Study shows benefits of taking misoprostol at home during medical abortions after 12 weeks

Pregnant people who took the first dose of misoprostol (a pill given as part of the procedure for medical abortions) at home had a 71% chance of completing their care in hospital within 9 hours with no overnight stay when having an abortion after 12 weeks of pregnancy, compared to 46% of those who took the first dose of misoprostol at hospital, finds a randomized controlled trial published in The Lancet.

A medical abortion (also known as abortion with pills) involves taking two types of pills to end a pregnancy: mifepristone, which blocks the hormone progesterone therefore causing the lining of the uterus to break down, and misoprostol, which makes the womb contract. For abortions after 12 weeks of pregnancy, mifepristone is often given at a clinic to which the patient returns one to two days later to receive a first dose of misoprostol followed by additional doses of misoprostol every few hours until the abortion is complete. In this trial, all patients received the first dose of mifepristone in the clinic as usual, but some patients then took the first dose of misoprostol at home. Previous studies indicate that most medical abortions after 12 weeks of pregnancy are completed within eight to 12 hours after the first misoprostol dose and require an average of two to three misoprostol doses, with some patients needing to stay overnight in hospital.

Currently, most abortions after 12 weeks of pregnancy take place in hospitals and may require an overnight stay, which some women find stressful and isolating. Our trial results show that taking the first dose of misoprostol at home decreases the average time women spent in hospital, enabling them to leave the hospital within nine hours after admission and without an overnight stay. Offering the choice to take the first dose of misoprostol at home provides a safe and effective alternative to taking all misoprostol doses at hospital and enables women to self-manage some of the process, potentially leading to feelings of autonomy during a time where women can feel extremely vulnerable."

Dr. Johanna Rydelius, Author, Sahlgrenska Academy, University of Gothenburg, Sweden

She adds, "Our study found 1% of the women who took misoprostol at home completed the abortion before attending hospital for the next dose. Previous studies suggest a 1% complete abortion rate within two hours after the misoprostol first dose, and women who took misoprostol at home were made aware of this risk when choosing to take part in the trial and provided with a number to call if they had any concerns. It's extremely important that women who are given the choice to take the first dose of misoprostol at home are clearly informed about the very small risk of the abortion occurring before attending the hospital."

The study took place at six hospitals in Sweden between January 2019 and December 2022. All participants were given mifepristone oral pills at an outpatient clinic and provided with a time to return. Women between 12 to 22 weeks pregnant planning to undergo a medical abortion and who chose to take part in the trial were randomised to either receive their first dose of misoprostol at home or at the hospital.

Women in the home treatment group administered the first dose of misoprostol vaginally at home and returned to hospital two hours later for the remaining treatment. Women in the hospital group self-administered the first dose of misoprostol upon arrival at the hospital. All participants then took repeated doses of misoprostol under the tongue every three hours until the abortion occurred.

Of the patients in the home treatment group, 71% (156/220) spent fewer than nine hours at hospital, compared to 46% (99/215) of those in the hospital treatment group. There was no difference in the average pain score, types and number of side effects, or rates of admittance to hospital earlier than planned between the two groups. Two patients in the home treatment group (1%) had the abortion on the way to the hospital, between one to two hours after taking the first dose of misoprostol.

The patients were asked to complete a follow up survey two to four weeks after the abortion. Five out of six participants in both trial arms (171/200 of those in the home treatment group and 152/188 of those in the hospital treatment group) said they were very satisfied with the care they received. When asked 'if you were to choose, where would you prefer to take the first dose of misoprostol?', 78% of women in the home group and 51% of women in the hospital group said they'd prefer to take the first dose of misoprostol at home.

The authors acknowledge some limitations of the study, including that the researchers were advised by the Data and Safety Monitoring Board to end the trial early due to a lower-than-expected enrolment and slow progress towards the trial's target of 784 participants. However, trial site feedback suggests the lower-than-expected enrolment rate was not due to reluctance to take misoprostol at home but rather due to patients feeling overwhelmed by the overall situation.

Every patient who seeks abortion care must navigate a unique set of personal and medical circumstances. The choice of self-administering the first dose of misoprostol at home may provide some patients with a sense of autonomy and comfort during what can be a very overwhelming time in their lives. In addition, providing the option of the first dose of misoprostol at home would enable more abortion clinics with no overnight facilities to provide medical abortions for women who are over 12 weeks pregnant, something particularly important for locations where access to abortion care is limited."

Prof. Kristina Gemzell Danielsson, The Karolinska Institutet, Sweden

Writing in a linked Comment, Heidi Moseson and Caitlin Gerdts, Ibis Reproductive Health, USA, who were not involved in the study, said: "Increasing access to abortion later in pregnancy is a crucial component of the struggle for reproductive autonomy; it requires innovation, and evidence, and a willingness to listen to the needs and experiences of people having abortions. Judging from the overwhelming preference for at-home administration of misoprostol in the PRIMA Trial, moving towards a less clinically supervised model of medical abortion care later in pregnancy is an important first step."