40 Weeks Pregnant

You are almost at the end of your pregnancy with your due date is approaching fast. While you are anticipating the start of labor any time now, it should be mentioned that only about 5% babies are born on their due date ^[1]. It is quite common, especially for first time mothers, to end up carrying their baby for a couple of weeks more, as an induction of labor is often not considered until week 42.

Baby at week 40

Sensory organs

All the five senses are developed enough by this week as your baby is ready to greet the world. His vision is still quite weak as he will not be able to make out objects located more than a few inches away. However, his sense of hearing, accompanied by his well-mature brain, allows your baby to recognize the voices of you and your partner as you talk to him after birth ^[2].

External appearance

Your baby continues to shed the greasy layer of vernix caseosa and lanugo hair, often having traces of the waxy substance and patches of downy hair on his body, along with the amniotic fluid and blood he is covered in after delivery ^[2]. However, late term babies (those born after week 41) are more likely to have relatively dry skin at birth ^[3]. Newborns also have long finger- and toenails, requiring a trimming shortly after birth ^[4].

Fetal position

The baby is all curled up in the limited space inside your womb with his arms and legs folded in front of his chest. It is quite common for newborn babies to remain in this fetal position even after birth ^[5]. This is believed to be due to the fact that after staying in this position for so long, they need a little time to adjust to having ample space for stretching out ^[2].

Infant reflexes

He has already developed all the basic skills and reflexes, such as the rooting and sucking reflexes, which will help him feed and survive after birth ^[3]. Other reflexes present at birth include the stepping, grasping and startle reflexes ^[6].

Internal organs

All his internal organs are completely mature, ready to take on their respective functions once the baby comes out of the womb. The brain and lungs are the only organs that continue developing even after your baby is born ^[7].

The baby’s liver has already stoked enough starch to begin glucose production after birth, while the fluid stored in his body helps him to make it through the first day after birth, until the breast milk is ready and available ^[8].

Your baby’s head and skull bones

The skull bones are yet to get fused together to enable them overlap and let the baby’s head pass through the birth canal easily during delivery ^[9]. Due to this reason it is quite common for babies to be born with a somewhat cone-shaped head that gradually becomes rounder over the first few weeks of life. There are also two soft spots, known as ‘fontanelles’, on his head to aid in delivery. The back fontanelle hardens within the first 3-4 months of your baby’s life, while the one at the front takes around 8 to 15 months to become hard ^[10].

How big is your baby?

The baby is about the size of a small to medium pumpkin by week 40, with his length ranging just over 20 inches (about 51 cm) ^[11], weighing around 7.6 pounds (3.45 kg) ^[12]. Boys often tend to be a little heavier than girls at birth.

Pregnancy week 40 baby position

Your baby is ready for his journey through the birth canal with his head already engaged in your pelvis. However, it is still completely normal if your baby only engages before the start of labor, especially in a second-time pregnancy ^[13].

In case of a breech position, where the baby remains in a feet down position, your doctor is likely to schedule a cesarean section in the 40th week ^[14]. However, there is still time to try and turn your baby into the proper birth position by doing pelvic tilts and kneeling exercises that involves the mother staying in an upside down position for a certain period of time so the baby can turn ^[15].

40 weeks pregnant: belly and body changes

As your baby travels down your abdomen, your bump drops a little, indicating that the day of the delivery is approaching fast. This might reduce the symptoms of heartburn, gas, appetite loss, rib pain and shortness of breath by allowing more space for the stomach and lungs to stretch. However, the increased pressure on the bladder may worsen the symptom of frequent urination.

40 weeks pregnant physical exams and tests

A Cardiotocography scan (CTG) may be ordered by your doctor or midwife to assess the baby’s health check and for any chances of complications. CTG involves monitoring the fetal muscle activity as well as the heart rate to make sure the baby is fine ^[5].

Another routine procedure this week is a pelvic exam to check whether your cervix has started dilating (opening), effacing (thinning) and softening. This helps the doctor make an estimation regarding the time for the beginning of labor ^[16]. The cervical exam also helps to decide if an induction of labor is necessary.

Your doctor will closely monitor the health of both you and your baby in case you go overdue. An ultrasound scan may be ordered to check on your baby and the placenta, as the latter may start deteriorating in case you go long beyond week 40 ^[17].

