Gallstones and Cholecystitis in Pregnancy

Why pregnancy makes gallstones more likely

Two changes work together. Progesterone relaxes smooth muscle throughout the body, including the gallbladder wall, so the gallbladder empties less completely and bile sits for longer. Oestrogen increases the cholesterol saturation of bile. Bile that is more concentrated and sitting still is bile that forms stones.

The result is that gallstones are found more often during and shortly after pregnancy than at other times, and that stones which were present and silent before pregnancy are more likely to start causing symptoms.

Telling the two conditions apart

The distinction matters because it changes the urgency.

Biliary colic is pain from a stone temporarily blocking the outlet of the gallbladder. The NHS describes gallstone pain as "sudden and intense pain in the upper right part of your tummy", which can also be felt in the centre of the abdomen or spread to the right shoulder blade, often after eating fatty food. It typically lasts from a few minutes to a few hours and then settles completely.

Acute cholecystitis is inflammation or infection of the gallbladder, and it does not settle. The NHS describes it as causing severe pain in the upper right abdomen that spreads to the right shoulder, with the pain persisting rather than passing, usually with a high temperature and feeling generally unwell.

The practical rule is duration and fever. Pain that goes away completely within a few hours is more likely colic; pain that persists for many hours with a temperature needs same-day assessment.

Why upper abdominal pain in pregnancy is never a small thing

Pain in the upper right abdomen in the second half of pregnancy is one of the classic warning signs of pre-eclampsia and of HELLP syndrome, and it can also be caused by obstetric cholestasis, appendicitis in a displaced position, or a duodenal ulcer.

That is why this symptom always gets a blood pressure check and blood tests as well as an ultrasound, and why you should never assume a known gallstone is the explanation. Tell whoever assesses you that you are pregnant and how many weeks, so that the obstetric causes are excluded rather than assumed away.

The scans, and what is safe

NICE guideline CG188 sets the first step: "Offer liver function tests and ultrasound to people with suspected gallstone disease." Ultrasound is the primary test and it involves no radiation, so it is used freely in pregnancy.

Where a stone is suspected in the bile duct rather than the gallbladder, CG188 says to "consider magnetic resonance cholangiopancreatography (MRCP) if ultrasound has not detected common bile duct stones but the bile duct is dilated and/or liver function test results are abnormal", and to "consider endoscopic ultrasound (EUS) if MRCP does not allow a diagnosis to be made". MRI-based imaging does not use ionising radiation.

One thing to know about the blood results: alkaline phosphatase rises normally in pregnancy because the placenta produces it, so an isolated raised ALP is not evidence of a bile duct problem. Interpretation uses the other liver enzymes and bilirubin alongside it.

What happens if it is cholecystitis

Outside pregnancy, NICE CG188 is clear: "Offer early laparoscopic cholecystectomy (to be carried out within 1 week of diagnosis) to people with acute cholecystitis." In pregnancy, that recommendation is applied with obstetric input rather than ignored.

Initial management of acute cholecystitis is usually admission, nil by mouth, intravenous fluids, pain relief and antibiotics. Where symptoms settle, the decision is then whether to operate during the pregnancy or wait until after birth.

Repeated attacks, failure to settle, or complications tend to push towards surgery during pregnancy, and laparoscopic cholecystectomy is performed in pregnancy when needed. The second trimester is generally the preferred window for planned abdominal surgery. Where surgery is deferred, expect a plan for what to do if the pain returns, and a referral for the operation after birth — CG188 recommends laparoscopic cholecystectomy for symptomatic gallbladder stones.

Asymptomatic stones found incidentally need nothing. CG188: "Reassure people with asymptomatic gallbladder stones found in a normal gallbladder and normal biliary tree that they do not need treatment unless they develop symptoms."

Managing between attacks

The practical measure is dietary. Fatty meals trigger gallbladder contraction, and reducing fat intake reduces the frequency of attacks for many people. This is not a cure and it does not dissolve stones, but it can make the weeks until delivery or surgery considerably more bearable.

Do this without cutting your overall intake in pregnancy. Eating too little is its own problem, and a dietitian referral is reasonable if you find yourself avoiding food to avoid pain. Keeping well hydrated and eating smaller, more frequent meals is generally easier than three large ones.

When to go in

Seek same-day assessment for pain lasting more than a few hours, a temperature, repeated vomiting, yellowing of the eyes or skin, pale stools or dark urine. Jaundice suggests a stone in the bile duct rather than the gallbladder, which is a different and more urgent problem.

Also seek assessment for any severe upper abdominal pain after 20 weeks regardless of what you think is causing it, because pre-eclampsia has to be excluded. Your routine antenatal care under NICE guideline NG201 continues alongside all of this.

The other stone complications

Two further problems are worth knowing by name, because they change the urgency. A stone that lodges in the bile duct causes obstructive jaundice: yellowing of the eyes and skin, pale stools, dark urine and itching. Where infection develops in the obstructed duct, ascending cholangitis follows, with fever and rigors added, and it is a medical emergency.

Gallstone pancreatitis is the other. It causes severe upper abdominal pain that bores through to the back, usually with persistent vomiting, and it needs immediate hospital assessment. NICE guideline CG188 covers bile duct clearance for common bile duct stones, offering "bile duct clearance and laparoscopic cholecystectomy to people with symptomatic or asymptomatic common bile duct stones".

Itching without a rash deserves particular mention in pregnancy, because it is also the cardinal symptom of obstetric cholestasis, a specifically obstetric liver condition unrelated to gallstones. Itching in pregnancy should always be reported to your midwife rather than attributed to stones you already know about.