Hormones in Pregnancy & Post-Partum: How they can affect your fitness and well-being journey.

Hormones in Pregnancy & Post-Partum: How they can affect your fitness and well-being journey.

The journey of a woman throughout pregnancy is thrilling and full of joy but there can also be lows as our female hormones experience a shift. Pregnancy is a time of immense change within your body and, even before you know that you are pregnant,you will find yourself crying over your favourite soap opera and, a minute later, feel incandescent with rage when you realise that your partner ate the last piece of toast again…that is all thanks to a potent cocktail of chemicals called hormones! From day one, hormones will make you feel as if you are riding a never-ending roller coaster. Just imagine the anticipation rising with every click and clack up the lift before the slight euphoria as the car reaches the top. From there on in, you start your journey, with negatives and positive feelings racing one after the next.

“Hormonal changes are normal during pregnancy. They indicate that your body is being prepared for the development of your beautiful baby.”

For the next 40 weeks of pregnancy, your hormones will act as the body’s chemical messengers transporting important information between different tissues and organs.Attached to the protein of the receptor cells, the hormones travel around the body via the circulatory system targeting these tissues or organs causing them to change their function and create a susceptible environment for a successful pregnancy.Following this process, you will notice significant changes in the way you perceive the world through the senses of smell, sight and taste. Furthermore, there will be significant changes in heart and kidney functions, increase in body fat as well as physiological changes to the uterus, breasts and joints. Mood swings, changes in your sense of balance and the way you move are also part of the process.To understand how hormones affect your body during each trimester and beyond, it is important to clarify their importance and how they participate in the growth of your baby. So get set for a journey of discovery about the most important hormones that get the baby ball rolling, so to speak, and then prepare your body for labour and delivery.

According to the website,, the most important hormones at playduring pregnancy are:

●HCG – Human Chorionic Gonadotropin
●HPL – Human Placental Lactogen
●FSH – Follicle Stimulating Hormone
●LH – Luteinizing Hormone
●Placental Growth Factor

Below is detailed information on how each hormone acts in your body during your pregnancy.

HCG – Human Chorionic Gonadotropin

This hormone is highly present in the first trimester, preparing the womb for the embryo to form. It reaches its peak at around 60-90 days then levels off for the remainder of the pregnancy. HCG is eliminated in the urine and its high concentration is what triggers the over-the-counter pregnancy tests, to indicate the beginning of a new life form in your body.

HPL – Human Placental Lactogen

Also called Human Chorionic Somatomammotropin, this hormone is produced in the placenta within the first two weeks of gestation and plays a key role in the regulation of your metabolism and insulin resistance. It assists in the efficiency of the breakdown of fat from foods and freeing up glucose – sugar – to be used as energy and to nourish the fetus. It is also believed that this hormone supports the lactation
process and preparation for breastfeeding but more research is still required to confirm this theory.

Your doctor may ask you to have your HPL tested if you show symptoms like an atypical ultrasound or an issue with the placenta, potential miscarriage, if the proportion of amniotic fluid surrounding the fetus drops or if you are susceptible of developing gestational diabetes. The test is done as a simple blood test and you can always ask your doctor to clarify the reasons if the test is required.

FSH – Follicle Stimulating Hormone

Produced by the pituitary gland in the brain, FSH is present even before you conceive and is responsible for the management of your monthly cycles and, also the growth of eggs. During the production of eggs, the level of estrogen raises stimulating another hormone – luteinizing hormone – to assist in ovulation and potentially in the pregnancy.

LH – Luteinizing Hormone

As FSH, LH is produced in the pituitary gland in the brain and they work together on the management of your menstrual cycle. When estrogen levels are high, LH has the job to break apart the ovaries follicles and release an egg from your ovary. Once in the fallopian tube, the egg together with the follicles is called the corpus luteum and if this encounters a sperm, your body will continue the production of the necessary hormones for the development of your baby. If not, your body will naturally eliminate the corpus luteum after 14 days.

Placental Growth Factor

PLGF is mostly produced in the placenta but can also be found at low levels in other organs in the body. According to the Journal of Human Hypertension,the function of PLGF in the placenta is likely to be in the promotion of development and maturation of the placental vascular system. It boosts the blood vessels to grow and support the raised blood volume needed to feed your growing baby.

