PREGNANCY HORMONES

The following information is to be used as a guide to and at the discretion of the end-user and should not replace a doctor’s opinion.

OVERVIEW

Pregnancy is not only a time of visible physical change. From the earliest days after conception, your body begins an extraordinary hormonal shift to support your baby’s growth, prepare your uterus, protect the pregnancy, and get your body ready for birth and breastfeeding.

Hormones are chemical messengers. During pregnancy, they are produced by your ovaries, placenta, pituitary gland and other organs. The placenta becomes a powerful endocrine organ, helping coordinate changes between mother and baby.

Pregnancy hormones are powerful, purposeful and sometimes uncomfortable. They can cause nausea, tiredness, mood changes, constipation, breast tenderness, pelvic discomfort and skin changes. But they are also helping your baby grow, helping your placenta work, preparing your body for birth, and laying the foundation for breastfeeding.

WHY PREGNANCY HORMONES MATTER

Pregnancy hormones help to:

keep the pregnancy going
grow and nourish the placenta
increase blood flow to the uterus
support foetal organ development
prepare your breasts for breastfeeding
soften ligaments and joints for birth
influence mood, sleep, appetite, digestion and energy

This means good antenatal care is especially important for a healthy pregnancy and healthy baby. By monitoring your health and your baby’s development throughout your pregnancy, any complications that arise can be identified and addressed early. This is especially important during high-risk pregnancies.

THE HORMONES THAT PLAY MAJOR ROLES IN YOUR PREGNANCY

Many hormone levels are affected in the body during pregnancy. Understanding them helps make sense of early symptoms, physical adjustments, and labour. The most essential ones to know are:

1. hCG: THE EARLY PREGNANCY HORMONE

Purpose:

Human chorionic gonadotropin, or hCG, is one of the first hormones to rise after the fertilised egg implants itself in the uterus. It is the hormone detected by most pregnancy tests. hCG tells the body to continue producing progesterone and oestrogen, helping prevent menstruation and supporting early pregnancy. hCG usually rises quickly in early pregnancy, peaks around 10 weeks, and then gradually decreases.

Side effects:

hCG is linked to nausea and vomiting in early pregnancy. Morning sickness can happen at any time of day and usually starts before nine weeks. Although it often does not harm the baby, severe vomiting can affect hydration, nutrition and daily functioning, and should be discussed with a healthcare provider.
2. PROGESTERONE: THE PREGNANCY-SUPPORTING HORMONE

Purpose:

Progesterone helps maintain the pregnancy, supports placental function, and creates the environment needed for healthy foetal development. It helps thicken and maintain the uterine lining, keeps the uterus relaxed, and reducing the chance of early contractions.

Side effects:

By relaxing muscles and slowing digestion, the increase in progesterone often leads to fatigue, bloating, constipation, and heartburn. It can also trigger mood swings, breast tenderness, and headaches.
3. OESTROGEN: GROWTH, BLOOD FLOW AND PREPARATION

Purpose:

Oestrogen increases steadily during pregnancy. It helps with foetal organ development, improves blood flow to the placenta, supports growth of the uterus, and prepares the body for labour.

Side effects:

Higher oestrogen may also contribute to breast tenderness, skin changes, nasal congestion, increased vaginal discharge and emotional sensitivity. These changes can be uncomfortable, but they are usually part of normal pregnancy adaptation.
4. HUMAN PLACENTAL LACTOGEN: HELPING FEED THE BABY

Purpose:

Human placental lactogen (hPL) is produced by the placenta. It helps adjust the mother’s metabolism so that nutrients are available for the growing baby. It encourages the mother’s body to use more fatty acids for energy, helping preserve glucose for the foetus.

Side effect:

This hormone is one reason pregnancy can increase insulin resistance. For some women, this contributes to gestational diabetes, which is why antenatal screening is so important.
5. RELAXIN: SOFTENING AND STRETCHING

Purpose:

Relaxin helps relax muscles, joints and ligaments. It supports the growth of the uterus and helps prepare the pelvis and cervix for birth.