40 weeks pregnant symptoms

Round ligament pain
Braxton Hicks contractions ^[18]
Pelvic pain
Tailbone pain
Shooting pains and cramps in the legs ^[2]
Occasional tightening and sharp pain in stomach and feeling pressure in the pelvis ^[19]
Itchy skin, especially around the belly, thighs and breasts
Breast changes and leaking breasts (as they continue to produce the yellowish thick colostrum in preparation for breastfeeding)
Stretch marks
Edema or swelling of the hands, feet and ankles ^[20]
Headache and fatigue
Sore throat and hot flashes
Constipation
Joint (hips, thighs, knees, jaws), groin and back pain
Restless leg syndrome and sleep disturbances or insomnia ^[21]
Depression and emotional changes
Nesting instinct as you find ample energy to clean every corner of your house to get it ready for the baby’s arrival

40 weeks pregnant signs of labor

Watch out for the following early signs as you near your due date:

Contractions that do not go away as you change position, getting frequent over time (5 or more contractions in an hour) ^[22]
Lots of watery clear thin discharge (leaking amniotic fluid), indicating the waters breaking ^[23]
Bleeding/spotting
Increased vaginal discharge
Light brown or pinkish, bloody mucus discharge or losing the mucus plug (also referred to as bloody show)
Period-like abdominal cramps
Dull or throbbing lower back pain ^[24]
Nausea and diarrhea

40 weeks pregnant: induction of labor

Doctors generally do not go for inducing labor in the 40th week, unless there are any danger to the mother or baby, as they agree that the longer the baby stays in the womb, the lesser the chances of complications after birth ^[2]. However, an induction of labor may be necessary if it does not start on its own as you near the end of week 42 ^[25].

It may be necessary sooner in case of the following:

The water breaking or having low amniotic fluid levels for some other reason ^[26]
Developing an infectious condition possibly harmful for the baby
Risk of maternal complications such as gestational diabetes or preeclampsia ^[27]
Placental insufficiency
Suspecting any developmental problems in the baby

Natural ways to induce labor

There are a number of natural measures, including castor oil, evening primrose oil and balsamic vinegar that are believed to induce labor and are used by many women in their 39th or 40th weeks ^[28]. Eating pineapples, chocolates or spicy foods and having sex are some other measures often employed for the purpose.

While most of these measures are quite safe to apply, there is no scientific evidence for their effectiveness. It is always recommended to consult your doctor before using them to know about any possible risks to your baby. For example, having spicy foods is not scientifically proven to help labor, but it often leads to extreme heartburn and swollen ankles as they take more time to digest ^[29].

Certain herbal teas, such as red raspberry leaf tea, are believed to aid in reducing the length of labor by helping to bring on more effective contractions ^[30].

When to call the doctor

Noticing a decreased fetal movement during kick counts
Having one or more of the above signs of labor
Excessive thirst, lightheadedness and dry mouth accompanied by abnormally frequent urge to urinate, passing little urine, tiredness and nausea (might indicate gestational diabetes) ^[31]
Extreme fatigue, persistent headaches and sudden changes in vision along with upper abdominal pain, sudden swelling of the face and hands, dizziness, feeling out of breath, nausea and vomiting (might indicate high blood pressure or preeclampsia) ^[32]
Pain or burning during urination, lower back pain (around one of the kidneys), thick white or greenish yellow jelly-like discharge, dark or cloudy urine with or without a foul smell, fever, nausea, vomiting and diarrhea (might indicate a UTI ^[33] or kidney/yeast infection ^[34])
Excessive itching of the palms of the hands and soles of the feet that refuses to go away with any treatment (might indicate the liver condition obstetric cholestasis) ^[13]
Unilateral swelling or one foot or hand more swollen than the other (might indicate a blood clotting disorder)

Tips for a healthy pregnancy and baby

Making sure to launder the new baby clothes, blankets and other fabric products your baby is going to use once he comes home, as these are often treated with chemicals to preserve their color and texture; these chemicals may be harmful for your baby’s delicate skin unless washed out ^[8]
Including plenty of vitamin D in your daily diet as it aids in maintaining your bone health as well as promoting your baby’s bone growth by boosting the body’s calcium absorption properties; three daily servings of fortified soy milk, leafy vegetables and low-fat milk are recommended to get ample amount of vitamin D ^[35]
Continuing to do prenatal yoga or light exercises (e.g. going for a walk or swimming) as these help to manage the third trimester aches and pains while increasing your energy levels
Staying calm if you think you are going in labor or your waters have broken as these does not necessarily mean your baby is coming right away; in fact, doctors often ask expectant mothers to remain at home until regular contractions begin ^[3]
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