Are headaches in early pregnancy a sign of miscarriage?

I was just reading this news on the Daily Mail regarding headaches during pregnancy. The article says that though headaches are common during pregnancy, a  small percentage are caused by life-threatening neurological conditions that include blood clots and a pressure build-up within the skull.

While there is no need to feel overtly panicky about headaches, women should be aware that if they suffer from continuous headaches during pregnancy or migraines that are very different their normal type, they should discuss it with their doctor.

After reading that bit of news, I was reminded of my own devastating miscarriage some two years ago.

My pregnancy was progressing fine and except for a bit of spotting in the 6th week which stopped within 3-4 days, everything seemed smooth sailing.

I didn't experience the usual symptoms of vomiting, nausea, increased urination or sore breasts in the initial weeks. Beginning from the 8th week or so, I would get a bad taste in the mouth, began to have a dislike for certain foods and had an heightened sense of smell along with sore breasts.

The 10 week ultrasound scan showed the baby growing normally. So far, so good.

In the twelfth week, I started getting headaches. The headaches persisted for 3-4 days; I even called the doctor who just brushed it off as a normal pregnancy symptom and asked me to apply pain balm or take a paracetamol like crocin if it was worse.

However, I didn't take any medication and the headaches stopped on their own. I really can't blame the doctor for this as according to the American Pregnancy website, headaches during the first trimester is believed to be caused by the surge of hormones along with an increase in the blood volume circulating throughout your body.

These headaches may be further aggravated by stress, poor posture or changes in your vision.

At 13 weeks I was called for another medical checkup. My meds were changed as it was the beginning of my 2nd trimester and the doctor said that everything was fine. 

After that, again I started getting headaches; I had never experienced such persistent headaches for days together in my life. I should have called the doctor but it didn't occur to me.

I would also get terrible nightmares some nights and I was getting a feeling that all was not well. Something seemed amiss somewhere.

My pregnancy symptoms seemed to disappear and I thought it was normal because anyway most women report that their symptoms disappear after the first trimester. But even then I had an uneasy feeling.

After the 17th week, I was supposed to have another complete obstetric scan. I just hoped that everything would be alright. But 4 days before the scheduled scan, I started bleeding without any cramps.

The ultrasound revealed that the fetus had no heartbeat and had stopped growing at 15 weeks. And thus I lost my baby. After this devastating miscarriage, I didn't get such terrible headaches ever again but I went through a phase of depression that lasted for several months.

Now my question is -  are terrible headaches during the first trimester of pregnancy an indication that everything's not right with the pregnancy? What about recurring nightmares accompanied by an uneasy feeling? Do they also foretell that the pregnancy is not viable?  At least in my case it was so!

Did any of you suffer from migraines / headaches or had nightmares before a missed abortion or miscarriage? What causes the fetal growth to stop abruptly? Is it low progesterone?  Is it due to chromosomal abnormalities? Or is it because the conditions in the uterus is not favorable for fetal growth? 

Do share your experiences and thoughts in the comments.

Conributed by Smitha