Side effects:

Because relaxin affects ligaments, some women feel pelvic discomfort, back pain, hip pain or instability. Gentle movement, good posture, supportive shoes and pregnancy-safe exercise can help, but severe pain should be assessed.
6. PROLACTIN AND OXYTOCIN: PREPARING FOR FEEDING AND BONDING

Purpose:

Prolactin helps prepare the breasts to make milk. Oxytocin helps the uterus contract during labour and supports milk let-down during breastfeeding. These hormones also play roles in bonding, calmness and recovery after birth.

Side effects:

High prolactin often contributes to fatigue and delayed menstrual cycles. Prolactin’s role in preparation for milk production can also lead to the leaking of colostrum (the first, nutrient-dense form of breast milk produced during pregnancy and the first few days after giving birth).

High oxytocin can lead to mild uterine contractions. As levels increase towards the end of pregnancy, it can cause Braxton Hicks contractions or mild cramping.

HOW HORMONES AFFECT MOOD AND EMOTIONS

Many women feel more emotional during pregnancy. Hormonal changes, sleep disruption, nausea, body changes, financial stress, relationship stress and worries about birth can all contribute. Feeling tearful or overwhelmed sometimes is common. However, persistent sadness, anxiety, panic, hopelessness or thoughts of self-harm are not something to “push through”. They need support from a midwife, doctor, clinic nurse or mental health professional.

SUPPORTING HEALTHY HORMONES DURING PREGNANCY

You cannot “balance” pregnancy hormones by force; they are meant to rise and change. The goal is to support your body while it does this work:

1. Start antenatal care early
2. Eat regularly and include protein, vegetables, fruit, whole grains and healthy fats where possible
3. Take prescribed pregnancy supplements
4. Move safely
5. Prioritise sleep and rest
6. Avoid alcohol, smoking and recreational drugs
7. Ask for help early

ARE PREGNANCY HORMONES MONITORED IN SOUTH AFRICA?

In South Africa, the primary hormone checked to confirm pregnancy is human chorionic gonadotropin (hCG). This can be done via a standard home urine test, or by a healthcare professional through a blood test.

Once pregnancy is established, doctors may selectively check other key pregnancy hormones, e.g. progesterone and oestrogen, if there are concerns about viability, bleeding, or a history of miscarriage.

WHEN TO SEEK MEDICAL CARE

While normal pregnancy hormones cause typical symptoms like fatigue, nausea, and mood swings, you should see a doctor if you experience extreme symptoms that impact your daily life, or if any red flag warning signs arise.

URGENT: Seek emergency help if you experience any of the following:

Vaginal bleeding or leaking fluid
Severe, persistent stomach or pelvic pain
Severe nausea and vomiting (unable to keep fluids down for 8-12 hours)
A noticeable decrease in the baby’s movements
Warning signs of preeclampsia, including unyielding headaches, dizziness, blurred vision, or severe swelling of the hands or face
High fever or chest pain

NON-URGENT: Make an appointment with your GP, midwife, or gynaecologist to discuss hormonal issues if you experience:

Intense, persistent emotional struggles, such as feeling depressed or constantly down
Symptoms of thyroid issues (which can be affected by pregnancy hormones), such as unusual heart palpitations or extreme, unexplained weight changes
Mild but worrying symptoms that make you feel like “something isn’t right”

PREGNANCY HORMONES

PREGNANCY HORMONES

The following information is to be used as a guide to and at the discretion of the end-user and should not replace a doctor’s opinion.

OVERVIEW

WHY PREGNANCY HORMONES MATTER

THE HORMONES THAT PLAY MAJOR ROLES IN YOUR PREGNANCY

HOW HORMONES AFFECT MOOD AND EMOTIONS

SUPPORTING HEALTHY HORMONES DURING PREGNANCY

ARE PREGNANCY HORMONES MONITORED IN SOUTH AFRICA?

WHEN TO SEEK MEDICAL CARE

FURTHER READING