How Does ICP Risk Differ in Twin Pregnancies Compared With Singleton Pregnancies?

Intrahepatic cholestasis of pregnancy (ICP) is much more common in twin pregnancies than in singleton pregnancies. According to ICP Care, ICP is thought to have a hormonal cause, so the higher hormone levels in a twin pregnancy make it more likely to occur. The same source reports ICP rates of roughly 20–25% in twin pregnancies, compared with about 0.3–0.5% in singleton pregnancies. If you are pregnant with twins, this difference is worth raising with your healthcare provider so that monitoring and follow-up can be discussed.

The two numbers side by side

These figures come from ICP Care's page on twin pregnancies and ICP. They describe how often ICP is reported in each group, not a personal prediction of what will happen in your pregnancy.

Why twin pregnancies carry higher risk

ICP Care explains the difference through hormones: ICP is thought to have a hormonal cause, and a twin pregnancy involves increased levels of hormones compared with a singleton pregnancy. That higher hormonal load is the reason ICP is more likely to occur when two babies are carried.

This is a proposed mechanism rather than a complete explanation. It tells you why twin pregnancy is treated as a higher-risk situation, but it does not mean every twin pregnancy will develop ICP.

What the difference means in practice

The gap between the two rates is large — roughly one in four or five twin pregnancies versus a small fraction of singleton pregnancies. For a twin pregnancy, that makes ICP a realistic possibility to keep on the radar rather than a rare event.

Practical implications:

• Know the warning sign. ICP Care's central message is "Don't Ignore the Itch." Itching is the symptom the organization urges pregnant people not to dismiss.
• Raise your risk profile early. Because twin pregnancy is a recognized higher-risk group, mention it when discussing symptoms or monitoring with your provider.
• Use the numbers as context, not a diagnosis. A 20–25% rate describes a population, not your individual outcome. Only a healthcare provider can evaluate symptoms and order appropriate testing.

Where to go for more

ICP Care is a patient-focused organization dedicated to protecting pregnancies and families from ICP. Its site offers research-based information to download, print, and share with healthcare providers, plus a supportive online community and support groups for people diagnosed with ICP. It also runs an ICP Patient Registry that is open internationally; because ICP is a rare disease, the organization notes that more participants sharing their pregnancy journeys helps improve future care, treatment, and support.

For twin pregnancy specifically, ICP Care's article "Twin Pregnancies and Intrahepatic Cholestasis of Pregnancy" is the source of the rates above and is the natural next read if you want the full context.