Hormonal Changes in pregnancy

During your pregnancy almost all physiological and psychological changes in your body are a results of the hormones produced by your body.

The predominant hormones of pregnancy are: 

  • Beta Chorionic Gonadotropin or β-HCG as you will see it in your laboratory tests
  • Progesterone
  • Oestrogen
  • Relaxin

Then during childbirth and then we have the increase of hormones : 

  • Oxytocin
  • Prolactin

While adrenaline and cortisol are considered inhibitory hormones during childbirth.

Now let’s analyse a bit more..

Hormonal changes are necessary for the smooth transition and continuation of the pregnancy.

At the beginning of pregnancy and until the placenta is created, these hormones are produced by the so-called corpus luteum in the mother’s ovaries. The corpus luteum is a transient mechanism of the female body that secretes hormones, mainly progesterone, in the first weeks of pregnancy until the placenta is embedded into the endometrium wall. 

Progesterone and Beta chorionic gonadotropin

Progesterone protects pregnancy and helps it establish. At the site where the fertilised egg is embedded into the endometrium wall, the so-called “trophoblast” is created. This initiates the secretion of beta-chorionic gonadotropin, the hormone of pregnancy. This hormone helps to increase the endometrial wall to facilitate the growth of the fertilised egg.

Then the trophoblast turns into the placenta, and the placenta assumes the secretion of gestational hormones.

Progesterone is also responsible for an increase in the size of the breasts, a moderate increase in the woman’s temperature and the associated constipation in pregnancy.


Estrogens aid the development of the fetus, the enlargement of the uterus and placenta as well as the creation and development of milk ducts in the breasts in preparation of the body for lactation.

Estrogens are also responsible for increased blood volume during pregnancy which will be discussed in a separate chapter. Along with estrogens, progesterone is also responsible for any changes in liver and kidney function, sugar, fat, and protein levels.


The so-called “love hormone” is the dominant hormone during childbirth. It is this hormone that causes the “waves” or so-called contractions during childbirth and postnatally during breastfeeding. It is responsible for the dilation and opening of the cervix and for the contraction of the uterus during and after childbirth.

Fun fact: It is the hormone that is secreted during orgasm and for this reason many times after and during orgasm the uterus contracts

This hormone, in addition to contraction, is also of great importance emotionally as it partially activates the feelings of love towards our newborn when it is born.


Prolactin is the hormone responsible for lactation. It is secreted by the pituitary gland and in addition to helping the production and secretion of breast milk it also has stress relieving properties.


This hormone is of particular interest in pregnancy, since, together with progesterone, they cause a relaxation of the soft tissues of the joints, often causing pain and discomfort.  This in turn can also cause a relative imbalance of the core in pregnancy, while already the center of gravity changes due to the increased weight in the abdomen. But not everything is bad.

Relaxin is also the hormone, along with prostaglandins and progesterone that helps soften the cervix during labour.

Adrenaline and cortisol

These hormones are not beneficial to the body during pregnancy and childbirth. They are caused by situations of fear and anxiety either during childbirth or pregnancy in general. 

Research in infant psychology, in the new branch of fetal psychology, has linked increased stress during pregnancy and the subsequent increase of cortisol with anxiety disorders and attention deficit disorders in older children.

In addition, the production of adrenaline during childbirth has an inhibitory effect on oxytocin and can interfere with the course of childbirth. 

Please join our pregnancy education classes here at Hera Family Care if you want more information like this!

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