What Is a Hypertonic-Saline-Induced Abortion?

Hypertonic-saline-induced abortion procedures are seldom performed today because of the health dangers tied to them.

Also known as saline abortion, hypertonic-saline-induced abortion was a method used to terminate pregnancies during the second and third trimesters.

This technique involved injecting a concentrated salt solution — hypertonic saline — into the uterus.

Although it was once a relatively common approach, clinicians now rarely perform hypertonic-saline-induced abortions due to the risks to health.

There are much safer options for terminating pregnancies after the first trimester, such as vacuum aspiration and dilation and evacuation (D&E). These contemporary methods are typically quicker and cause less physical distress.

While older techniques like saline instillation are considered hazardous, the abortion methods commonly used today are widely regarded as very safe and effective.

When was this method used and what was its intent?

Obstetrician Eugen Aburel developed hypertonic-saline-induced abortion in 1939. It was most frequently performed between roughly the 16th and 24th weeks of gestation.

Saline abortion is a type of instillation abortion. Instillation procedures involve introducing a solution into the pregnancy. Other instillation approaches historically used substances such as urea or prostaglandins.

Research indicates saline instillation became popular in many regions during the mid-20th century, particularly in the 1960s. A 1972 report showed that 28% of legal abortions in San Francisco in 1968 were saline instillations.

Nowadays, all types of instillation abortions are uncommon. In 1972 they represented 10.4% of legal abortions in the United States; by 1985 that proportion had fallen to 1.7%.

According to the Centers for Disease Control, 241 instillation abortions were recorded in 2020, comprising about 0.04% of all abortion procedures that year.

How was the procedure done?

The hypertonic-saline-induced abortion typically required 24–30 hours on average, though it could extend beyond that. The procedure was performed in hospital settings.

There were two primary variations of saline instillation abortions: intra-amniotic and extra-amniotic.

Intra-amniotic instillation meant introducing the saline into the amniotic sac, while extra-amniotic instillation involved placing the solution between the fetal membranes and the endometrium.

Intra-amniotic hypertonic-saline-induced abortions commonly followed these steps:

1. The person emptied their bladder and sometimes received an enema.
2. A clinician sterilized the abdomen and administered a local anesthetic.
3. A spinal needle was inserted into the amniotic sac.
4. The saline solution was delivered into the amniotic cavity through the needle.
5. The fetal tissue experienced necrosis.
6. The person went into labor and expelled the pregnancy tissue.

Extra-amniotic hypertonic-saline-induced procedures typically proceeded like this:

1. The person emptied their bladder and sometimes had an enema.
2. A clinician inserted a device through the vaginal canal up into the cervix.
3. The solution was instilled through that device.
4. Tissue death occurred.
5. The person went into labor and delivered the pregnancy tissue.

In both approaches, the total time depended on how long labor lasted. Other influencing factors included:

• the volume of saline used
• the concentration of the saline solution
• whether amniotic fluid was removed beforehand
• whether adjunctive medications like oxytocin or prostaglandin were administered
• whether Laminaria tents — devices used to promote contractions — were employed

Why did clinicians stop using this method?

As alternative abortion techniques became more widespread, hypertonic-saline-induced abortions declined because they were more hazardous, more complicated, and less reliable than newer options.

Between 1972 and 1981, instillation methods had a higher mortality rate compared with D&E procedures.

During that period, instillation techniques were linked to 9.6 deaths per 100,000 procedures, while D&E methods had a mortality rate of 4.9 per 100,000.

By 2019, the mortality rate for all legal abortion procedures was about 4 per 100,000; most of those deaths were associated with illegal services.

Compared with other approaches, saline abortions:

• carried a higher likelihood of serious complications
• required more time to complete, often necessitating overnight hospitalization
• caused greater physical discomfort
• were less reliable, with a higher chance the pregnancy would continue despite the procedure

The health hazards associated with hypertonic-saline-induced abortion included:

• hypernatraemia (excessive salt in the bloodstream)
• water intoxication
• severe hemorrhage
• seizures
• coma
• death

For these reasons, safer techniques such as vacuum aspiration and D&E largely replaced saline instillation methods.

Which abortion methods are used now?

Today, three main types of abortion are most commonly used:

• Medication abortion: Typically performed in the first trimester, this approach uses misoprostol (and frequently mifepristone) to end a pregnancy.
• Vacuum aspiration: An in-clinic procedure in which pregnancy tissue is evacuated through the cervix using gentle suction.
• Dilation and curettage (D&C) / Dilation and evacuation (D&E): In-clinic procedures that widen the cervix so pregnancy tissue can be removed manually; sometimes referred to as dilation and extraction.

All of these contemporary abortion methods are deemed highly safe and effective. Complications are uncommon, affecting fewer than 2% of patients who undergo abortion.

Where can you find more information and help?

Modern abortion practices are considerably safer and more effective than hypertonic-saline-induced instillation methods.

If you want to explore your options, the following resources may be useful:

• Understanding Abortion Restrictions in Your State
• How to Safely Self-Manage a Medication Abortion at Home
• What to Expect with Later-Term Abortion

You can also get assistance from these organizations:

• Abortion Finder, the National Abortion Federation, and Planned Parenthood can help locate local abortion care services.
• The Center for Reproductive Rights’ state-by-state map provides details about abortion laws and access across U.S. states.
• The National Network of Abortion Funds offers guidance on finding financial assistance for abortion care.

When seeking pregnancy- or abortion-related help, be cautious of crisis pregnancy centers.

Despite appearing as legitimate clinics, many of these centers are unregulated, unlicensed, and often backed by anti-abortion groups.

They frequently provide inaccurate or misleading information intended to dissuade people from seeking abortion. One study found that 80% of crisis pregnancy centers disseminated misleading claims.