If the levels for this hormone are low, you may show signs of pre-eclampsia which can be very dangerous for you and your baby. Pre-eclampsia is a condition believed to start in the placenta due to failure of the blood vessels. The main symptoms are high blood pressure and protein in the urine. If untreated, your baby may be depleted of oxygen and essential nutrients, and you may suffer serious complications or even be fatal.


Estrogen is a female hormone responsible for the female gender characteristics and support of the reproductive system. It is produced by the ovaries, fat tissue and adrenal glands and, together with progesterone, has various functions during the pregnancy. This hormone rises once the fertilization is completed allowing the uterus and the placenta to generate new blood vessels and nurture your baby. Often the morning sickness in the first trimester and swollen feet and hands in the third trimester are linked to the rise of estrogen in the system. It also assists with the maintenance and control of other key pregnancy hormones including oxytocin release during the labour, stimulates the correct growth of the placenta and expansion of the uterus, triggers the development of your baby’s organs and helps with preparing your breasts for lactation by promoting growth of the breast tissue.


Progesterone is produced in the ovaries after ovulation. It is the second most important hormone as it plays an important part, together with estrogen, in the fertilization and settling of the embryo in the uterus. Throughout the pregnancy, this hormone helps the uterus to grow and stops it from contracting (which may cause miscarriage) until the onset of labour. It also prevents lactation until after birth and works together with relaxin in preparation of labour by softening the ligaments and loosening your joints. This partnership can often cause symptoms like heartburn, indigestion, constipation and bloating.


During the first trimester, many mums experience pain and discomfort in the pelvis and lower back which is mainly caused by the increase of relaxin. This hormone supports the enlargement of the hip and pelvic area to accommodate the growing baby and relaxes your muscles, joints and ligaments which may lead to poor balance and reduce stability.


Vital to labour and delivery of your baby, this hormone is well known for stimulating labour contractions and assists in the transport of milk to the nipple for breast feeding. It is produced by the hypothalamus and secreted by the pituitary gland and, once your baby is born, it also helps with the control of bleeding after birth by reducing blood flow to the womb, to detach the placenta afterwards and with bonding between you and your newborn.


As the name says, Prolactin (lac = lactation) has the job to assist in the enlargement of the breast and production of breast milk to feed your baby. When teamed up with the Oxytocin and beta-endorphins (a natural pain relief hormone released during labour), Prolactin also encourages the beautiful bonding between you and your baby.

and there is more…

Among these amazing hard-working hormones, there are a few others that will actively participate on the process such as;insulin which controls the metabolism of the food you eat and what goes to the baby; calcitonin, erythropoietin and cortisol which are responsible for bone growth, and regulate the production of red blood cells and help with baby’s lung development, respectively. Also, high levels of vasopressin and    adrenocorticotropic hormones may lead to water retention,stretch marks and swelling.

You can now finally meet and hold your bundle of joy! You are nearly at the end of your rollercoaster ride. Adrenaline and noradrenaline – the fight or flight hormones -will be at peak in your system and the joyfulness and fulfillment will make you feel over the moon. From here, your body begins to settle and hormones levels such as estrogen and progesterone, will start to drop allowing your body to start its journey back to the pre-baby stage.

How can they affect your fitness and wellbeing journey?

For the next three to six months, you may find yourself relying on adrenaline to survive the lack of sleep while you are getting your baby settled into a routine. You may find it hard to find time for yourself or have the energy to go out for a walk or meet your friends. With time, the pressure of motherhood together with the dramatic drop of estrogen, progesterone and serotonin, may cause symptoms like:

●mood swings and anxiety
●postpartum depression
●chronic fatigue
●low libid
●cysts / fibroids
●weight gain

It will take some time for your body to recover and return to your pre-baby body shape and embracing your new You is part of the recovery process.Exercise helps to promote a natural hormonal balance and is a great mood remedy.Being fit and healthy not only helps to restore your physical health, but also helps with releasing stress and coping better with the highs and lows of motherhood.Postpartum fitness will make you feel more positive and confident. You can start your fitness journey easy and listen to how your body feels. Start by going out for walks and doing gentle stretches as well as strengthening your pelvic floor muscles.

“Often it is not how much you do but how well you do, so there is no need tospend hours exercising.”

If you are not sure what exactly is right for you, you can find support from a specialised healthcare professional such as a Post-Natal Personal Trainer or a physical therapist. They are trained to provide you with a thorough physical exam and advise on the type of exercises that are safe and suitable for you.

Written by Aline – Pre & Post Natal Expert at Motivate PT

Reps Level 3 Qualified Personal Trainer

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