The Hormones That Promote Pregnancy & Their Purpose


Some days back, I was talking with a few friends and it was about how pregnancy affects women in different ways. One of my friends mentioned her sister-in-law (her husband’s younger brother’s wife), who is pregnant and has become like hot coal, with a temper on a very short leash.

She picks quarrels at the slightest opportunity and the sharpest edge of her tongue has been on duty ever since the day she started showing. We all said, “God forbid that kind of pregnancy that will be making me to fight.”

But my sisters, we cannot understand exactly what is going on in her body and how she is feeling. We only see her reaction and make our conclusions. I should add that she was not such a troublesome person before she got pregnant, although she’s got a smart mouth on her, which pregnancy has now enhanced.

Pregnancy affects us all in different ways. For some pregnant moms, they are unable to eat before conceiving, yet they find that, immediately they conceive, they would eat the whole house, if care is not taken. They are now always hungry and nothing is forbidden.

All of these actions and reactions boil down to the play of hormones in the body. This article will feature hormones which make pregnancies not only possible but also sustain them, in addition to doing all sorts of things to the pregnant woman’s mind and body.

1. Human Chorionic Gonadotropin (HCG)

HCG is one of the earliest hormones to show up in pregnancy. Early pregnancy tests also look out for this hormone in urine (which is its exit point from the body,) as it is wont to be on the increase during the early stages of a pregnancy. It is the key hormone that’s present during early pregnancy, whose basic job is to tell a woman’s body, “There is life growing inside of you.” and that her body needs to accommodate it.

HCG also tells the ovaries to stop further release of matured eggs monthly. HCG levels rise eight days after ovulation, peak at 60 to 90 days and then lower slightly, leveling off for the remainder of the pregnancy. Typically, during the first 10 weeks of your pregnancy HCG levels double every two days.

The down side: Although not confirmed, there are doctors who believe that increased HCG in the body is the cause of ‘morning’ sickness in pregnant women, which could actually even be in the afternoon, evening or even at night. It was discovered that women with higher levels of HCG often experience more nausea and vomiting.
Many researchers say it is no coincidence that morning sickness usually subsides around the same time that hCG levels start to decrease, which is right about when the second trimester starts.

2. Progesterone

This hormone is present before conception takes place, preparing the uterus for the arrival of the fertilised egg(s). During pregnancy, this hormone ensures that the uterus muscles remain relaxed and assists the immune system in tolerating ‘foreign DNA’ of your developing foetus.

Aside from relaxing the muscles of the uterus and ensuring it does not stifle the new life growing, it also leads to the relaxation of the blood vessels throughout the body, prompting lower than normal blood pressure and occasionally dizziness, that’s almost a normal part of any pregnancy, not forgetting heartburn, reflux, belching, nausea, vomiting, gas, and constipation.

Progesterone can also increase hair growth — you may notice both wanted hair, in the form of a fuller head of hair, and unwanted hair on your breasts and lower abdomen. It’s all part of the package.

3. Estrogen

I like to think of Estrogen as the baby former, as this pregnancy hormone plays a key role in the development of the foetus. The formation of several body organs and systems in the embryo is triggered into development by estrogen. Once you’ve reached the end of the first trimester, your body has higher levels of circulating estrogen, and then the levels plateau.

The role of estrogen is super-important: It helps to stimulate hormone production in the fetus’s adrenal gland, a necessary gland in a developing foetus, it stimulates the growth of the adrenal gland itself, and it enhances the mother’s uterus, enabling it to respond to oxytocin (another pregnancy hormone).

The downside, or should I say, the upside, as it is two ways, is that elevated estrogen levels may also prompt spider veins, nausea, increased appetite, and skin changes including changes in skin’s colourations. The upside is, you could be lucky enough to experience the “pregnancy glow,’ which is another offshoot of the levels of estrogen in the body.

4. Oxytocin


The hormone known as oxytocin is responsible for stretching the cervix and stimulating the nipples to start production of milk. Aside from being called the ‘feel good’ hormone, it is also called, the ‘hormone of love’ as its production is associated with lovemaking, fertility, and contractions during childbirth, together with the release of milk for a baby.

Receptor cells that make it possible for your body to respond to oxytocin tend to increase throughout pregnancy and are at their peak during childbirth. This hormone stimulates powerful contractions, which goes a long way in terms of effacing and dilating the cervix, moving the baby down the birth canal, expelling the placenta and curbing bleeding at the site of the detached placenta.

While it is widely believed that oxytocin induces labour (in fact, the drug used to induce labour, Pitocin, is the synthetic form of oxytocin), according to doctors, the levels of this hormone in the body do not rise as labour begins, just that the uterus becomes extra sensitive to it, as the pregnancy nears its end.

5. Prolactin

This is the milk-producing hormone. It increases 10 to 20 times during pregnancy and has a tranquilizing effect. Prolactin prepares the breast tissues for lactation and the release of milk.

6. Relaxin

When a pregnancy nears its end, this hormone starts to send signal to the membranes surrounding the foetus, that it’s time to give up their cargo. To the cervix, vagina and ligaments at front of the pelvis, there is a softening process going on, so that the baby may move into the birth canal.

In all, relaxin helps to maintain a healthy pregnancy and ensure that a vaginal delivery is possible. During pregnancy women have 10 times the normal amount of this pregnancy hormone in their bodies.

The down side: You may feel that your ligaments are ‘looser,’ including your shoulders, knees, hips, and ankles, which can result in aches, pain, inflammation, and even clumsy tendencies.

When all of these hormones are in your body at the same time, and in increased levels, it can become very hard to act the way people used to know you. So, don’t beat yourself up, if you find that your temper seems to be short these days, that you cry at the drop of a hat, or even just doze wherever and whenever. It’s all part of growing that baby.

Enjoy it.



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