Pregnancy: The Fourth Month

Welcome to the so-called “quiet” months of pregnancy! The most overwhelming experience of the second trimester is feeling the baby move. Finally, you have tangible proof that you really are pregnant! Most women are very happy when they feel these movements. They can now enjoy telling people about the pregnancy. Their partner and other family members become more involved now, because pregnancy feels more “real” to them too. This is a good time to take a holiday with your partner and enjoy being pregnant.

Physical changes in the fourth month of pregnancy

This month, you will feel your clothes getting tighter. By week 16, your waistline will start disappearing. By week 17, the top of your uterus should be halfway between your pubic bone and navel. Do not try to squeeze yourself into tight clothes! Invest in some looser clothes and overalls.

This is an exciting month, because for the first time, you may be able to feel the baby move! It will start as a feeling of butterflies in your tummy. These movements are called “quickening.” Believe it or not, your baby will be fully formed by week 16.

This month, your uterus will start to rise up into the abdomen, and therefore your urinary frequency should decrease. Your nausea, if you still have it, should also diminish. Your heart is now pumping 20% more blood than usual, to supply your baby with the oxygen he requires. Your symptoms may be similar to last month’s symptoms, and could include:

  • fatigue
  • constipation
  • heartburn
  • flatulence (gas)
  • nasal congestion or nose bleeds
  • bleeding gums
  • increased appetite
  • swollen ankles
  • achy feet
  • varicose veins
  • white vaginal discharge
  • stretch marks
  • breathlessness as the baby grows larger

Heartburn is a new symptom this month. Heartburn is that burning feeling in your chest caused by acids in your stomach coming up through the esophagus. In pregnancy, hormones cause the valve at the top of the stomach to relax, which allows stomach acid to pass back into the esophagus. This is made worse by the pressure the enlarging uterus places on the stomach. Heartburn is usually worse when you are lying down. You can try to avoid heartburn by staying away from spicy or fatty foods, eating small but frequent meals, sleeping propped up in bed at night, and drinking a glass of milk before you go to bed. Your doctor may be able to recommend a suitable antacid for use in pregnancy.

The hormones in your body may also make your hair and skin quite unpredictable. Your hair may become thicker, or you might have hair loss. Dry hair could become drier, and oily hair more oily.

Your skin may be uneven in colour or texture. Some of the tiny blood vessels under your skin may become visible. These problems can usually be toned down with the use of a good concealer. Your skin may be sensitive during pregnancy, so make sure to use hypoallergenic skin care products.

Your medical visit in the fourth month of pregnancy

This month’s medical visit will be similar to last month’s. Your health care provider will check the following:

  • weight
  • blood pressure
  • size and shape of your uterus
  • height of fundus
  • urine tests for sugar and protein
  • fetal heartbeat
  • any signs of swelling in the ankles or feet, especially if accompanied by headaches, visual changes, or abdominal pain

Medical tests in the fourth month of pregnancy

A number of medical tests may be offered to you this month:

  • Ultrasound is offered in weeks 16 to 20. Ultrasound uses sound waves to make a picture of the baby in the uterus, which can be seen onscreen. Ultrasound is used to determine the fetus’s age and check for any significant abnormalities. Ultrasound can also confirm the presence of twins and the exact position of the placenta. This test is best done on a full bladder.
  • The alpha-fetoprotein (AFP) test for neural tube defects may be offered around week 16. This test is done as a follow-up to the first trimester combined screening (nuchal translucency ultrasoound and a blood test) which would have been done in weeks 11 to 13. The AFP test in week 16 checks the level of AFP in your blood. If the level is high, it could mean your pregnancy is more advanced than originally thought, that you may be carrying twins, or, rarely, that your baby may have spina bifida. If the AFP level is low, it could mean the pregnancy is not as far along as thought or, rarely, that the baby has Down syndrome. If the AFP is abnormal, you will be offered a more detailed ultrasound to look at your baby's spine.
  • Integrated prenatal screening may be offered in weeks 15 to 20 as a follow-up to initial integrated prenatal screening which would have been done in weeks 11 to 13. The first integrated prenatal screening done in weeks 11 to 13 would have consisted of a nuchal translucency ultrasound and a blood test. The integrated prenatal screening test in weeks 15 to 20 is another blood test. Integrated prenatal screening is done to determine the chances that a baby will have a chromosomal abnormality such as Down syndrome.
  • Amniocentesis tests for abnormal chromosomes in the baby. This test is offered to women who have an ultrasound or screening tests that show a possible problem with the baby. Amniocentesis is also offered to women over age 35 because they have a higher chance of having a baby with Down syndrome. A hollow needle is inserted through the abdominal wall into the uterus to draw out some amniotic fluid. The amniotic fluid is then tested for abnormalities. There is a small risk of miscarriage with this test. 

For more information, see "Prenatal Testing

Emotional changes and depression in the second trimester of pregnancy

Mood swings occur much less frequently in this trimester than in the first or third trimester. As usual, though, you may be worried about certain things. You may wonder if the pregnancy is proceeding normally and worry about injuring your baby. You may be disappointed that you can no longer control the appearance of your body, and need reassurance from your partner that you are still beautiful and sexy. You might be concerned about the consequences of becoming a mother. You may become hypercritical of your partner’s attitude, manners, and masculinity, and worry about his ability to run the household when you are unable to do so. You might even be concerned that your partner could be jealous of your pregnancy.

Depression is far less frequent in the second trimester than at any other time during pregnancy. Depression during these months is usually related to the reliving of anxieties or events of past pregnancies. For example, a woman may be depressed if she previously had a second trimester pregnancy loss. Ongoing marital problems may contribute to depression. Try to talk out any problems you may be having with your partner. Supportive psychotherapy can help too if you are feeling particularly distressed.

How your baby is developing

Nicolette Caccia, MEd, MD, FRCSC

Rory Windrim, MB, MSc, FRCSC


Nicolette Caccia, MEd, MD, FRCSC

Rory Windrim, MB, MSc, FRCSC