October 1st, 2010
12:05 AM ET

Sleep linked to hypertension in pregnant women

Pregnant women who get too much or too little sleep early in their pregnancy could develop elevated blood pressure in their third trimester, according to a new study published in the journal Sleep.

About 1,300 healthy, pregnant women participated in the study, thought to be the first to look at a link between insufficient sleep and blood pressure in pregnant women.

Researchers found women in the early stages of pregnancy typically get nine hours of sleep. But women who slept six hours or less and those who slept more than 10 hours a night had elevated blood pressure levels, the study shows.

Researchers also found a link between the amount of sleep and preeclampsia, a condition that usually occurs in the late second or third trimester and is characterized by high blood pressure and protein in the urine.

"If our results are confirmed by other studies, the findings may motivate increased efforts aimed at exploring lifestyle approaches, particularly improved sleep habits, to lower preeclampsia risk," said principal investigator and lead author Dr. Michelle A. Williams, professor of epidemiology in the School of Public Health at the University of Washington and co-director of the Center for Perinatal Studies at Swedish Medical Center in Seattle, Washington.

Not much is known about how insufficient sleep contributes to complications during pregnancy because most sleep studies don't include pregnant women, Williams notes. And she thinks that should change.

In the meantime, Williams advises pregnant women and those planning pregnancies to try to have a consistent sleep schedule, a relaxing bedtime routine and to limit eating to two to three hours before bedtime.  She also strongly encourages them to exercise regularly during the day, to avoid alcohol and caffeine before sleeping and she tells smokers to quit.

soundoff (7 Responses)
  1. kyle

    so don't sleep too much and don't sleep too little? got it. I wonder why they said not to eat 2-3 hours before bed? I know if i don't eat before bed i wake up starving to death, but that's just me. and like always of course you have to exercise and eat healthy.


    October 1, 2010 at 08:07 | Report abuse | Reply
    • Valerie

      I think it depends on what you eat. I know that a bowl of cereal in the morning is healthy, but it doesn't keep me full until lunch time. If I eat something with bread in it: a bagel, buscuit, or doughnut that I will be full until after noon. However, if I eat anything else (fruit, protein shake, etc) I can't even make it to 11:00 without starving. So I will eat the bowl of cereal before leaving the house, and something with bread in it right after I get to work. It's a much more pleasant morning that way.

      October 1, 2010 at 11:31 | Report abuse |
    • KDW

      Not sure but it may have to do with increasing risk for gestational diabetes. All women become insulin intolerant during pregnancy but some become so intolerant that they develop gestational diabetes. This happened to me. And before someone starts saying it wouldn't have happened if you had just eaten correctly exercised, I would like to share that I exercise at least 5 days a week, had a job that required a decent amount of physical activity, eat a healthy (fairly low carb) diet and only weigh 120 at 5'6". My only risk factor was that I was over the age of 25. When I had to go on the diabetic diet they told me not to eat less than two hours before bed. Your body shuts down insulin production when you sleep so if you eat right before bed you are more likely to have a spike in blood sugar.

      October 1, 2010 at 13:25 | Report abuse |
    • Summer

      @KDW Can you link me to a site that supports your claim that every woman because insulin resistant during pregnancy? I have never heard of that before and curious what even leads to that. Thank you.

      November 22, 2010 at 22:57 | Report abuse |
  2. Susan Robinson

    In your article "Sleeping and Hypertension in pregnancy, How many patients were studied? Was it a double blind study? Was there any history in the patients family of hypertension? Give more specifics in your notes, or at least a link.

    October 1, 2010 at 19:46 | Report abuse | Reply
  3. K.Jones

    Thirty days ago today, I delivered my son at 24 weeks gestation, at 1.5 ounces due to preeclampsia. Looking back, I recall sleeping a lot some days and not sleeping at all on other days. I would be interested to learn more details about this study. How many women were studied, their medical history before pregnancy, what are they concluding, etc. It's a little too late for me now but the more informed women are about the causes and consequences, the better their pregnancy experience will be.

    October 1, 2010 at 21:07 | Report abuse | Reply
  4. Dr. Dubrawsky

    Sleep,or the lack of it,is directly correlated with fluctuation in the level of H.D.L. "The good cholesterol"
    It is that,for this reason that,people wake up at 4am with heart attack,hypertnsive crisis etc.
    It is also the reason for pregnant women to wake up at 4am with labor pain.This is also,what is called in Medicine as:"The
    Morning Surge"
    Not eating in the evening or eating the:"Wrong Stuff",is a sufficient reason for what is here described>

    October 4, 2010 at 13:10 | Report abuse | Reply

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