any adverse event were 28.9 versus 12.4 per 1000 (RR, 2.33 [CI, 2.11 to 2.57]; ARD, 16.5 per 1000 [CI, 14.5 to 18.4]). In comparison 2, SAEs occurred among 133 (3.4 per 1000) and 27 (3.3 per 1000) women, respectively (RR, 1.04 [CI, 0.61 to 1.78]). The respective rates of any adverse event were 31.2 versus 24.9 per 1000 (RR, 1.25 [CI, 1.04 to 1.51]).

LIMITATION

A woman prescribed mifepristone-misoprostol may not have taken the medication, and the exact gestational age at IA was not always known.

CONCLUSION

Although rare, short-term adverse events are more likely after mifepristone-misoprostol IA than procedural IA, especially for less serious adverse outcomes.

PRIMARY FUNDING SOURCE

Canadian Institutes of Health Research.

Accuracy of self-assessment of gestational duration among people seeking abortion

BACKGROUND

Mifepristone, used together with misoprostol, is approved by the United States Food and Drug Administration for medication abortion through 10 weeks' gestation. Although in-person ultrasound is frequently used to establish medication abortion eligibility, previous research demonstrates that people seeking abortion early in pregnancy can accurately self-assess gestational duration using the date of their last menstrual period.

OBJECTIVE

In this study, we establish the screening performance of a broader set of questions for self-assessment of gestational duration among a sample of people seeking abortion at a wide range of gestations.

STUDY DESIGN

We surveyed patients seeking abortion at 7 facilities before ultrasound and compared self-assessments of gestational duration using 11 pregnancy dating questions with measurements on ultrasound. For individual pregnancy dating questions and combined questions, we established screening performance focusing on metrics of diagnostic accuracy, defined as the area under the receiver operating characteristic curve, sensitivity (or the proportion of ineligible participants who correctly screened as ineligible for medication abortion), and proportion of false negatives (ie, the proportion of all participants who erroneously screened as eligible for medication abortion). We tested for differences in sensitivity across individual and combined questions using McNemar's test, and for differences in accuracy using the area under the receiver operating curve and Sidak adjusted P values.

RESULTS

One-quarter (25%) of 1089 participants had a gestational duration of >70 days on ultrasound. Using the date of last menstrual period alone demonstrated 83.5% sensitivity (95% confidence interval, 78.4-87.9) in identifying participants with gestational durations of >70 days on ultrasound, with an area under the receiver operating characteristic curve of 0.82 (95% confidence interval, 0.79-0.85) and a proportion of false negatives of 4.0%. A composite measure of responses to questions on number of weeks pregnant, date of last menstrual period, and date they got pregnant demonstrated 89.1% sensitivity (95% confidence interval, 84.7-92.6) and an area under the receiver operating curve of 0.86 (95% confidence interval, 0.83-0.88), with 2.7% of false negatives. A simpler question set focused on being >10 weeks or >2 months pregnant or having missed 2 or more periods had comparable sensitivity (90.7%; 95% confidence interval, 86.6-93.9) and proportion of false negatives (2.3%), but with a slightly lower area under the receiver operating curve (0.82; 95% confidence interval, 0.79-0.84).

CONCLUSION

In a sample representative of people seeking abortion nationally, broadening the screening questions for assessing gestational duration beyond the date of the last menstrual period resulted in improved accuracy and sensitivity of self-assessment at the 70-day threshold for medication abortion. Ultrasound assessment for medication abortion may not be necessary, especially when requiring ultrasound could increase COVID-19 risk or healthcare costs, restrict access, or limit patient choice.

Non-use of Contraception by Canadian Youth Aged 15 to 24: Findings From the 2009-2010 Canadian Community Health Survey

OBJECTIVES

Non-use of contraception is an important contributor to unintended pregnancy. This study assessed non-use of contraception and its determinants among Canadian youth aged 15 to 24.

METHODS

Data from the 2009-2010 Canadian Community Health Survey respondents aged 15 to 24 were used to identify non-users of contraception among heterosexual youth who had had intercourse within the previous 12 months, were not pregnant or sterilized, and felt it was important to avoid pregnancy. Sociodemographic, behavioural, and geographic factors were compared for non-users and users of contraception.

RESULTS

Among youth at risk for unintended pregnancy, 15.5% were non-users of contraception. There were no differences between sexes. Across regions of Canada, Quebéc had the highest proportion of at-risk youth, but at-risk Quebéc youth were the least likely to be non-users (7.4%; CI 5.7%-9.0%) compared with at-risk youth in the Territories (28.3%; CI 21.6%-35.0%). In the multivariable analysis, aside from residence outside of Quebéc, younger age, lower income, Aboriginal identification (adjusted OR [aOR] 1.67; CI 1.18-2.37), and smoking (aOR 1.55; CI 1.24-1.92) were associated with non-use. Canadian-born youth (aOR 0.61; CI 0.39-0.96) and those enrolled in school (aOR 0.63; CI 0.50-0.81) were less likely to be non-users.

CONCLUSION

The 15.5% of Canadian youth at risk for unintended pregnancy who were non-users of contraception represent an estimated 300 000 Canadian youth. Policies and programs to promote and support access to sexual health services and effective contraception with specific attention to supporting the needs of younger teens, Aboriginal youth, newcomers, low-income youth, and youth who are not in school are needed.

Accuracy of gestational age estimation from last menstrual period among women seeking abortion in South Africa, with a view to task sharing: a mixed methods study

BACKGROUND

The requirement for ultrasound to establish gestational age among women seeking abortion can be a barrier to access. Last menstrual period dating without clinical examination should be a reasonable alternative among selected women, and if reliable, can be task-shared with non-clinicians. This study determines the accuracy of gestational age estimation using last menstrual period (LMP) assessed by community health care workers (CHWs), and explores providers' and CHWs' perspectives on task sharing this activity. The study purpose is to expand access to early medical abortion services.

METHODS

We conducted a multi-center cross-sectional study at four urban non-governmental reproductive health clinics in South Africa. CHWs interviewed women seeking abortion, recorded their LMP and gestational age from a pregnancy wheel if within 63 days. Thereafter, providers performed a standard examination including ultrasound to determine gestational age. Lastly, investigators calculated gestational age for all LMP dates recorded by CHWs. We compared mean gestational age from LMP dates to mean gestational age by ultrasound using t-tests and calculated proportions for those incorrectly assessed as eligible for medical abortion from LMP. In addition, in-depth interviews were conducted with six providers and seven CHWs.

RESULTS

Mean gestational age was 5 days (by pregnancy wheel) and 9 days (by LMP calculation) less than ultrasound gestational age. Twelve percent of women were eligible for medical abortion by LMP calculation but ineligible by ultrasound. Uncertainty of LMP date was associated with incorrect assessment of gestational age eligibility for medical abortion (p = 0.015). For women certain their LMP date was within 56 days, 3% had ultrasound gestational ages >70 days. In general, providers and CHWs were in favour of task sharing screening and referral for abortion, but were doubtful that women reported accurate LMP dates. Different perspectives emerged on how to implement task sharing gestational age eligibility for medical abortion.

CONCLUSIONS

If LMP recall is within 56 days, most women will be eligible for early medical abortion and LMP can substitute for ultrasound dating. Task sharing gestational age estimation is feasible in South Africa, but its implementation should meet women's privacy needs and address healthcare workers' concerns on managing any procedural risk.