In every pregnancy, a woman starts out with a 3-5% chance of having a baby with a birth defect. This is called her background risk. This sheet talks about whether exposure to ­­­­­laxatives may increase the risk for birth defects over that background risk. This information should not take the place of medical care and advice from your health care provider.

What are laxatives?
Medications used to treat constipation are called laxatives. Many are available over-the-counter, and there are several different forms. Osmotics work by pulling water into the intestines. Since they are not well- absorbed by the intestine, very little gets into the blood which means exposure to the pregnancy would be small. Examples of osmotics include salts, such as magnesium hydroxide (Milk of Magnesia®) and sodium bisphosphate (OsmoPrep®), sugars, such as lactulose and polyethylene glycol (Miralax®).

Fiber or bulk laxatives include psyllium (Metamucil®), methylcellulose (Citrucel®), and lactulose. Since they generally do not get into the blood, pregnancy exposure is unlikely.

Stool softeners include docusate sodium (Colace®) and glycerin. For more information, please see the MotherToBaby fact sheet Docusate Sodium and Pregnancy at http://mothertobaby.org/fact-sheets/docusate-sodium-pregnancy/pdf/.

Stimulants, such as Senna (Senokot®) and Bisacodyl (Correctol®), may enter the blood in small amounts so there may be small exposure to the pregnancy. Castor oil, also a stimulant, is made from the seeds of castor beans. These products may have the side effect of causing stomach cramps. Mineral oil is a lubricant. It can cause heavy cramping and some does get into the blood.

I just found out I am pregnant. Should I stop taking a laxative?
You should always talk with your health care provider before making any changes in your medication. It is important to consider the benefits of treating constipation symptoms during pregnancy.

Constipation may cause pain and other health problems in pregnancy such as cramps, hemorrhoids, and breakdown of the anal tissue. Treating constipation will help reduce the risk of these problems. Dietary changes such as increasing fluids, eating high fiber foods such as whole grains and fresh fruits and vegetables can help prevent constipation. Regular exercise can also help. Although occasional constipation is common in pregnancy, talk with your health care provider if constipation becomes an ongoing problem. Your health care provider may also want to confirm the diagnosis of constipation and see how dietary changes may help before discussing medical treatment.

Can the use of laxatives during pregnancy cause birth defects?
Few studies have been done to look at the possible risks of laxatives during pregnancy. However, the available studies show that when used in recommended doses, laxatives are not expected to increase the risk of birth defects or pregnancy problems.

Are there other concerns when using laxatives?
Yes. Laxatives may reduce the amount of nutrition and medicines that get into the blood since laxatives can make food go through the intestines faster than usual. Nutritional problems are only seen when these agents are used more than recommended.

When more than the recommended amounts of laxatives are used, some can also lower the levels of salts, such as magnesium, in a person’s blood. There is one reported case of low magnesium levels in a newborn that was linked to the mother using too much docusate sodium. The baby’s main symptom was jitteriness, which went away by the second day of life.

Castor oil has been used at the end of pregnancy to bring on labor. It can cause severe diarrhea and cramping of the bowel and uterus. However, if the lower part of the uterus (cervix) is not ready, these contractions will not bring on labor. If you are at the end of your pregnancy, your health care provider can discuss other ways to begin labor.

Can I use laxatives while breastfeeding?
While some of the medications may get into the blood of the mother, the amount that passes into milk is usually low. However, mineral oil can get into the blood and mother’s milk in greater amounts, so it should be used carefully. Other options may be a better choice.

There are occasional reports of infants with loose stools when the mother uses laxatives. There have been no reports of problems in babies that are breastfeeding while the mother is using recommended doses of laxatives. Be sure to talk to your health care provider about all your choices for breastfeeding.

What if the father of the baby uses laxatives?
There are no studies looking at possible problems with conceiving or risks to a pregnancy when the father takes laxatives. In general, exposures that fathers have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures and Pregnancy at http://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/pdf/.

Selected References:

  • Acs N, Binhidy F, et al. 2009. Senna treatment in pregnant women and congenital abnormalities in their offspring- a population-based case-control study. Reproductive Toxicology Jul; 28(1):100-104.
  • Avery GS, Davies EF, et al. 1972. Lactulose: a review of its therapeutic and pharmacologic properties with particular reference to ammonia metabolism and its mode of action in portal systemic encephalopathy. Drugs 4:7-48.
  • Baldwin WF. 1963. Clinical study of senna administration to nursing mothers: assessment of effects on infant bowel habits. Canadian Medical Association Journal 89:566-568.
  • Concin N, Hofstetter G, Plattner B, et al. 2008. Mineral oil paraffins in human body fat and milk. Food and Chemical Toxicology 46(2):544-552.
  • Danhof IE. 1982. Pharmacology, toxicology, clinical efficacy, and adverse effects of calcium polycarbophil, an enteral hydrosorptive agent. Pharmacotherapy 2:18-28.
  • Friedrich C, Richter E, et al. 2011. Lack of excretion of the active moiety of bisacodyl and sodium picosulfate into human breast milk: an open-label, parallel group, multiple dose study in healthy lactating women. Drug Metab Pharmacokinet 26(5):458-464.
  • Gattuso JM, Kamm MA. 1994. Adverse effects of drugs used in the management of constipation and diarrhoea. Drug Safety 10:47-65.
  • Hagemann TM. 1998. Gastrointestinal medications and breastfeeding. Journal of Human Lactation 14:259-262.
  • Rude RK, Singer FR. 1981. Magnesium deficiency and excess. Annual Review of Medicine 323:245-259.
  • Schindler AM. 1984. Isolated neonatal hypomagnesaemia associated with maternal overuse of stool softener. Lancet 2:822.
  • The WHO Working Group, Bennet PN (ed). 1988. Drugs and Human Lactation. Elsevier, Amsterdam, New York, Oxford, 88-89.
  • Trottier M, Erebara A, et al. 2012. Treating constipation during pregnancy. Canadian Family Physician 58, 836-838.
  • Werthmann MW, Jr., Krees SV. 1973. Quantitative excretion of Senokot in human breast milk. The Medical Annals of the District of Columbia 42(1):4-5.