How much can pregnant women sleep and why is oversleeping dangerous?

A moth­er’s sleep dur­ing preg­nan­cy is crit­i­cal to the well-being of the fetus. Preg­nant moth­ers are advised to sleep 7–8 hours a day. But what if you are con­stant­ly sleepy and you sleep more than 9 hours dur­ing preg­nan­cy? Is over­sleep­ing dan­ger­ous for expec­tant moth­ers? Here’s what you need to know about it.

Is it bad to sleep too long?

Hyper­som­nia is the sci­en­tif­ic term for over­sleep­ing, or exces­sive sleep. It is diag­nosed if a per­son not only sleeps at night for more than 9 hours, but also con­tin­ues to want to sleep dur­ing the day. Hyper­som­nia is psy­chophys­i­cal and patho­log­i­cal: one occurs in rel­a­tive­ly healthy peo­ple, the oth­er — under the influ­ence of drugs, neu­rot­ic dis­or­ders, men­tal trau­ma, or due to sleep apnea syn­drome.

Hyper­som­nia is dan­ger­ous in itself: accord­ing to a US study, adults who sleep more than 9 hours a day have a 50% high­er risk of dia­betes. And in women sleep­ing 9–11 hours a day, coro­nary heart dis­ease devel­ops more than 2 times.

In addi­tion, excess sleep increas­es the like­li­hood of obe­si­ty (how­ev­er, as well as lack of it) and a ten­den­cy to irri­tabil­i­ty and depres­sion.

But this is all about those who sleep too much for a long time. But what about preg­nan­cy — after all, it lasts for sev­er­al months, and far from all the time, expec­tant moth­ers man­age to sleep nor­mal­ly?

Oversleeping is a risk factor for stillbirth

Accord­ing to a recent study, US sci­en­tists have found a link between over­sleep­ing dur­ing the last month of preg­nan­cy and still­birth. The sur­vey involved 153 women who had a pre­ma­ture birth (from the 28th week). It also includ­ed 480 moth­ers who were in the third trimester of preg­nan­cy and had recent­ly giv­en birth.

Accord­ing to the data obtained, the risk of still­birth was high­er in moth­ers who slept more than 9 hours with­out wak­ing up dur­ing the last month. Pro­longed sleep with­out dis­tur­bance affect­ed the health of the fetus.

Low blood pres­sure leads to fetal prob­lems such as preterm labor and still­birth. The results showed that wak­ing up at night is a pro­tec­tive fea­ture for preg­nant moms in the third trimester — so this is a pos­i­tive side of con­stant trips to the toi­let at night.

The experts add that unin­ter­rupt­ed sleep over the past month may indi­cate a decrease in the num­ber of move­ments of the fetus: it stops wak­ing up the moth­er. Although the researchers do not elab­o­rate on this issue, you should con­sult your doc­tor if a preg­nant woman sleeps too much or the child begins to kick less.

While research links over­sleep­ing in the last month to still­birth, much is still unknown about how the auto­nom­ic ner­vous sys­tem works dur­ing this time. More research is need­ed to answer how over­sleep­ing affects bod­i­ly func­tions dur­ing preg­nan­cy.

Should I set an alarm at night?

Short answer from experts: no. Dr. O’Brien warns moth­ers against forced awak­en­ings: this can lead not only to fetal growth retar­da­tion, but also to pre­ma­ture birth.

The hor­mone prog­es­terone plays a role in mak­ing women feel too tired and sleepy in the third trimester. It is respon­si­ble for main­tain­ing a healthy preg­nan­cy, but also caus­es exces­sive fatigue and drowsi­ness. This is the most com­mon cause of drowsi­ness in the lat­er stages. How­ev­er, if some­thing seems to be going wrong, you should con­sult your doc­tor.

Other sleep disorders in the third trimester

In addi­tion to exces­sive sleepi­ness, there are oth­er sleep dis­or­ders that preg­nant women should pay atten­tion to in the last trimester.

• Insom­nia

Insom­nia is a sleep prob­lem char­ac­ter­ized by dif­fi­cul­ty falling asleep and stay­ing asleep. Phys­i­cal, hor­mon­al, meta­bol­ic, psy­cho­log­i­cal and phys­i­o­log­i­cal fac­tors can con­tribute to insom­nia in preg­nant women. Moms with insom­nia are sleep deprived and are at risk for pre­na­tal depres­sion, preeclamp­sia, ges­ta­tion­al dia­betes, pro­longed labor and cae­sare­an sec­tion. Relax­ation, lifestyle changes, exer­cise, and ther­a­py have been shown to help with insom­nia. If the con­di­tion wors­ens, you should con­sult a doc­tor.

• Obstruc­tive sleep apnea

Some moms devel­op obstruc­tive sleep dis­or­der, or sleep apnea, in the last trimester. Symp­toms of the dis­or­der include snor­ing, short­ness of breath, and dif­fi­cul­ty breath­ing. Par­tial obstruc­tion of the upper air­way dis­rupts mater­nal sleep and affects the fetus. Sleep apnea inter­feres with the flow of oxy­gen through the pla­cen­ta. This increas­es the risk of ges­ta­tion­al dia­betes, preeclamp­sia, and cae­sare­an sec­tion.

• rest­less leg syn­drome

Rest­less legs syn­drome affects one in three preg­nant women. In this state, there are pulling, aching, pul­sat­ing, crawl­ing, “elec­tric”, tick­ling sen­sa­tions. The syn­drome also caus­es an uncon­trol­lable urge to move the legs, espe­cial­ly at rest, which affects sleep.

Rest­less legs syn­drome increas­es the risk of hyper­ten­sion and preterm birth. Moms should seek med­ical atten­tion if they sus­pect they have the con­di­tion.

• Gas­troe­sophageal reflux dis­ease (GERD)

Peo­ple with GERD expe­ri­ence a burn­ing sen­sa­tion in the esoph­a­gus. The con­di­tion wors­ens when a per­son goes to bed, espe­cial­ly in the last month of preg­nan­cy: hor­mones slow down the diges­tive sys­tem and the mus­cles of the esoph­a­gus. The mus­cles then relax, and as a result, the acid moves up the esoph­a­gus, caus­ing a burn­ing sen­sa­tion. Also, as the uterus grows to accom­mo­date the fetus, it puts pres­sure on the stom­ach. Pres­sure from the stom­ach push­es acid up the esoph­a­gus.

GERD is the lead­ing cause of insom­nia among preg­nant women. For­tu­nate­ly, lifestyle choic­es can reduce the fre­quen­cy and inten­si­ty of heart­burn. About what to do in this case, read the arti­cle “Heart­burn dur­ing preg­nan­cy: how to get rid of it?”.