Even though about a million women a year experience a miscarriage, there is little research on complications related to pregnancy loss in the first trimester, when most miscarriages happen. The need to explore this phase is urgent, experts told ProPublica, given the way state abortion bans have disrupted maternal health care.
Although most early miscarriages resolve without complications, patients with heavy bleeding can hemorrhage if they don’t get appropriate treatment — which includes a procedure called dilation and curettage, or D&C, that is now tangled up in legislation that bans abortion. As women recounted being left to lose dangerous amounts of blood, and ProPublica told the story of a mother who died in a Houston hospital while seeking miscarriage care, reporters searched for a way to gain a broader understanding of what was happening in the state.
We consulted dozens of researchers and clinicians to develop our methodology and understand how to look at early miscarriage outcomes in the emergency department.
Our latest analysis, of hospital discharge data from Texas, found that after the state made performing abortions a felony in August 2022, the number of blood transfusions during emergency room visits for first-trimester miscarriage shot up by 54%.
The number of emergency room visits during first-trimester miscarriage also rose by 25%, a sign that women may be returning to hospitals in worse condition after being sent home, more than a dozen experts told ProPublica.
Experts say the spike is a troubling indicator of delays in care.
The most effective way to prevent severe blood loss during miscarriages, experts said, is a D&C, which uses suction to remove remaining tissue, allowing the uterus to close. The procedure is also used to terminate pregnancies.
Dr. Elliott Main, an expert on maternal hemorrhage and the former medical director for the California Maternal Quality Care Collaborative, said the increase in transfusions suggested to him that doctors working under abortion bans are now delaying those interventions for miscarrying patients for longer — “until they’re really bleeding.”
These findings add to ProPublica’s growing body of reporting revealing that maternal outcomes have gotten worse after the state’s abortion bans. In February, we published an analysis of second-trimester pregnancy loss hospitalizations, which found that the rate of sepsis climbed by more than 50% after the state banned abortion. That study focused only on inpatient stays in Texas hospitals. However, many of the clinicians and researchers we spoke with told us that that focus would limit what we could say about miscarriage care earlier in pregnancy; most people experiencing first-trimester pregnancy complications would likely be seen in a shorter emergency department visit, rather than an inpatient stay.
This methodology lays out the steps we took to examine early miscarriage outcomes in the emergency department, to help experts and interested readers understand our approach and its limitations.
Identifying First-Trimester Emergency Visits
We purchased seven years of discharge records for inpatient and outpatient encounters at hospitals and ambulatory surgery centers from the Texas Department of State Health Services. These records contain deidentified data for visits, with information about the encounter, including diagnoses recorded and procedures performed, as well as some patient demographic information and billing data.
We limited our analysis to visits with a diagnosed pregnancy loss across both the inpatient and outpatient datasets. We followed a methodology that maternal health researchers have used for many years to identify “abortive outcomes” — instances of pregnancy loss at less than 20 weeks, which includes diagnoses like ectopic pregnancy and miscarriage. Researchers have typically identified these cases in order to exclude them from metrics assessing complications in childbirth. In contrast, we focused our analysis only on those encounters with a pregnancy loss diagnosis. Medical experts suggested that it’s possible more women are self-managing abortions at home; since a self-managed medication abortion would present like a spontaneous miscarriage, however, we can’t differentiate those patients in our data.
We also limited our analysis to either emergency department visits or inpatient stays that began in the emergency department. The state’s outpatient data also includes encounters for outpatient procedures and data for ambulatory surgery centers, which we excluded to focus on emergent hospital care. Ultimately, our analysis focused on 35,500 first-trimester visits per year that came into hospitals through the emergency department, excluding a small number (about 1,400 per year) of inpatient stays that did not begin in the emergency room.
To limit our analysis to pregnancy loss in the first trimester, we looked for a diagnosis code indicating gestational weeks. In cases where a long hospitalization had multiple gestational week codes recorded over the course of the stay, we took the latest one. We excluded any row that had a gestational week code of 13 weeks or more, which marks the start of the second trimester. The vast majority — 78% — of emergency department visits for pregnancy loss had a code indicating unknown gestational week or no gestational week diagnosis code at all. We included those visits in the first-trimester category. Clinicians told us that a pregnant patient coming to the emergency department in her first trimester is less likely to have had a doctor’s appointment establishing gestational age. Since pregnancy loss in the second or third trimester is more serious, and because it is easier to establish gestational age in a pregnancy that is further along, an emergency department doctor would likely be able to establish a gestational age over the course of treatment in those cases.
We then filtered our list of visits to ones where the patient was female and between the ages of 10 and 54, to exclude rows with potential errors. This removed 2,692 visits, or 1.1% of all visits we’d identified.
The number of emergency department first-trimester hospitalizations were relatively stable prior to COVID-19. In 2022, the first full year after the state passed its six-week abortion ban, the number of encounters jumped by 11%. And in 2023, the year after the state criminalized abortion, they rose again, increasing by 25% from pre-COVID levels.
While we could identify an increase in visits, we could not identify patients across visits, which means we can’t say how many of these visits represent the same person returning to the emergency department multiple times for the same pregnancy loss. Texas has seen an increase in live births since the state banned abortion — about 2.7% in 2022, compared with the pre-COVID average, and declining slightly in 2023. But this increase in births — and, by extension, pregnancies — does not explain the rate of change in emergency visits, which far surpasses it.
Clinicians also told us that the threshold for diagnosing pregnancy loss increased after the state banned abortion. To assess how many relevant visits our analysis might be leaving out, and whether we were missing more visits after hospital policy changes, we looked for visits without a pregnancy loss code but with a diagnosis of “threatened abortion” or “early pregnancy hemorrhage,” indicating uterine cramping or bleeding in early pregnancy. Since clinicians told us that these diagnoses might range from light spotting to significant bleeding, and since bleeding in pregnancy is common and does not always indicate a miscarriage in progress, we did not include these visits in our main analysis. However, we also identified a 23% increase in visits with those codes — from an annual average of 70,936 prior to COVID to 87,431 in 2023.
Identifying Transfusions
Next, we identified pregnancy loss visits with a transfusion, which typically indicates that there has been a dangerous loss of blood.
For our inpatient dataset, where procedures performed during a hospitalization were recorded as ICD-10-PCS codes, we identified visits with a blood transfusion using a list of codes defined by the Centers for Disease Control and Prevention. The outpatient dataset, which uses Current Procedural Terminology codes, has just one code — 36430 — for blood transfusions.
Prior to COVID-19, there were 840 first-trimester pregnancy loss emergency department visits each year, on average, with a blood transfusion. In 2022, the first full year after the state passed its first abortion ban, transfusions climbed to 1,076 — an increase of 28% from pre-COVID years. By 2023, the first full year after abortion was criminalized, that number climbed to 1,290 — an increase of 54% compared to pre-COVID. That’s 450 more visits with a blood transfusion in 2023 than the pre-COVID average.
Even as the number of visits to the emergency department increased, the proportion of those visits with a transfusion also went up, from 2.5% in pre-COVID years to 2.8% in 2022 and 3% in 2023 — suggesting that the increase in transfusions may not be explained by an increase in encounters alone.
Experts who reviewed ProPublica’s data wondered if the increase in transfusions might be driven by more women experiencing complications of ectopic or molar pregnancies, rare nonviable pregnancies in which the likelihood of a blood transfusion is much higher than for a spontaneous miscarriage. The data did not bear this out. When we excluded visits with ectopic and molar pregnancy diagnoses, the increase in the number of pregnancy loss transfusions was even higher — it rose by 61% by 2023.
To understand whether there were increases in the numbers of transfusions in other maternal visits over the same time period, we also looked at blood transfusions in delivery events, using the federal methodology to identify birth complications. In hospital births, the number of transfusions increased by 6.7% in 2022 and 9.9% in 2023 compared with the pre-COVID average — an increase, but smaller in magnitude than the increase in first-trimester pregnancy loss hospitalizations.
Sophie Chou contributed data reporting.